Conveying device and position detection device for a slide

Abstract

The conveying device is provided with a slider (30), a conveying section (1, 2), a magnetic scale (34) for detecting the position of the slider, and a magnetic sensor (12) for detecting the magnetism of the magnetic scale. The magnetic scale includes a plurality of magnetic tracks (34a-34f) arranged in parallel, and the magnetization start position and the magnetization end position of a part of the magnetic tracks (34a) are arranged offset to the opposite side of the end of the magnetic track compared with the magnetization start position and the magnetization end position of the other magnetic tracks (34b-34f).

Description

Technical Field

[0001] This invention relates to a conveying device and a position detection device for a sliding component, and particularly to a conveying device having a sliding component and a position detection device for the conveyed sliding component. Background Technology

[0002] Previously, position detection devices for conveyed sliding parts were known. Such position detection is disclosed, for example, in Japanese Patent Application Publication No. 2019-160991.

[0003] Japanese Patent Application Publication No. 2019-160991 discloses a position detection device (position detection device for a slider), which includes: a magnetic scale disposed on a slider that moves in a predetermined direction and extends in a predetermined direction for detecting the position of the slider; and a magnetic sensor disposed on a conveying section that moves the slider in the predetermined direction for detecting the magnetism of the magnetic scale. In the position detection device disclosed in Japanese Patent Application Publication No. 2019-160991, the magnetic scale includes a plurality of (6) magnetic tracks arranged in parallel, and each of the plurality of magnetic tracks is magnetized with magnetic information in a predetermined direction by a magnetizing device.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2019-160991 Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] While not described in Japanese Patent Application Publication No. 2019-160991, it is known that magnetic information is unstable (magnetically disordered and unstable) near both ends of the magnetic track of a magnetic ruler, resulting in low accuracy of the magnetic information near the ends of the magnetic ruler. Therefore, in the existing position detection device disclosed in Japanese Patent Application Publication No. 2019-160991, the low accuracy of the magnetic information near the ends of the magnetic ruler sometimes prevents high-precision detection of the slider's position. Therefore, a conveying device and a slider position detection device capable of high-precision detection of the slider's position are desired.

[0009] The present invention was made to solve the above-mentioned problems. One object of the present invention is to provide a conveying device and a sliding member position detection device that can detect the position of a sliding member with high precision.

[0010] Technical solutions for solving the problem

[0011] To achieve the above objectives, the conveying device of the first aspect of the present invention includes: a slider; a conveying section for moving the slider in a predetermined direction; a magnetic scale disposed on the slider in a manner extending in the predetermined direction for detecting the position of the slider; and a magnetic sensor disposed on the conveying section for detecting the magnetism of the magnetic scale, the magnetic scale including a plurality of magnetic tracks arranged parallel to a direction orthogonal to the predetermined direction, wherein the magnetization start position and magnetization end position of a portion of the magnetic tracks are offset to the opposite side of the end of the magnetic track compared to the magnetization start position and magnetization end position of other magnetic tracks.

[0012] In the conveying device of the first aspect of the present invention, as described above, the magnetization start position and magnetization end position of a portion of the magnetic tracks are offset to the opposite side of the end of the magnetic track compared to the magnetization start and end positions of the other magnetic tracks. Therefore, when the magnetic sensor does not detect the magnetism of all the magnetic tracks of the magnetic scale, it can be determined that it is near the end of the magnetic scale, thus suppressing the detection of magnetic information with low accuracy (magnetic disorder or instability) near the end of the magnetic scale for slider position detection. Furthermore, when the magnetic sensor detects the magnetism of all the magnetic tracks of the magnetic scale, since the magnetic information of the other tracks is magnetically stable, the magnetic information of the other tracks can be used to determine whether the magnetic information of the portion of the tracks is at a magnetically stable position. Therefore, the timing for starting slider position detection can be determined with high precision. As a result, the position of the slider can be detected with high precision.

[0013] In the conveying device of the first aspect described above, preferably, each of the plurality of magnetic tracks includes a magnetically stable region where the magnetic information is magnetically stable and a magnetically unstable region disposed on the outer sides of both ends of the magnetically stable region where the magnetic information is magnetically unstable. The magnetization start position and magnetization end position of a portion of the magnetic tracks are offset to the opposite side of the track's end compared to the magnetically unstable regions of the other magnetic tracks. If configured in this way, when the entire magnetism of the plurality of magnetic tracks, including the portion of the magnetic track offset to the opposite side of the track's end, is detected, since the other magnetic tracks are magnetically stable regions, based on the detection of the entire plurality of magnetic tracks, magnetic information with high accuracy can be detected from the other magnetic tracks. Therefore, using the stable magnetic information of the other magnetic tracks, it is possible to determine with high precision whether the magnetic information of a portion of the magnetic tracks is at a magnetically stable position.

[0014] In this case, preferably, the multiple magnetic tracks are configured such that the magnetism changes periodically, and the magnetization start and end positions of a portion of the magnetic tracks are offset from the magnetization start and end positions of the other magnetic tracks by more than one cycle towards the end of the track. If configured in this way, the magnetic information is magnetically stable at positions offset from the magnetization start or end towards the end of the track by more than one cycle. Therefore, when the entire magnetism of the multiple magnetic tracks, including the portion of the track offset towards the end of the track, is detected, the other magnetic tracks can be reliably identified as magnetically stable regions.

