JP2022099892A - Cooling structure of linear motor and movable coil type linear motor with the cooling structure - Google Patents

Abstract

To provide a cooling structure of a linear motor which can be retrofitted to a movable coil type linear motor having no cooling function in a movable coil member itself, and exert high cooling performance even in the case of retrofit, and without leak of a coolant, and the movable coil type linear motor with the cooling structure.SOLUTION: A first jacket 1 is overlapped with a second jacket 2 in a mode of accommodating a movable coil member 3 in a communication part with which an air gap by a step part provided inside of each communicates, a coolant is supplied to the communication part to dissipate heat to be generated in a coil of the movable coil member 3. A flow channel of the coolant is provided by penetrating a stay 4.SELECTED DRAWING: Figure 2

Description

The present invention relates to a cooling structure for cooling a movable coil type linear motor, and a movable coil type linear motor provided with this cooling structure.

In a semiconductor manufacturing device, a liquid crystal manufacturing device, or an inspection device such as a semiconductor element or a liquid crystal display, a two-axis stage device, a so-called XY stage, is used as a transport mechanism for various parts. The XY stage includes an X stage that moves in a predetermined direction (X direction) with respect to the surface plate, and an Y stage that moves in a direction (Y direction) orthogonal to the X direction. Each of the X stage and the Y stage includes carriages that are moved by a drive unit, and a linear motor is used as a means for linearly moving these carriages in the X direction or the Y direction.

As an example of such a linear motor, an air core movable by combining a stator having a plurality of permanent magnets supported by a yoke and a mover having an air core coil in which a current flowing through the magnetic field of the permanent magnets flows. A coil type linear motor is used. In this movable coil type linear motor, it is common practice to increase the drive current flowing through the coil in order to move the carriage at high speed. When the drive current flowing through the coil increases, the amount of heat generated is proportional to the square of the current, so the characteristics of the linear motor may deteriorate due to an increase in the electrical resistance of the coil, magnetic deterioration of the permanent magnet, and the like. Therefore, it is necessary to perform cooling in order to suppress the temperature rise and maintain the stable characteristics of the linear motor.

As a method for cooling by flowing a refrigerant on the coil side, Patent Document 1 describes that both sides of a movable coil member formed by molding a coil with a resin are sandwiched between jackets, and the refrigerant is passed inside the movable coil member to drive the coil. A technique for suppressing the heat generation of a coil is disclosed.

Japanese Unexamined Patent Publication No. 2017-184492

In the linear motor disclosed in Patent Document 1, it is necessary to form a flow path of the refrigerant inside the movable coil member, and it is necessary to provide a special fitting structure between the movable coil member and the jacket. For this reason, each of the movable coil member and the jacket must be specially designed and manufactured, which causes a problem that the manufacturing cost increases.

By the way, as disclosed in, for example, Japanese Patent Application Laid-Open No. 2002-165434, there is also an air-core movable coil type linear motor in which the movable coil member itself does not have a cooling function by a refrigerant. In this movable coil type linear motor, a refrigerant passage is provided in a fixed plate for fixing the movable coil member to suppress a temperature rise. However, in this configuration, there is no flow path of the refrigerant capable of efficiently cooling the coil, and it is difficult to obtain a sufficient cooling effect.

The present invention has been made in view of such circumstances, and can be retrofitted to a movable coil type linear motor that does not have a cooling function in the movable coil member itself, and can exhibit high cooling performance even if it is retrofitted. It is an object of the present invention to provide a cooling structure of a linear motor without leakage of refrigerant, and a movable coil type linear motor provided with this cooling structure.

The cooling structure of the linear motor according to the present invention is a cooling structure of a linear motor that is retrofitted to a movable coil type linear motor provided with a movable coil member and for cooling the movable coil member by the flow of a refrigerant. A polymer is provided in which two jackets are superposed so that voids due to a step portion provided inside communicate with each other, and the movable coil member is housed in the communicating portion through which the voids of the polymer communicate. It is characterized in that the refrigerant is configured to flow to the communication portion.

