Conveying device

Abstract

Provided is a conveyance device that prevents magnetic saturation and reduces the weight of the conveyance device. The conveyance device of the present invention is characterized by including: a conveyance path (65) through which a conveyance object moves; an electromagnet provided on a surface opposite to a surface on which the conveyance object moves; and a drive circuit that causes a current to flow through the electromagnet, the electromagnet having a tooth (22a, 22b) made of a magnetic body and a winding (21a, 21b) wound around a surface of the tooth (22a, 22b), a yoke (26) that supports the tooth (22a, 22b) being provided, a minimum cross-sectional area (Sy) of the yoke (26) being smaller than a minimum cross-sectional area (St) of a portion of the tooth (22a, 22b) on which the winding (21a, 21b) is provided.

Description

Technical Field

[0001] This invention relates to a conveying device. Background Technology

[0002] In a sample analysis system that analyzes biological samples (hereinafter referred to as "samples") such as blood, plasma, serum, urine, and other bodily fluids, multiple functional devices are connected to automatically process each step in order to perform the indicated analytical items for each sample. In other words, in a sample analysis system, analytical departments from multiple analytical fields, such as biochemistry and immunology, are connected by conveyor lines to perform multiple analyses in a unified manner.

[0003] The conveying methods of the conveyor line include: (1) belt conveyor; (2) using electromagnetic attraction as thrust. In recent years, in order to improve the analytical processing capabilities of the sample analysis system, it is desirable to transport samples at high speed, transport large quantities simultaneously, and transport them in multiple directions. In this respect, compared with the belt conveyor method mentioned above (1), the method of using electromagnetic attraction as thrust mentioned above (2) is advantageous and is under development.

[0004] In the method described in (2) above, a permanent magnet is placed on a container carrier such as a support for the sample, and the electromagnetic attraction generated by supplying current to the windings of a magnetic circuit disposed on the transfer surface is used as the thrust of the container carrier. The magnetic circuit is composed of teeth configured in a lattice shape and magnetic yokes connecting the teeth to each other. Some magnetic circuits also form the teeth and magnetic yokes as one unit.

[0005] For example, Patent Document 1 discloses the following: the teeth and the magnetic yoke are integrated, and the magnetic yoke is provided with magnetic circuits of different shapes with protrusions or concave parts, the protrusions and concave parts of the magnetic circuits are fitted together, thereby achieving good magnetic coupling, and a magnetic circuit with teeth arranged in a grid pattern is obtained.

[0006] Existing technical documents

[0007] Patent documents

[0008] Patent Document 1: Japanese Patent Application Publication No. 2016-075684 Summary of the Invention

[0009] The problem that the invention aims to solve

[0010] However, Patent Document 1 sets the cross-sectional areas of the teeth and the yoke to be equal according to conventional design rules. As a result, the cross-sectional area of ​​the yoke is greater than the minimum limit for non-magnetic saturation, and the weight of the conveying device increases.

[0011] The purpose of this invention is to provide a conveying device that can prevent magnetic saturation and reduce the weight of the conveying device, in view of the above.

[0012] One aspect of the present invention for solving the above-mentioned problems is a conveying device comprising: a conveying path for moving a conveyed object; an electromagnet disposed on a side of the conveying path opposite to the side on which the conveyed object moves; and a drive circuit for causing current to flow through the electromagnet, the electromagnet having teeth made of magnetic material and windings wound around the surface of the teeth, and a yoke provided with supporting the teeth, wherein the minimum cross-sectional area Sy of the yoke 26 is related to the minimum cross-sectional area St of the portion of the teeth where the windings are disposed in the condition Sy < St.

[0013] A more specific structure of the present invention is described in the claims.

[0014] The effects of the invention

[0015] According to the present invention, a conveying device can be provided that can reduce the weight of the conveying device while preventing magnetic saturation.

[0016] Other issues, structures, and effects not mentioned above will be clearly explained through the following implementation methods. Attached Figure Description

[0017] Figure 1 This is a schematic structural diagram illustrating an example of the conveying device of the present invention.