[0015] In the conveying device of the first aspect described above, preferably, a plurality of magnetic sensors are arranged along a predetermined direction, and the distance from the start position to the end position of magnetization of a portion of the magnetic tracks is greater than the distance between adjacent magnetic sensors. With this configuration, the magnetism of all the magnetic tracks can be detected by any one of the adjacent magnetic sensors, thus enabling high-precision detection of the slider at all positions when the slider moves across multiple magnetic sensors.

[0016] In the conveying device of the first aspect described above, preferably, the magnetization start position and magnetization end position of one of the multiple magnetic tracks are offset towards the opposite side of the end of the track compared to the magnetization start positions and magnetization end positions of the other multiple magnetic tracks. With this configuration, since the number of magnetic tracks with their magnetization start and end positions offset towards the opposite side of the track end can be minimized, the number of other multiple magnetic tracks with stable magnetic information at positions close to the end of the magnetic scale can be increased.

[0017] In the conveying device of the first aspect described above, preferably, the magnetic scale includes: an identification magnetic track having identification information for distinguishing multiple sliders; and a position magnetic track for determining the position of the sliders, wherein a portion of the magnetic track offset from the end of the magnetic track to the opposite side of the magnetization start position and magnetization end position is included in the identification magnetic track. If configured in this way, when the magnetic sensor detects the magnetism of all the magnetic tracks of the magnetic scale, since the magnetic information of the position magnetic track used to determine the position of the sliders is magnetically stable, it is possible to use the stable magnetic information of the position magnetic track to determine with high precision whether the magnetic information of a portion of the magnetic track is at a magnetically stable position.

[0018] In the conveying device of the first aspect described above, preferably, the magnetic scale includes: a first magnetic track that periodically and repeatedly records predetermined magnetic information; and a second magnetic track that records periodic information of the first magnetic track, wherein the magnetization start position and magnetization end position of the second magnetic track are offset to the opposite side of the end of the magnetic track compared to the magnetization start position and magnetization end position of the first magnetic track. With this configuration, the magnetic information of the first magnetic track, which requires higher information accuracy than the second magnetic track for high-precision detection of the slider's position, is magnetically stable at a position close to the end of the magnetic scale.

[0019] In the conveying device of the first aspect described above, preferably, a control unit is further provided to obtain the position of the slider based on the detection results of magnetic sensors. Multiple magnetic sensors are arranged along a predetermined direction. The control unit is configured such that, when the position of the slider is obtained by detecting the magnetism of the magnetic scale using one magnetic sensor, and when the magnetism of a magnetic stable region where the magnetic information of all magnetic tracks in the multiple magnetic tracks of the magnetic scale is magnetically stable is detected by another magnetic sensor adjacent to one magnetic sensor, control to obtain the position of the slider based on the detection results of the other magnetic sensor is initiated. With this configuration, it is possible to switch from one magnetic sensor to the other when the magnetic information of the magnetic track detected by the other magnetic sensor is magnetically stable.

[0020] In this case, preferably, the control unit is configured to determine whether the magnetic information of the magnetic track of the magnetic ruler is in a magnetically stable region based on whether the magnetic sensor detects magnetism. If configured in this way, it is possible to determine whether magnetism is detected even when the magnetic information is unstable, thus enabling high-precision determination of whether the magnetic track of the magnetic ruler is in a magnetically stable region.

[0021] In a structure that determines whether a track of a magnetic ruler is a magnetically stable region based on whether the aforementioned magnetism is detected, preferably, the control unit is configured to determine that, when the magnetism of all tracks in a plurality of tracks is detected, the other tracks in the plurality of tracks are magnetically stable regions. If configured in this way, it is possible to determine with high precision whether other tracks in the plurality of tracks that are longer than some of the tracks are magnetically stable regions.

[0022] In a structure that determines whether a track of a magnetic ruler is in a magnetically stable region based on whether the aforementioned magnetism is detected, the control unit is preferably configured to determine whether a portion of the multiple tracks is in a magnetically stable region based on the magnetic information of the other tracks, when the other tracks are magnetically stable regions. If configured in this way, it is possible to determine with high accuracy whether a portion of the tracks shorter than the other tracks is in a magnetically stable region based on the magnetic information of the other tracks that have already become magnetically stable regions.

[0023] To achieve the above objective, the slider position detection device of the second aspect of the present invention includes: a magnetic scale, which is provided on a slider that moves in a predetermined direction and extends in a predetermined direction, for detecting the position of the slider; and a magnetic sensor, which is provided on a conveying section that moves the slider in the predetermined direction, for detecting the magnetism of the magnetic scale. The magnetic scale includes a plurality of magnetic tracks arranged parallel to a direction orthogonal to the predetermined direction. The magnetization start position and magnetization end position of a portion of the magnetic tracks are offset to the opposite side of the end of the magnetic track compared to the magnetization start position and magnetization end position of other magnetic tracks.

[0024] In the slider position detection apparatus of the second aspect of the present invention, as described above, the magnetization start position and magnetization end position of a portion of the magnetic tracks are offset to the opposite side of the end of the magnetic track compared to the magnetization start position and magnetization end position of the other magnetic tracks. Therefore, when the magnetic sensor does not detect the magnetism of all the magnetic tracks of the magnetic scale, it can be determined that it is near the end of the magnetic scale, thus suppressing the detection of low-precision (unstable) magnetic information near the end of the magnetic scale for slider position detection. Furthermore, when the magnetic sensor detects the magnetism of all the magnetic tracks of the magnetic scale, since the magnetic information of the other tracks is magnetically stable, the magnetic information of the other tracks can be used to determine whether the magnetic information of the portion of the tracks is at a magnetically stable position. Therefore, the timing for starting slider position detection can be determined with high precision. As a result, a slider position detection apparatus capable of detecting the position of a slider with high precision can be provided.