In the cooling structure of the linear motor of the present invention, two jackets having a stepped portion are overlapped with each other, and a movable coil member is housed in a communicating portion of a polymer through which a gap is communicated by the stepped portion, and this communication is performed. A refrigerant is passed through the portion (accommodation area of the movable coil member) to cool the movable coil member. Therefore, it is possible to retrofit a moving coil type linear motor that does not have a cooling function in the movable coil member itself with a cooling structure that can achieve high cooling performance.

In the cooling structure of the linear motor according to the present invention, one end communicates with the injection port and the other end communicates with the communication portion with the first stay flow path of the refrigerant, and one end communicates with the discharge port and the other end communicates with the communication portion. Further includes a stay provided with a second stay flow path of the refrigerant, the first stay flow path penetrates the inside of the stay, and the first stay flow path, the communication portion, and the communication portion. It is characterized in that the refrigerant flows through the second stay flow path in this order.

The cooling structure of the linear motor of the present invention includes a stay having a first stay flow path that penetrates the inside and is connected to the communication portion of the polymer, and a second stay flow path that is connected to the communication portion of the polymer. Then, the refrigerant is circulated in the order of the first stay flow path, the polymer communication portion (accommodation area of the movable coil member), and the second stay flow path from the outside to cool the movable coil member. Since the refrigerant is also flowed into the stay close to the end of the movable coil member, high cooling performance can be obtained even at the coil end where the cooling performance is low only by the flow of the refrigerant inside the polymer.

The cooling structure of the linear motor according to the present invention is further provided with a stay provided with a flow path of the refrigerant penetrating the inside.

In the cooling structure of the linear motor of the present invention, the refrigerant is introduced into the flow path provided through the stay near the end of the movable coil member, independently of the flow of the refrigerant inside the polymer. Shed. Therefore, high cooling performance can be obtained even at the coil end portion where the cooling performance is low due to the flow of the refrigerant inside the polymer.

The cooling structure of the linear motor according to the present invention is characterized in that the two jackets are fastened with bolts.

In the cooling structure of the linear motor of the present invention, two jackets are fastened by bolts. Therefore, the sealing performance of the two jackets is high, and leakage of the refrigerant can be suppressed.

The cooling structure of the linear motor according to the present invention includes a contact portion between one of the two jackets and the movable coil member, a contact portion between the other of the two jackets and the movable coil member, and the two jackets. It is characterized in that an adhesive is applied to at least one contact portion of the contact portions between one and the other.

In the cooling structure of the linear motor of the present invention, at least one of the contact portion between one jacket and the movable coil member, the contact portion between the other jacket and the movable coil member, and the contact portion between both jackets. Adhesive is applied to the contact area. Therefore, the airtightness in sealing is further improved.

The movable coil type linear motor according to the present invention is characterized in that the cooling structure as described above is retrofitted.

In the movable coil type linear motor of the present invention, it is possible to retrofit a cooling structure having high cooling performance even for a type in which the movable coil member itself does not have a cooling function.

According to the present invention, it is possible to retrofit a cooling structure having high cooling performance to a movable coil type linear motor in which the movable coil member itself does not have a cooling function. Therefore, the temperature rise in the movable coil type linear motor can be easily suppressed.

It is an external perspective view which shows the structure of the cooling structure which concerns on this invention. It is an exploded perspective view which shows the structure of the cooling structure which concerns on this invention. It is a perspective view which shows the structure of the 1st jacket. It is a perspective view which shows the structure of the 2nd jacket. It is a perspective view which shows the structure of the 2nd jacket and a movable coil member. It is a perspective view which shows the structure of the 2nd jacket and a coil. It is a perspective view which shows the structure which overlapped the 1st jacket, the movable coil member, and the 2nd jacket. It is a partial fracture perspective view which shows the structure which overlapped the 1st jacket, the movable coil member, and the 2nd jacket. It is sectional drawing which shows the form which applied the adhesive. It is a schematic cross-sectional view which shows the cooling structure in the state which a refrigerant is flowing. It is an external view which shows the front side (the 1st jacket side) of the cooling structure of the linear motor by 1st Embodiment. It is an external view which shows the back side (second jacket side) of the cooling structure of the linear motor by 1st Embodiment. It is a perspective view which shows the structure of the 2nd jacket, the coil, and the stay in 1st Embodiment. It is a perspective view which shows typically the flow path of the refrigerant in 1st Embodiment. It is a figure which shows the temperature rise of each member in 1st Embodiment and a comparative example. It is an external view which shows the front side (the 1st jacket side) of the cooling structure of the linear motor by 2nd Embodiment. It is an external view which shows the back side (second jacket side) of the cooling structure of the linear motor by 2nd Embodiment. It is a perspective view which shows the structure of the 2nd jacket, the coil, and the stay in 2nd Embodiment. It is a perspective view which shows the structure of the 3rd Embodiment.