[0018] Figure 2 This is a cross-sectional schematic diagram comparing the structure of the conveying device.

[0019] Figure 3 This is a schematic cross-sectional view showing the cases where St = Sy and Sy < St in the conveying device.

[0020] Figure 4 It means in Figure 3 (a) and Figure 3 (b) Graph of thrust at various positions of the moving part.

[0021] Figure 5 This is a schematic cross-sectional view of the first example of the conveying device of Embodiment 2.

[0022] Figure 6 This is a schematic cross-sectional view of a second example of the conveying device of Embodiment 2.

[0023] Figure 7 This is a schematic cross-sectional view of the conveying device in Embodiment 3.

[0024] Figure 8 This is a schematic diagram showing the first example of the conveying device of Embodiment 4.

[0025] Figure 9 This is a schematic diagram showing a second example of the conveying device of Embodiment 4.

[0026] Figure 10This is a schematic cross-sectional view of the conveying device in Embodiment 5. Detailed Implementation

[0027] Hereinafter, embodiments of the present invention will be described using the accompanying drawings. Furthermore, the present invention is not limited to any particular embodiment; changes to the shape, configuration, or other structures are permitted as long as the desired effects of the present invention are achieved.

[0028] Example 1

[0029] Figure 1 This is a schematic structural diagram illustrating an example of the conveying device of the present invention. The conveying device 1 of the present invention includes: a conveying path (not shown) for moving a conveyed object 110; electromagnets 25a and 25b disposed on a side of the conveying path opposite to the side where the conveyed object moves; and drive circuits 50a and 50b for allowing current to flow through the electromagnets 25a and 25b. The drive circuits 50a and 50b are connected to a power supply 55. Current detection units 40a and 40b are disposed between the electromagnets 25a and 25b and the drive circuits 50a and 50b, and the current detection units 40a and 40b are respectively connected to an arithmetic unit 41. The structure will be described in detail below.

[0030] A permanent magnet (not shown) is built into the bottom surface of the conveyor 110. A conveying path (not shown) is provided between the conveyor 110 and the electromagnets 25a and 25b, and the conveyor 110 slides along the conveying path.

[0031] Examples of transporters 110 include sample holders that hold one sample container such as a test tube or sample unit containing a liquid sample or reagent, and sample racks that hold multiple sample containers. Neodymium alloys, ferrites, etc., are preferably used as permanent magnets in the transporters 110. Alternatively, soft magnetic materials may be used instead of permanent magnets, depending on the circumstances.

[0032] Electromagnets 25a and 25b have teeth 22a and 22b formed of magnetic material and windings 21a and 21b wound around the outer periphery of the teeth 22a and 22b. Figure 1 In the middle, the teeth 22a and 22b are cylindrical in shape, but are not limited to this and can also be prismatic.

[0033] The windings 21a and 21b of electromagnets 25a and 25b are connected to drive circuits 50a and 50b, respectively. Electromagnets 25a and 25b generate magnetic fields by voltages applied by drive circuits 50a and 50b. The magnetic fields are generated upwards from the upper ends of teeth 22a and 22b. These magnetic fields generate thrust on the permanent magnet of the conveyor 110.

[0034] Current detection units 40a and 40b are respectively equipped with the function of detecting the current flowing through the windings 21a and 21b of electromagnets 25a and 25b, and sending their current values ​​to the calculation unit 41. The calculation unit 41 uses the detected current values, etc., to output a control signal that moves the conveyor 110. As a result, the conveyor 110 can be conveyed to the desired position. In addition, the current detection units 40a and 40b can use components that measure the voltage of a series resistance, components based on current transformers, components using Hall current sensors, etc., but are not limited to these.

[0035] The calculation unit 41 calculates the relative positional relationship between the teeth 22a and 22b and the conveyed object 110 based on the current values ​​detected by the current detection units 40a and 40b, and calculates the position of the conveyed object 110 within the conveying device 1. Furthermore, the calculation unit 41 uses the calculated position information of the conveyed object 110 to determine the amount of current required to drive the conveyed object 110 and the timing of supplying that current.