[0025] Invention Effects

[0026] According to the present invention, as described above, the position of the slider can be detected with high precision. Attached Figure Description

[0027] Figure 1 This is a top view of a conveying device according to one embodiment of the present invention.

[0028] Figure 2 This is a cross-sectional view of the conveying section and sliding member of a conveying device according to one embodiment of the present invention.

[0029] Figure 3 This is a diagram showing a magnetic scale of a conveying device according to one embodiment of the present invention.

[0030] Figure 4 This is a diagram showing the vicinity of the end of the magnetic scale of a conveying device according to one embodiment of the present invention.

[0031] Figure 5 This is a diagram showing the relationship between the magnetic scale and multiple magnetic sensors of a conveying device according to one embodiment of the present invention.

[0032] Figure 6 This is a diagram illustrating an example of the magnetic pattern of the magnetic scale of a conveying device according to one embodiment of the present invention.

[0033] Figure 7 This is a flowchart illustrating the position detection start process of the control unit of a conveying device according to one embodiment of the present invention. Detailed Implementation

[0034] Hereinafter, embodiments embodying the present invention will be described with reference to the accompanying drawings.

[0035] Reference Figures 1 to 7 The structure of a conveying device 100 according to one embodiment of the present invention will be described.

[0036] (Structure of the conveying device)

[0037] The conveying device 100 of this embodiment is configured to convey a transport object placed on the sliding member 30 along the conveying sections 1 and 2. Furthermore, the transport object conveyed by the conveying device 100 is operated at multiple conveying positions. The transport object is operated by a robot or an operator.

[0038] like Figure 1 As shown, the conveying device 100 includes a conveying section 1, a conveying section 2, a transfer conveying section 3, a transfer conveying section 4, and a sliding member 30. Additionally, the conveying device 100 includes a control section 40.

[0039] Conveying section 1 includes multiple conveying modules 10. Conveying section 2 includes multiple conveying modules 10. The multiple conveying modules 10 are connected in series to form a conveying path for the sliding member 30. The sliding member 30 is conveyed along the X direction on conveying sections 1 and 2, and conveyed along the Y direction from conveying section 1 (2) to conveying section 2 (1) via switching conveying sections 3 and 4. That is, the sliding member 30 is conveyed and used cyclically in the order of conveying section 1, switching conveying section 3, conveying section 2, and switching conveying section 4.

[0040] like Figure 2 As shown, the conveying module 10 includes a linear motor stator 11, a magnetic sensor 12, a guide rail 13, and a cover 14.

[0041] like Figure 1 As shown, the transfer and conveying units 3 and 4 include a conveying mechanism 20 for conveying the sliding member 30 along the X direction and a moving mechanism for moving the conveying mechanism 20 along the Y direction. The conveying mechanism 20 has a linear motor stator 11 and a magnetic sensor 12. The moving mechanism has a guide rail and a ball screw mechanism.

[0042] like Figure 2As shown, the slider 30 includes a slider body 31, a linear motor mover 32, a guide block 33, and a magnetic scale 34. Multiple sliders 30 are provided. Furthermore, the multiple sliders 30 are configured to move independently on the conveying units 1 and 2, and the transfer conveying units 3 and 4.

[0043] Conveying units 1 and 2 are configured to move the slider 30 along a predetermined direction (X direction). Furthermore, conveying units 1 and 2 are arranged substantially parallel to each other. Conveying unit 1 conveys the slider 30 along the X2 direction, and conveying unit 2 conveys the slider 30 along the X1 direction. Conveying units 1 and 2 are fixedly mounted on a frame. That is, the linear motor stator 11 and guide rail 13 of conveying units 1 and 2 are fixedly mounted.

[0044] The transfer conveyor 3 is positioned adjacent to the conveyor 1 and 2 in the X2 direction. The transfer conveyor 4 is positioned adjacent to the conveyor 1 and 2 in the X1 direction.

[0045] The linear motor stator 11 includes an electromagnet, and the sliding member 30 is moved by supplying driving power (current) to the electromagnet. The linear motor stator 11 is arranged along the conveying direction (X direction). Additionally, as... Figure 2 As shown, the electromagnets of the linear motor stator 11 are configured to extend along the Y direction.

[0046] A magnetic sensor 12 is provided on the conveying units 1 and 2. Furthermore, the magnetic sensor 12 is configured to detect the magnetism of the magnetic scale 34. Specifically, the magnetic sensor 12 is positioned facing the magnetic scale 34 provided on the slider 30 in the Y direction. The magnetic sensor 12 is configured to detect the magnetism of the magnetic scale 34, thereby detecting the position of the slider 30. The position of the slider 30 detected by the magnetic sensor 12 is used for feedback control of the movement of the slider 30.

[0047] In addition, such as Figure 5 As shown, multiple magnetic sensors 12 are arranged at intervals along the transport direction (X direction). Furthermore, the magnetic sensors 12 are configured to send a signal corresponding to the detected magnetism to the control unit 40.

[0048] The guide rails 13 are configured to extend along the conveying direction (X direction) of the slider 30. A pair of guide rails 13 are arranged parallel to each other along the Y direction. The sliders 30 are variably aligned between adjacent conveying modules 10 in the X direction. The guide blocks 33 of the sliders 30 are engaged with the guide rails 13 in a manner that allows them to move along the X direction.