First, the configuration of an air-core movable coil type linear motor to which the cooling structure of the present invention is applied will be briefly described.

This movable coil type linear motor includes a stator and a mover. The stator alternates between a main magnet whose magnetization direction is orthogonal to the movable direction of the mover and a spacer magnet whose magnetization direction is parallel to the movable direction of the mover on one surface of a flat plate-shaped yoke made of a ferromagnetic material. It has a structure in which a pair of magnet rows forming a fixed structure are arranged facing each other.

On the other hand, the mover has a rectangular plate-shaped movable coil member formed by molding an air-core polyphase coil with a resin. Then, by passing a current through each coil, the mover linearly moves in the magnetic gap formed inside the stator due to the electromagnetic action between the magnetic flux generated in each coil and the magnet of the stator.

Hereinafter, the cooling structure according to the present invention will be specifically described with reference to the drawings showing the embodiments thereof.

1 and 2 are an external perspective view and an exploded perspective view showing the configuration of the cooling structure 10 according to the present invention, respectively. The cooling structure 10 includes a first jacket 1, a second jacket 2, a movable coil member 3, and a stay 4. The weight of the polymer 5 in which the first jacket 1, the movable coil member 3, and the second jacket 2 are stacked in order from the top, in other words, the movable coil member 3 is sandwiched between the first jacket 1 and the second jacket 2. A stay 4 is attached to the unit 5 to form a cooling structure 10.

FIG. 3 is a perspective view showing the configuration of the first jacket 1. The first jacket 1 has a rectangular plate shape, and step portions 11 are provided at one end in the width direction and both ends in the longitudinal direction of the first jacket 1. A gap 12 is formed inside the first jacket 1 by the step portion 11. On the bottom surface of the gap 12, six rectangular convex portions 13 are provided over two rows in the longitudinal direction, and through holes 14 are formed in each convex portion 13.

FIG. 4 is a perspective view showing the configuration of the second jacket 2, and the second jacket 2 has a rectangular plate shape having the same shape as the first jacket 1. Like the first jacket 1, the second jacket 2 is provided with stepped portions 21 at one end in the width direction and both ends in the longitudinal direction, and the stepped portion 21 creates a gap 22 inside the second jacket 2. It is formed. Further, on the bottom surface of the gap 12, six rectangular convex portions 23 are provided over two rows in the longitudinal direction at positions corresponding to the convex portions 13 and the through holes 14 of the first jacket 1, and each convex portion 23 is provided. Is formed with a screw hole 24. An insert nut may be provided instead of the convex portion 23 and the screw hole 24.

The first jacket 1 and the second jacket 2 are made of a material having high rigidity, electrical insulation, and water resistance, and are made of, for example, a glass epoxy resin.

FIG. 5 is a perspective view showing the configurations of the second jacket 2 and the movable coil member 3, and shows an embodiment in which the movable coil member 3 is placed on the second jacket 2. Further, FIG. 6 is a perspective view showing the configurations of the second jacket 2 and the coil 31, and the resin 32 for molding is shown from FIG. 5 so that the arrangement of the polyphase coil 31 in the movable coil member 3 becomes clear. Is shown.

As described above, the movable coil member 3 is formed by molding an air-core polyphase coil 31 (see FIG. 6) with a resin 32 to form a rectangular plate. In the movable coil member 3, six through holes 33 are formed in two rows in the longitudinal direction at positions corresponding to the through holes 14 and the screw holes 24 of the first jacket 1 and the second jacket 2.