[0036] A power supply 55 is connected to the drive circuits 50a and 50b. The power supply 55 can be AC ​​or DC. In the case of DC, a battery can also be used.

[0037] Next, an example of a moving device that uses electromagnetic force as described above will be explained. Figure 2 This is a cross-sectional schematic diagram comparing the structure of the conveying device. (Using...) Figure 2 As a conveying device other than the conveying device used in the analysis, the structure of the conveying device for the rotary machine / linear motor ( Figure 2 (a) and the structure of the conveying device of the present invention used in the analysis ( Figure 2 (b)) Compare and explain. Figure 2 (a) shows a rotary machine and a linear motor having a stator 20 and a mover 10. The stator 20 consists of teeth 22a and 22b, windings 21a and 21b wound thereon, and a yoke 26 supporting the teeth 22a and 22b. The mover 10 consists of a plurality of permanent magnets 11 arranged in a manner with different polarities and a mover core 12 in contact with the permanent magnets 11.

[0038] The mover 10 is close to the teeth 22a and 22b, and the mover core 12 is positioned across the teeth 22a and 22b. Therefore, most of the generated magnetic flux becomes the main magnetic flux 70, forming a loop between the teeth 22a, 22b, the yoke 26, and the mover 10. Consequently, the leakage magnetic flux between adjacent teeth 22a and 22b is very small, and the magnetic flux through the teeth 22a and 22b is equal to the magnetic flux through the yoke 26. Therefore, to suppress the reduction in the electromagnetic force driving the mover 10 due to magnetic saturation of either the teeth 22a, 22b, or the yoke 26, the cross-sectional area St of the wound portion of the teeth 22a and 22b needs to be equal to the cross-sectional area Sy of the yoke.

[0039] on the other hand, Figure 2 (b) The magnetic circuit of the conveying device shown passes through conveying path 65 (a non-magnetic body) between teeth 22a, 22b and the mover 10. Therefore, the distance between teeth 22a, 22b and the mover 10 is large, and the leakage flux 71 between adjacent teeth 22a and 22b is greater than that between adjacent teeth 22a and 22b. Figure 2 The magnetic flux passing through the yoke 26 is smaller than that passing through the teeth 22a and 22b, which are used in rotary machines, linear motors, etc. Therefore, even if the minimum cross-sectional area Sy of the yoke 26 is reduced relative to the cross-sectional area St of the teeth 22a and 22b, the electromagnetic force generated by the main magnetic flux 70 will not be affected. Therefore, the cross-sectional area of ​​the yoke 26 can be reduced within a range that does not cause magnetic saturation.

[0040] Figure 3 This is a schematic cross-sectional view showing the cases where St = Sy and Sy < St in the conveying device. Relative to Sy = St... Figure 3 (a), Figure 3 (b) The cross-sectional area Sy of the magnetic yoke 26 is reduced by decreasing its thickness in the z-axis direction (yoke thickness Wy). Additionally, Figure 4 It means Figure 3 (a) and Figure 3 (b) A graph showing the thrust at various positions of the mover. Figure 4 In this context, the area directly above tooth 22a is set to x = 0 (mm), and the area directly above tooth 22b is set to x = P (mm). For example... Figure 4 As shown, Figure 3 (a) The case of Sy = St and Figure 3 The thrust characteristics are consistent with the case where Sy < St in (b), therefore it can be concluded that even if the yoke 26 is thinned, it will not affect the main magnetic flux 70. Therefore, by setting Sy < St, one of the components constituting the magnetic circuit, namely the yoke 26, can be made lighter. By making the yoke 26 lighter, material costs can be reduced and manufacturing costs can be lowered. In addition, by making the yoke 26 lighter, the size of the conveying device can be reduced.