[0049] The cover 14 is provided to cover the top of the linear motor stator 11, the magnetic sensor 12, and the guide rail 13. That is, the cover 14 is configured so that the top of the linear motor stator 11, the magnetic sensor 12, and the guide rail 13 will not be exposed even when the slider 30 is not present.

[0050] The sliding body 31 is configured to hold the object to be conveyed. Furthermore, viewed from the conveying direction (X direction), the sliding body 31 is arranged in a manner that surrounds the conveying sections 1 and 2 as a cover 14. A linear motor mover 32, a guide block 33, and a magnetic scale 34 are mounted on the sliding body 31.

[0051] The linear motor mover 32 is configured to clamp the linear motor stator 11 in the Y direction. The linear motor mover 32 includes a plurality of permanent magnets arranged along the transport direction (X direction).

[0052] The guide block 33 is configured to move along the guide rail 13. The guide block 33 has a plurality of balls that move and circulate in the direction of movement.

[0053] The magnetic scale 34 is provided on the slider 30 in a manner extending along a predetermined direction (X direction). Furthermore, the magnetic scale 34 is provided for detecting the position (conveyor position) of the slider 30. Additionally, the magnetic scale 34 is magnetized into a predetermined pattern along the conveyor direction (X direction). Furthermore, as... Figure 5 As shown, the position detection device 200 includes a magnetic ruler 34 and a magnetic sensor 12 for detecting the magnetism of the magnetic ruler 34. Furthermore, the position detection device 200 is an example of a "position detection device for a sliding member" in the technical solution.

[0054] The magnetic scale 34 is formed by magnetizing a scale material in a predetermined pattern. The scale material is formed of a magnetic material (e.g., a metal magnet, a plastic magnet, or a rubber magnet). The scale material is formed entirely of the same material and quality, and the presence or absence of a magnetic field, the amplitude of the period, and the strength of the magnetic field are managed by magnetization. Furthermore, the magnetization of the scale material is performed while it is assembled on a back plate, which is a rigid body.

[0055] Here, as Figure 3 As shown, in this embodiment, the magnetic ruler 34 includes a plurality of magnetic tracks 34a, 34b, 34c, 34d, 34e, and 34f arranged parallel to a direction orthogonal to a predetermined direction (X direction) and a direction (Z direction). Furthermore, the magnetization start position P2 and magnetization end position P3 of a portion of the magnetic tracks 34a to 34f are offset towards the opposite side of the end of the track (offset towards the center of the track) compared to the magnetization start position P1 and magnetization end position P4 of the other magnetic tracks 34b to 34f. That is, the magnetization start position P2 is offset towards the X2 direction compared to the magnetization start position P1. Similarly, the magnetization end position P3 is offset towards the X1 direction compared to the magnetization end position P4.

[0056] Specifically, such as Figure 4As shown, the multiple magnetic tracks 34a to 34f each include a magnetically stable region 341 where the magnetic information is stable and a magnetically unstable region 342 located on the outer sides of both ends of the magnetically stable region 341 where the magnetic information is magnetically unstable. That is, magnetic disturbances are generated near the magnetized ends (magnetically unstable regions 342). Therefore, the phase difference between the multiple magnetic tracks is not constant.

[0057] Furthermore, the multiple magnetic tracks 34a to 34f are configured such that their magnetic properties change periodically. Additionally, the magnetic ruler 34 includes identification tracks (tracks 34a to 34c) for distinguishing the multiple sliders 30 and position tracks (34d to 34f) for determining the position of the sliders 30. That is, by detecting the magnetic information of tracks 34a to 34c, it is possible to determine which of the multiple sliders 30 it is. Furthermore, by acquiring the magnetic information of tracks 34d to 34f, it is possible to determine the location of the determined slider 30 relative to the magnetic sensor 12.

[0058] like Figure 6 As shown, the identification track is configured such that, based on the main track 34b, the track 34c of the vernier (vernier scale) and the segmented tracks 34a have magnetic periods that represent a certain phase difference with different periods (spacing).

[0059] The magnetic scale 34 includes tracks 34b and 34c that periodically and repeatedly record predetermined magnetic information, and track 34a that records periodic information of tracks 34b and 34c. That is, the main track 34b and the vernier track 34c periodically and repeatedly record predetermined magnetic information. Additionally, the segmented track 34a records information determining which period tracks 34b and 34c are in.

[0060] In addition, in this embodiment, such as Figure 3 and Figure 4 As shown, the magnetization start position P2 and magnetization end position P3 of a portion of the magnetic tracks 34a to 34f are offset to the opposite side of the end of the track compared to the magnetically unstable region 342 of the other magnetic tracks 34b to 34f. Specifically, the magnetically unstable region 342 has a distance D1 from the end. In addition, the inner side of the magnetically unstable region 342 is called the magnetically stable region 341. The magnetization start position P2 and magnetization end position P3 of the track 34a are positioned at a distance D2 (> D1) inward than the magnetization start position P1 and magnetization end position P4 of the tracks 34b to 34f.

[0061] Furthermore, the magnetic scale 34, for example, is configured with the position (based on the coordinates of the magnetic tracks 34d to 34f (position tracks)) for identifying and determining the position of the slider 30, based on a pre-conceived maximum detection delay of 1 / 4 cycle. This allows for the suppression of timing deviations in determining each scale.

[0062] Furthermore, the magnetization start position P2 and magnetization end position P3 of a portion of the magnetic tracks 34a to 34f are offset from the magnetization start position P1 and magnetization end position P4 of the other magnetic tracks 34b to 34f by more than one cycle to the opposite side of the end of the track. That is, the distance D2 between the magnetization start positions P1 and P2 (and magnetization end positions P3 and P4) is larger than one cycle of the longest cycle in the magnetic tracks 34b to 34f.