For the resin 32, a material having high rigidity, electrical insulation, and water resistance is used, and for example, a glass epoxy resin is used. The multi-phase coil 31 is a three-phase coil, which is six flat-shaped air-core coils (U-phase coils (U1 to U2), V-phase coils (V1 to V2), and W-phase coils (W1 to W2). ) Are arranged so as not to overlap each other.

The first jacket 1 and the second jacket 2 are superposed to form the polymer 5 with the movable coil member 3 sandwiched between them. At this time, the gap 12 inside the first jacket 1 and the gap 22 inside the second jacket 2 communicate with each other so that the step portion 11 of the first jacket 1 and the step portion 21 of the second jacket 2 are joined. The movable coil member 3 is accommodated in the communication portion 51 (see FIG. 8) in which the first jacket 1 and the second jacket 2 are overlapped with each other and the gap 12 and the gap 22 communicate with each other.

7 and 8 are a perspective view and a partially broken perspective view showing a configuration in which the first jacket 1, the movable coil member 3, and the second jacket 2 are overlapped in this way.

The first jacket 1, the movable coil member 3, and the second jacket 2 are fastened through the bolt 6 through the through hole 14 of the first jacket 1, the through hole 33 of the movable coil member 3, and the screw hole 24 of the second jacket 2. The jacket.

An adhesive may be used in order to increase the degree of sealing of the polymer 5 in which these are superposed. FIG. 9 is a cross-sectional view showing a form in which the adhesive 7 is applied. A contact portion between the first jacket 1 and the second jacket 2 (one or both of the step portion 11 of the first jacket 1 and the step portion 21 of the second jacket 2), and a contact portion between the first jacket 1 and the movable coil member 3. And, the adhesive 7 is applied to the contact portion between the movable coil member 3 and the second jacket 2. As the adhesive 7, for example, a silicon-based material is used. The application of the adhesive 7 also contributes to the correction of flatness. The adhesive 7 is applied to all three contact portions, but if necessary, the adhesive 7 is applied to at least one of these three contact portions. It's fine.

The cooling process by the cooling structure 10 having the above-mentioned configuration will be described. FIG. 10 is a schematic cross-sectional view showing a cooling structure 10 in a state where the refrigerant 8 is flowing.

The refrigerant 8 (hatched in FIG. 10 is shown in the region where the movable coil member 3 is housed, that is, the communication portion 51 in which the gap 12 inside the first jacket 1 and the gap 22 inside the second jacket 2 communicate with each other. ). At this time, a part of the refrigerant 8 flows through the through hole 33 of the movable coil member 3. The refrigerant 8 flowing at a position close to the outer peripheral surface of the coil 31 makes it possible to remove heat generated from the outer peripheral surface of the coil 31, and suppresses a temperature rise in the coil 31 itself and its peripheral portion.

As the refrigerant 8 to be used, a liquid that is thermally and chemically stable, is nonflammable, nontoxic, odorless, and has excellent environmental resistance is effective. From the viewpoint of environmental resistance, a natural refrigerant (water) is preferable, while a fluorine-based inert liquid is preferable when heat transferability is taken into consideration.

Hereinafter, some embodiments of the present invention in which the flow path configurations of the refrigerant 8 are different will be described.

(First Embodiment)
In the first embodiment, the stay 4 is included as the cooling structure 10, and the refrigerant 8 is continuously flowed in the polymer 5 and the stay 4. FIG. 11 is an external view showing the front side (first jacket 1 side) of the cooling structure 10 according to the first embodiment, and FIG. 12 is an external view showing the back side (second jacket 2 side) of the cooling structure 10 as well. Is. Further, FIG. 13 is a perspective view showing the configuration of the second jacket 2, the coil 31, and the stay 4 in the first embodiment. Further, FIG. 14 is a perspective view schematically showing the flow path of the refrigerant 8 in the first embodiment.

The stay 4 for attaching the mover (movable coil member 3) to the external device to be driven has a substantially rectangular parallelepiped shape, and is provided along the longitudinal direction thereof along the longitudinal direction of the polymer 5. The stay 4 and the polymer 5 are fastened by screwing with a bolt 9 from the side surface of the stay 4 (see FIG. 12). The plurality of holes 41 found on the upper surface (FIG. 11) and the side surface (FIG. 12) of the stay 4 are holes used when connecting to an external device. The stay 4 is made of, for example, aluminum.