[0041] Example 2

[0042] Figure 5 This is a schematic cross-sectional view showing a first example of the conveying device of Embodiment 2. In Embodiment 1, the thickness of the magnetic yoke Wy is reduced so that Sy < St, but in this embodiment, as shown... Figure 5 (a) and Figure 5 As shown in (b), to make Sy < St, a recess 81 is provided to avoid areas requiring strength, thus locally reducing the cross-sectional area of ​​the yoke. Figure 5 In (a), a recess 81 is provided on the bottom surface of the magnetic yoke 26 (the surface opposite to the surface where the teeth 22a and 22b are mounted). Figure 5 In (b), a recess 81 is provided on the upper surface side of the magnetic yoke 26 (the side opposite to the surface where the teeth 22a and 22b are mounted). That is, the magnetic yoke 26 passes through the recess 81. Figure 5 (a) opens in the negative z-axis direction, in Figure 5 (b) The opening is in the positive z-axis direction. The recess 81 of the magnetic yoke 26 is set in such a way that the minimum cross-sectional area Sy of the magnetic yoke 26 and the minimum cross-sectional area St of the teeth 22a and 22b are in the form that Sy < St.

[0043] Because the recess 81 is provided in a way that avoids the tooth base portion 27, which serves as the connection between the teeth 22a, 22b and the yoke 26, the cross-sectional area of ​​the yoke 26 can be reduced while ensuring the strength of the tooth base portion 27, thus achieving weight reduction. However, the teeth 22a, 22b are fixed to the yoke 26 by pressing the tooth base portion 27 of the yoke with a clearance fit or by contacting the tooth mounting portion 30 with a tap, thereby magnetically coupling the teeth 22a, 22b and the yoke 26.

[0044] exist Figure 5 In (a), such as Figure 5 (a) is enlarged. Figure 5 As shown in (c), the surface area of ​​the negative z-axis side of the magnetic yoke 26 is increased by the amount of the tooth base surface 27a. Therefore, by providing a fan on the negative z-axis side, an improvement in the cooling efficiency of the magnetic circuit can be expected. Furthermore, in Figure 5 In (b), the recess 81 opens in the positive z-axis direction, so the area where the recess 81 is provided can be used as space for the winding 21. Therefore, the number of turns of the winding 21 can be increased without changing the size of the teeth 22a and 22b, thereby increasing the electromagnetic force used to drive the mover 10.

[0045] in addition, Figure 6 This is a schematic cross-sectional view showing a second example of the conveying device of Embodiment 2. Figure 6In (a), two recesses 81 are provided on the upper surface of the yoke 26 in a manner that avoids the tooth base portion 27 and the windings 21a and 21b. In the case where the conveying device is configured to apply force to a portion of the yoke 26, by providing the recesses 81 outside the parts where strength is required, weight can be reduced and strength can be ensured.

[0046] Figure 6 b indicates a configuration having both a recess 81a on the upper surface of the yoke 26 and a recess 81b on the bottom surface. For example... Figure 6 As shown in (b), the upper surface and the bottom recess of the magnetic yoke 26 can also be combined.

[0047] Example 3

[0048] Figure 7 This is a schematic cross-sectional view of the conveying device in Embodiment 3. Figure 7 This is a diagram of the magnetic circuit viewed from the positive z-axis. (For example...) Figure 7 As shown, in this embodiment, a recess 81 is provided on the side of the magnetic yoke 26 (horizontal direction (x-axis direction or y-axis direction)). Figure 7 In this case, by providing a recess 81 in the horizontal direction so that Sy < St, the same effect as in Example 1 can also be obtained.

[0049] exist Figure 7 In (a), the recess 81 is set to open in the positive y-axis direction with Sy < St, but the setting of the recess 81 is not limited. For example, as Figure 7 As shown in (b), Sy < St can also be achieved by combining recesses 81 that open in both the positive and negative y-axis directions. Additionally, the recesses 81 can also be as follows: Figure 7 (c) Setting them up differently from each other. Figure 7 In embodiment (c), by providing the recess 81 to avoid the tooth base portion, Sy can be reduced while ensuring the strength of the tooth base portion.