[0063] Here, regardless of the material state of the magnetic scale 34, during continuous magnetization, the portion of the period at the end, which is one wavelength (one cycle), is placed in a different environment than the portions of other cycles (the inner cycles). That is, in the inner cycles, the predetermined magnetic characteristics are exhibited based on the magnetic influence of the adjacent cycles. However, in the one cycle at the end, since there is no magnetic cycle on the outer side, the balance is different from that of the inner cycles. Therefore, even when the same magnetization setting is performed, the magnetic field distribution becomes subtly different. Therefore, by aligning the six magnetic tracks 34a to 34f, and making the trigger position for position detection one wavelength (one cycle) or more inward from the end, which is the magnetization start position P1 (magnetization end position P4), the magnetic characteristics of the other magnetic tracks 34b to 34f can be stabilized.

[0064] In addition, such as Figure 5 As shown, the distance from the magnetization start position P2 to the magnetization end position P3 of a portion of the multiple magnetic tracks 34a to 34f is greater than the distance between adjacent magnetic sensors 12. Therefore, while any one of the adjacent magnetic sensors 12 is in a controlled state, the magnetism of all magnetic tracks 34a to 34f can be detected, and the control unit 40 can begin control. As a result, when the slider 30 moves across multiple magnetic sensors 12, the position can be detected with high precision at all positions of the slider 30. Furthermore, the slider 30 will not fall into an uncontrolled state. That is, when the slider 30 moves across multiple magnetic sensors 12, in a state of feedback control based on the detection results of the previous magnetic sensor 12, the next magnetic sensor 12 reaches the magnetically stable region 341 of the magnetic track 34a, thereby enabling the handover of control between multiple magnetic sensors 12 within the magnetically stable region 341 while in a state of feedback control.

[0065] Furthermore, the magnetization start position P2 and magnetization end position P3 of one of the magnetic tracks 34a to 34f are offset to the opposite side of the end of the track compared to the magnetization start position P1 and magnetization end position P4 of the other magnetic tracks 34b to 34f. That is, only one magnetic track 34a is shortened.

[0066] The control unit 40 is configured to control various parts of the conveying device 100. The control unit 40 controls the power supplied to the linear motor stator 11 and controls the movement of the sliding member 30. Additionally, the control unit 40 controls the drive of the moving mechanism 21 of the switching conveying units 3 and 4 and controls the movement of the conveying mechanism 20. The control unit 40 includes a CPU (central processing unit), memory, etc.

[0067] Here, the control unit 40 is configured to obtain the position of the slider 30 based on the detection result of the magnetic sensor 12. Furthermore, the control unit 40 is configured such that, when the position of the slider 30 is obtained by detecting the magnetism of the magnetic scale using one magnetic sensor 12, and when the magnetism of the magnetic stable region 341 of all magnetic tracks 34a-34f of the magnetic scale 34 is detected by another magnetic sensor 12 adjacent to one of the magnetic sensors 12, control is initiated to obtain the position of the slider 30 based on the detection result of the other magnetic sensor 12.

[0068] Specifically, the control unit 40 is configured to determine whether it is a magnetically stable region 341 where the magnetic information of the magnetic tracks 34a to 34f of the magnetic ruler 34 is stable, based on whether the magnetic sensor 12 detects magnetism.

[0069] Furthermore, the control unit 40 is configured such that, when the magnetism of all magnetic tracks 34a to 34f is detected, the other magnetic tracks 34b to 34f among the multiple magnetic tracks 34a to 34f are determined to be magnetically stable regions 341.

[0070] Furthermore, the control unit 40 is configured to determine, based on the magnetic information of the other magnetic tracks 34b to 34f, whether a portion of the magnetic tracks 34a to 34f is a magnetically stable region 341 when the other magnetic tracks 34b to 34f are magnetically stable regions 341.

[0071] (Location detection processing begins)

[0072] Reference Figure 7 The position detection start process during the switching of the magnetic sensor 12 by the control unit 40 of the conveying device 100 will be described. Furthermore, this process is the process of switching (changing) the magnetic sensor 12 used for identifying the magnetism of the slider 30 and obtaining its position when the slider 30 moves and the magnetic ruler 34 is arranged across two adjacent magnetic sensors 12.

[0073] exist Figure 7 In step S1, the control unit 40 determines whether the magnetic sensor 12 at the destination of the conversion detects the magnetism of the five magnetic tracks 34b to 34f. The determination in step S1 is repeated until the magnetism of the five magnetic tracks 34b to 34f is detected.

[0074] When the magnetism of five tracks 34b to 34f is detected, in step S2, the control unit 40 determines whether the magnetism of all tracks 34a to 34f has been detected. That is, in addition to the tracks 34b to 34f currently being detected, it also determines whether the magnetism of track 34a, which is the segment used to identify the tracks, has been detected. The determination in step S2 is repeated until the magnetism of all tracks 34a to 34f has been detected.

[0075] When the magnetism of all magnetic tracks 34a to 34f is detected, in step S3, based on the position magnetic tracks (tracks 34d to 34f), it is determined whether the position of the magnetic ruler 34 (slider 30) has moved within a predetermined range. That is, based on the magnetic information of the position magnetic tracks (tracks 34d to 34f), it is determined whether the shorter magnetic track 34a has also become a magnetically stable region. The determination in step S3 is repeated until the position of the magnetic ruler 34 (slider 30) moves within the predetermined range.