The stay 4 is provided with a long first stay flow path 42 that penetrates the stay 4 in the longitudinal direction and a short second stay flow path 43 formed at one end of the stay 4 (a short second stay flow path 43). See FIG. 14). One end of the first stay flow path 42 is connected to an injection port 44 provided at one end of the stay 4, and the other end of the first stay flow path 42 is a communication of the polymer 5 in which the movable coil member 3 is housed. It communicates with one side of the portion 51. On the other hand, one end of the second stay flow path 43 is connected to the discharge port 45 provided at one end of the stay 4, and the other end of the second stay flow path 42 is the polymer 5 in which the movable coil member 3 is housed. It communicates with the other side of the communication portion 51 of. With such a configuration, as a flow path of the refrigerant 8, as shown in FIG. 14, in order from the upstream side, the injection port 44, the first stay flow path 42, the communication portion 51 of the polymer 5, and the second stay flow path 43. , And a flow path leading to the discharge port 45, and the refrigerant 8 flows in this flow path. Then, the movable coil member 3 (coil 31) is cooled by the flow of the refrigerant 8.

In this first embodiment, the flow path in the stay 4 close to one end of the coil 31, which is considered that the refrigerant 8 cannot be sufficiently reached by the flow of the refrigerant 8 in the polymer 5. Since (the first stay flow path 42) is provided, high cooling performance can be achieved for the coil 31 even in this portion.

The coil 31 was energized in the configuration provided with the cooling structure 10 according to the first embodiment (example of the present invention), and the temperature rise Δt of each component (coil 31, stay 4, resin 32) was measured. Further, the coil was energized in a configuration (comparative example) not provided with such a cooling structure, and the temperature rise Δt of each component (coil, stay, resin) was measured. The results of these measurements are shown in FIG.

From the measurement results shown in FIG. 15, it is understood that in the example of the present invention, the temperature rise due to heat generation is small and high cooling performance can be exhibited.

(Second Embodiment)
The second embodiment is a form in which the refrigerant 8 flows only inside the polymer 5. FIG. 16 is an external view showing the front side (first jacket 1 side) of the cooling structure 10 according to the second embodiment, and FIG. 17 is an external view showing the back side (second jacket 2 side) of the cooling structure 10 as well. Is. Further, FIG. 18 is a perspective view showing the configuration of the second jacket 2, the coil 31, and the stay 4 in the second embodiment. In FIGS. 16 to 18, the same or similar components as those in FIGS. 11 to 13 are numbered the same.

In the second embodiment, the flow path is not provided in the stay 4 as in the first embodiment, and the injection port 15 and the discharge port 25 are provided in communication with the communication portion 51 of the polymer 5. There is. With such a configuration, as a flow path of the refrigerant 8, a flow path leading to the injection port 15, the communication portion 51 of the polymer 5, and the discharge port 25 is configured in order from the upstream side, and the inside of this flow path is filled with the refrigerant. 8 flows. Then, the movable coil member 3 (coil 31) is cooled by the flow of the refrigerant 8.

In the second embodiment, since the stay 4 does not form a flow path, the cooling performance can be exhibited with a simple configuration.

(Third Embodiment)
The third embodiment includes the stay 4 as the cooling structure 10, and the flow path of the refrigerant 8 is independently provided in the stay 4 and in the polymer 5. FIG. 19 is a perspective view showing a third embodiment. In FIG. 19, the same or similar components as those in FIGS. 11 and 16 are numbered the same.

The stay 4 having a substantially rectangular parallelepiped shape is provided with a stay flow path 46 that penetrates the stay 4 in the longitudinal direction. One end of the stay flow path 46 is connected to an injection port 44 provided at one end of the stay 4, and the other end of the stay flow path 46 is connected to the discharge port 45 provided at the other end of the stay 4. With such a configuration, the refrigerant 8 flows from the injection port 44 to the discharge port 45 via the stay flow path 46.