[0050] Example 4

[0051] Figure 8 This is a schematic cross-sectional view of the first example of the conveying device of Embodiment 3. Figure 9 This is a schematic diagram showing a second example of the conveying device of Embodiment 4. The shape of the recess is not limited to the shapes of Embodiments 2 and 3. Figure 8 and Figure 9 Example of representing the shape of a concave portion. It could also be like... Figure 8 (a) shows a concave section of a triangle, as... Figure 8 (b) shows a semi-circular concave section. Additionally, as... Figure 9As shown, the recess can also be provided with openings in both the vertical direction (z-axis direction) and the horizontal direction (either the x-axis or y-axis direction).

[0052] Example 5

[0053] Figure 10 This is a schematic cross-sectional view of the conveying device of Embodiment 5. In this embodiment, it shows the case where the yoke 26 has a hole 82 instead of a recess 81. The hole 82 is located inside the yoke and has a structure without an opening like the recess 81. By providing holes on the yoke 26 in a Sy < St manner, the same effect as in Embodiment 1 can be obtained. The number of holes 82 can be one or more. In addition, the cross-sectional shape of the hole 82 can be circular or quadrilateral, but is not limited to these.

[0054] As explained above, according to the present invention, a conveying device is provided that can prevent magnetic saturation and reduce the weight of the conveying device. The present invention is applicable to sample analysis systems and sample pretreatment devices for performing pretreatment required for analysis, etc.

[0055] Furthermore, the present invention is not limited to the above-described embodiments, but includes various modifications.

[0056] The above embodiments are described in detail for the purpose of readily understanding the present invention and are not intended to limit the invention to having all the structures described.

[0057] Alternatively, a portion of the structure of one embodiment can be replaced with the structure of another embodiment. Furthermore, structures from other embodiments can be added to the structure of one embodiment. Additionally, portions of the structure of each embodiment can be added to, deleted from, or replaced with other structures.

[0058] Symbol Explanation

[0059] 1… conveying device, 10… mover, 11… permanent magnet, 12… mover core, 20… stator, 21, 21a, 21b… windings, 22, 22a, 22b… teeth (second strong magnetic body), 25, 25a, 25b… electromagnet, 26… yoke, 27… tooth base of yoke, 27a… tooth base surface, 28… tooth cross-section, 29… yoke cross-section, 30… tooth mounting part, 40… current detection part, 41… calculation part, 50… drive circuit, 55… power supply, 60… position or speed detection part, 65… conveying path, 70… main magnetic flux, 71… leakage magnetic flux, 81, 81a, 81b… recesses provided in the yoke, 82… holes provided in the yoke, 110… conveyed object.

Claims

1. A conveying device, characterized in that, have: The conveyor is made of non-magnetic material and contains a permanent magnet or soft magnetic material, on which the conveyed object slides. An electromagnet is disposed on the side of the conveying path opposite to the surface on which the conveyed object moves; as well as A drive circuit that causes current to flow through the electromagnet. The electromagnet has multiple teeth made of magnetic material and a winding wound around the surface of the teeth. A magnetic yoke is provided to support the teeth. Among the plurality of teeth, the magnetic flux flowing in the yoke located directly below a pair of teeth is smaller than the magnetic flux flowing between adjacent pairs of teeth. The relationship between the minimum cross-sectional area Sy of the magnetic yoke and the minimum cross-sectional area St of the portion of the tooth where the winding is located is Sy < St.

2. The conveying device according to claim 1, characterized in that, The magnetic yoke has at least one recess, and the minimum cross-sectional area of ​​the at least one portion of the recess is the minimum cross-sectional area Sy of the magnetic yoke.

3. The conveying device according to claim 2, characterized in that, The recess is provided on the upper or bottom surface of the magnetic yoke.

4. The conveying device according to claim 2, characterized in that, The recess is provided on the side of the magnetic yoke.

5. The conveying device according to any one of claims 2 to 4, characterized in that, The recess opens toward the upper surface, bottom surface, or side surface of the magnetic yoke.

6. The conveying device according to claim 1, characterized in that, The magnetic yoke has at least one hole.

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