[0076] When the position of the magnetic scale 34 (slider 30) moves within a predetermined range, in step S4, the magnetism of the identification magnetic tracks (tracks 34a to 34c) is detected to determine the ID of the slider 30. Then, in step S5, position detection of the slider 30 based on the converted magnetic sensor 12 begins. In this case, position detection of the slider 30 based on the original magnetic sensor 12 ends. That is, the magnetic sensor 12 used for position detection of the slider 30 is switched. After that, position detection ends and processing begins.

[0077] (Effects of this implementation method)

[0078] In this embodiment, the following effects can be achieved.

[0079] In this embodiment, as described above, the magnetization start position P2 and magnetization end position P3 of a portion of the magnetic tracks 34a to 34f are offset to the opposite side of the end of the magnetic track compared to the magnetization start position P1 and magnetization end position P4 of the other magnetic tracks 34b to 34f. Therefore, if the magnetic sensor 12 does not detect the magnetism of all the magnetic tracks 34a to 34f of the magnetic ruler 34, it can be determined that the location is near the end of the magnetic ruler 34. This prevents the detection of low-precision (unstable) magnetic information near the end of the magnetic ruler 34, which could then be used for position detection of the slider 30. Furthermore, if the magnetic sensor 12 detects the magnetism of all the magnetic tracks 34a to 34f of the magnetic ruler 34, the magnetic information of the other magnetic tracks 34b to 34f, excluding a portion of the magnetic track 34a, is magnetically stable. Therefore, the stable magnetic information of the other magnetic tracks 34b to 34f can be used to determine whether the magnetic information of a portion of the magnetic track 34a is at a magnetically stable position. Therefore, the timing for starting the position detection of the slider 30 can be determined with high precision. As a result, the position of the slider 30 can be detected with high precision.

[0080] Furthermore, in this embodiment, as described above, each of the plurality of magnetic tracks 34a to 34f includes a magnetically stable region 341 where the magnetic information is stable and a magnetically unstable region 342 disposed on the outer sides of both ends of the magnetically stable region 341 where the magnetic information is magnetically unstable. The magnetization start position P2 and magnetization end position P3 of a portion of the magnetic tracks 34a to 34f are offset towards the opposite side of the track's end compared to the magnetically unstable regions 342 of the other magnetic tracks 34b to 34f. Therefore, when the magnetism of all of the plurality of magnetic tracks 34a to 34f, including a portion of the magnetic track 34a offset towards the opposite side of the track's end, is detected, since the other magnetic tracks 34b to 34f are magnetically stable regions 341, based on the detection of all of the plurality of magnetic tracks 34a to 34f, magnetic information with high accuracy can be detected from the other magnetic tracks 34b to 34f. Therefore, it is possible to use the stable magnetic information of other magnetic tracks 34b to 34f to determine with high precision whether the magnetic information of a portion of magnetic track 34a is a stable position.

[0081] Furthermore, in this embodiment, as described above, the plurality of magnetic tracks 34a to 34f are configured such that the magnetism changes periodically, and the magnetization start position P2 and magnetization end position P3 of a portion of the magnetic tracks 34a are offset from the magnetization start position P1 and magnetization end position P4 of the other magnetic tracks 34b to 34f by more than one cycle to the opposite side of the end of the track. Therefore, at a position offset from the magnetization start or magnetization end to the opposite side of the end of the track by more than one cycle, the magnetic information is stable. Thus, when all the magnetism of the plurality of magnetic tracks 34a to 34f, including a portion of the magnetic track 34a offset to the opposite side of the end of the track, is detected, the other magnetic tracks 34b to 34f can be reliably designated as magnetically stable regions 341.

[0082] Furthermore, in this embodiment, as described above, multiple magnetic sensors 12 are arranged along a predetermined direction, such that the distance from the magnetization start position P2 to the magnetization end position P3 of a portion of the multiple magnetic tracks 34a to 34f is greater than the distance between adjacent magnetic sensors 12. Therefore, the magnetism of all the multiple magnetic tracks 34a to 34f can be detected by any one of the adjacent magnetic sensors 12, and thus, when the slider 30 moves across the multiple magnetic sensors 12, the slider 30 can be detected with high precision at all positions.

[0083] Furthermore, in this embodiment, as described above, the magnetization start position P2 and magnetization end position P3 of one of the magnetic tracks 34a to 34f are offset towards the opposite side of the end of the track compared to the magnetization start position P1 and magnetization end position P4 of the other magnetic tracks 34b to 34f. This minimizes the number of tracks with magnetization start and end positions offset towards the opposite side of the end of the track, thus increasing the number of other magnetic tracks 34b to 34f with stable magnetic information near the end of the magnetic scale 34.

[0084] Furthermore, in this embodiment, as described above, the magnetic ruler 34 includes an identification magnetic track having identification information for distinguishing multiple sliders 30 and a position magnetic track for determining the position of the sliders. A portion of the magnetic track 34a, whose magnetization start position and magnetization end position are offset to the opposite side of the end of the magnetic track, is included in the identification magnetic track. Therefore, when the magnetic sensor 12 detects the magnetism of all the multiple magnetic tracks 34a to 34f of the magnetic ruler 34, since the magnetic information of the position magnetic track determining the position of the slider 30 is magnetically stable, it is possible to use the stable magnetic information of the position magnetic track to determine with high precision whether the magnetic information of a portion of the magnetic track 34a represents a magnetically stable position.

[0085] Furthermore, in this embodiment, as described above, the magnetic scale 34 includes magnetic tracks 34b and 34c that periodically and repeatedly record predetermined magnetic information, and a magnetic track 34a that records periodic information of magnetic tracks 34b and 34c. The magnetization start position P2 and magnetization end position P3 of magnetic track 34a are offset to the opposite side of the end of the magnetic track compared to the magnetization start position P1 and magnetization end position P4 of magnetic tracks 34b and 34c. This allows the magnetic information of magnetic tracks 34b and 34c, which require higher information accuracy than magnetic track 34a for high-precision detection of the slider 30's position, to be stabilized at positions closer to the end of the magnetic scale 34.

[0086] Furthermore, in this embodiment, as described above, a control unit 40 is provided to obtain the position of the slider 30 based on the detection result of the magnetic sensor 12. This control unit 40 is configured such that, when the position of the slider 30 is obtained by detecting the magnetism of the magnetic scale using one magnetic sensor 12, and the magnetism of a magnetically stable region 341 where the magnetic information of all magnetic tracks 34a to 34f of the magnetic scale 34 is stable is detected by another magnetic sensor 12 adjacent to the one magnetic sensor 12, control is initiated to obtain the position of the slider 30 based on the detection result of the other magnetic sensor 12. Thus, it is possible to switch from one magnetic sensor 12 to the other magnetic sensor 12 when the magnetic information of the magnetic tracks 34a to 34f detected by the other magnetic sensor 12 is magnetically stable.

[0087] Furthermore, in this embodiment, as described above, the control unit 40 is configured to determine whether the magnetic information of the magnetic tracks 34a to 34f of the magnetic ruler 34 is stable within a magnetically stable region 341 based on whether the magnetic sensor 12 detects magnetism. Therefore, even in cases of unstable magnetic information, it is possible to determine whether magnetism is detected, thus enabling high-precision determination of whether the magnetic tracks 34a to 34f of the magnetic ruler 34 are magnetically stable regions 341.

[0088] Furthermore, in this embodiment, as described above, the control unit 40 is configured to determine, when the magnetism of all magnetic tracks 34a to 34f is detected, that other magnetic tracks 34b to 34f among the multiple magnetic tracks 34a to 34f are magnetically stable regions 341. Therefore, it is possible to determine with high precision that other magnetic tracks 34b to 34f that are longer than a portion of the magnetic tracks 34a are magnetically stable regions 341.

[0089] Furthermore, in this embodiment, as described above, the control unit 40 is configured to determine whether a portion of the magnetic tracks 34a among the plurality of magnetic tracks 34a to 34f is a magnetically stable region 341 based on the magnetic information of the other magnetic tracks 34b to 34f. Therefore, based on the magnetic information of the other magnetic tracks 34b to 34f that first become magnetically stable regions 341, it is possible to determine with high accuracy whether a portion of the magnetic track 34a shorter than the other magnetic tracks 34b to 34f becomes a magnetically stable region 341.

[0090] (Modified Example)

[0091] Furthermore, the embodiments disclosed herein should be considered illustrative rather than restrictive in all respects. The scope of the invention is defined not by the description of the embodiments above but by the claims, and thus includes all modifications (variations) within the meaning and scope of the claims.

[0092] For example, the above embodiment shows an example of a magnetic ruler comprising six magnetic tracks, but the present invention is not limited thereto. In the present invention, the magnetic ruler may also include more than six magnetic tracks.

[0093] Furthermore, in the above embodiment, an example was shown where the magnetization start position and magnetization end position of one of the multiple magnetic tracks of the magnetic scale are offset to the opposite side of the end of the track compared to the other tracks; however, the present invention is not limited to this. In the present invention, the magnetization start position and magnetization end position of two or more of the multiple magnetic tracks of the magnetic scale may also be offset to the opposite side of the end of the track compared to the other tracks.

[0094] Furthermore, in the above embodiment, an example is shown where three of the multiple magnetic tracks of the magnetic ruler are identification tracks for distinguishing the slider, and the remaining three magnetic tracks are position tracks for determining the position of the slider. However, the present invention is not limited to this. In the present invention, multiple identification tracks other than three, and multiple position tracks other than three, may also be provided.

[0095] Furthermore, while the above embodiments illustrate an example of a structure where the conveying unit moves the sliding member via a linear motor, the present invention is not limited to this. In the present invention, the conveying unit may also move the sliding member via a ball screw mechanism, a rotary belt mechanism, or the like.

[0096] Furthermore, the above embodiments show an example of a structure in which the magnetic ruler is vertically arranged in the vertical direction, but the present invention is not limited thereto. In the present invention, the magnetic ruler can also be arranged horizontally.

[0097] Furthermore, in the above embodiments, an example was shown where the conveying section is configured to extend in a straight line, but the present invention is not limited thereto. In the present invention, the conveying section may also be curved.

[0098] Furthermore, in the above embodiments, for ease of explanation, a process-driven approach was used, in which the control processing of the control unit is performed sequentially according to a processing flow. However, the present invention is not limited to this. In the present invention, the control processing of the control unit can also be performed using an event-driven (event-following) approach that executes processing on an event-by-event basis. In this case, it can be performed entirely as an event-driven approach, or it can be performed as a combination of event-driven and process-driven approaches.

[0099] Explanation of reference numerals in the attached figures

[0100] 1, 2 Conveying Sections

[0101] 12 Magnetic Sensors

[0102] 30 Slider

[0103] 34 Magnetic Ruler

[0104] 34a Track (Identification Track, Second Track)

[0105] Tracks 34b and 34c (identification track, first track)

[0106] Tracks 34d, 34e, and 34f (position tracks)

[0107] 40 Control Department

[0108] 100 Conveying Device

[0109] 200 Position Detection Device (Sliding Component Position Detection Device)

[0110] 341 Magnetic Stability Region

[0111] 342 Magnetic Instability Region

Claims

1. A conveying device comprising: Slider; The conveying unit moves the sliding member in a predetermined direction; A magnetic ruler is disposed on the slider in a manner that extends along the predetermined direction, for detecting the position of the slider; and A magnetic sensor, disposed in the conveying section, detects the magnetism of the magnetic ruler. The magnetic scale includes a plurality of magnetic tracks arranged parallel to a direction orthogonal to the predetermined direction. The magnetization start and end positions of a portion of the multiple magnetic tracks are offset to the opposite side of the end of the track compared to the magnetization start and end positions of the other magnetic tracks. The position detection of the slider is initiated based on the detection of the magnetism of all the magnetic tracks of the magnetic ruler by the magnetic sensor. The conveying device also includes a control unit, which determines the position of the sliding member based on the detection results of the magnetic sensor. Multiple magnetic sensors are arranged along the predetermined direction. The control unit is configured such that, when the position of the slider is obtained by detecting the magnetism of the magnetic ruler through the magnetic sensor of one of the magnetic sensors, when the magnetic information of all magnetic tracks in the plurality of magnetic tracks of the magnetic ruler is detected by the magnetic sensor of the other magnetic sensor adjacent to the magnetic sensor of the first magnetic sensor, the control unit begins to obtain the position of the slider based on the detection result of the other magnetic sensor.

2. The conveying device according to claim 1, wherein, The plurality of magnetic tracks each include: a magnetically stable region where the magnetic information is magnetically stable, and a magnetically unstable region disposed at both ends of the magnetically stable region where the magnetic information is magnetically unstable. The magnetization start and end positions of a portion of the plurality of magnetic tracks are offset to the opposite side of the end of the track compared to the magnetically unstable regions of the other tracks.

3. The conveying device according to claim 2, wherein, The multiple magnetic tracks are configured such that their magnetic properties change periodically. The magnetization start and end positions of a portion of the plurality of magnetic tracks are configured to be offset from the ends of the tracks by more than one cycle compared to the magnetization start and end positions of the other magnetic tracks.

4. The conveying device according to any one of claims 1 to 3, wherein, Multiple magnetic sensors are arranged along the predetermined direction. The distance from the start position to the end position of magnetization in one of the plurality of magnetic tracks is greater than the distance between adjacent magnetic sensors.

5. The conveying device according to any one of claims 1 to 3, wherein, The magnetization start position and magnetization end position of one of the plurality of magnetic tracks are offset to the opposite side of the end of the track compared to the magnetization start positions and magnetization end positions of the other magnetic tracks.

6. The conveying device according to any one of claims 1 to 3, wherein, The magnetic ruler includes: an identification track having identification information for distinguishing multiple sliding elements; and a position track for determining the position of the sliding elements. The portion of the magnetic track whose magnetization start position and magnetization end position are offset to the opposite side of the end of the track is included in the identification track.

7. The conveying device according to any one of claims 1 to 3, wherein, The magnetic scale includes: a first magnetic track that periodically and repeatedly records predetermined magnetic information; and a second magnetic track that records the periodic information of the first magnetic track. The magnetization start position and magnetization end position of the second magnetic track are offset to the opposite side of the end of the magnetic track compared to the magnetization start position and magnetization end position of the first magnetic track.

8. The conveying device according to claim 1, wherein, The control unit is configured to determine whether the magnetic information of the magnetic track of the magnetic ruler is magnetically stable in the magnetically stable region based on whether the magnetic sensor detects magnetism.

9. The conveying device according to claim 8, wherein, The control unit is configured to determine, when the magnetism of all the magnetic tracks in the plurality of magnetic tracks is detected, that the other magnetic tracks in the plurality of magnetic tracks are the magnetically stable region.

10. The conveying device according to claim 8 or 9, wherein, The control unit is configured to determine, based on the magnetic information of the other magnetic tracks, whether a portion of the magnetic tracks is a magnetically stable region when the other magnetic tracks are magnetically stable regions.

11. A position detection device for a sliding member, comprising: A magnetic ruler, extended in a predetermined direction, is disposed on a slider that moves in the predetermined direction, for detecting the position of the slider; and A magnetic sensor, disposed in a conveying section that moves the slider along the predetermined direction, detects the magnetism of the magnetic ruler. The magnetic scale includes a plurality of magnetic tracks arranged parallel to a direction orthogonal to the predetermined direction. The magnetization start and end positions of a portion of the multiple magnetic tracks are offset to the opposite side of the end of the track compared to the magnetization start and end positions of the other magnetic tracks. The position detection of the slider is initiated based on the detection of the magnetism of all the magnetic tracks of the magnetic ruler by the magnetic sensor. The position detection device for the slider also includes a control unit, which obtains the position of the slider based on the detection result of the magnetic sensor. Multiple magnetic sensors are arranged along the predetermined direction. The control unit is configured such that, when the position of the slider is obtained by detecting the magnetism of the magnetic ruler through the magnetic sensor of one of the magnetic sensors, when the magnetic information of all magnetic tracks in the plurality of magnetic tracks of the magnetic ruler is detected by the magnetic sensor of the other magnetic sensor adjacent to the magnetic sensor of the first magnetic sensor, the control unit begins to obtain the position of the slider based on the detection result of the other magnetic sensor.

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