Further, similarly to the second embodiment, the injection port 15 and the discharge port 25 communicating with the communication portion 51 of the polymer 5 are provided. Then, as in the second embodiment, the refrigerant 8 flows in order from the upstream side through the injection port 15, the communication portion 51 of the polymer 5, and the discharge port 25. As described above, the third embodiment can be said to be a form in which the flow path in the stay 4 is independently added to the second embodiment.

In the third embodiment, the movable coil member 3 (coil 31) is cooled by the flow of the refrigerant 8 in the polymer 5 and the flow of the refrigerant 8 in the stay 4 (stay flow path 46). In the third embodiment, as in the first embodiment, since the refrigerant 8 flows into the stay 4 close to one end of the coil 31, the cooling of the coil 31 is high even in this portion. It can demonstrate its performance. Further, since the flow path of the refrigerant 8 is divided into two systems, the refrigerant 8 flowing through each flow path can be controlled independently, so that the flow rate of the refrigerant 8 can be adjusted with high accuracy according to each flow path. Is possible.

As described above, in the movable coil member 3 of the present invention, it is not necessary to form a flow path for the refrigerant, and an insert nut for fixing the jacket as seen in the movable coil member in Patent Document 1 is provided. Moreover, since no special member for being fitted to the first jacket 1 and the second jacket 2 is required, it can be manufactured at low cost. Further, in the cooling structure 10 of the present invention, since the movable coil member 3 does not require a special configuration as described above, the cooling structure 10 is applicable to various movable coil type linear motors having no cooling function. Is expensive.

Further, in the cooling structure 10 of the present invention, since the polymer 5 is highly airtight, the refrigerant 8 does not leak and high cooling performance can be exhibited. Further, the cooling structure 10 of the present invention can be easily retrofitted to various types of movable coil type linear motors.

In the above-described embodiment, the first jacket 1, the movable coil member 3, and the second jacket 2 are fastened by using the bolt 6, but this fixing mechanism is an example, for example, the first jacket. 1. Other fixing mechanisms may be used, such as sandwiching the movable coil member 3 and the second jacket 2 with clamp members to fix them.

In the above-described embodiment, the movable coil member 3 is configured by molding the coil 31 with the resin 32. However, the configuration of the movable coil member 3 is an example, and the movable coil member having another configuration is used. The cooling structure of the present invention can also be applied to a movable coil type linear motor having.

The disclosed embodiments should be considered exemplary in all respects and not restrictive. The scope of the present invention is shown by the scope of claims rather than the above description, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

1 1st jacket 2 2nd jacket 3 Movable coil member 4 Stay 5 Polymer 6 Bolt 7 Adhesive 8 Refrigerant 10 Cooling structure 11, 21 Steps 12, 22 Voids 13, 23 Convex 14 Through holes 15 Injection port 24 Screw holes 25 Outlet 31 Coil 32 Resin 33 Through hole 41 Hole 42 1st stay flow path 43 2nd stay flow path 44 Injection port 45 Outlet 46 Stay flow path 51 Communication part

Claims (6)

It is a cooling structure of a linear motor that is retrofitted to a movable coil type linear motor provided with a movable coil member and for cooling the movable coil member by the flow of a refrigerant.
It is provided with a polymer in which two jackets are overlapped so that the voids due to the stepped portions provided inside each communicate with each other, and the movable coil member is housed in the communicating portion through which the voids of the polymer communicate. The cooling structure of the linear motor is configured to allow the refrigerant to flow through the communication portion. The first stay flow path of the refrigerant having one end connected to the inlet and the other end communicating with the communication portion, and the second stay flow path of the refrigerant having one end connected to the discharge port and the other end communicating with the communication portion. The stay is further provided, and the first stay flow path penetrates the inside of the stay, and the refrigerant is in this order in the first stay flow path, the communication portion, and the second stay flow path. The cooling structure for a linear motor according to claim 1, wherein the linear motor is configured to flow. The cooling structure for a linear motor according to claim 1, further comprising a stay provided with a flow path of the refrigerant penetrating the inside. The cooling structure for a linear motor according to any one of claims 1 to 3, wherein the two jackets are fastened with bolts. At least one of the contact portion between one of the two jackets and the movable coil member, the contact portion between the other of the two jackets and the movable coil member, and the contact portion between one of the two jackets and the other. The cooling structure for a linear motor according to any one of claims 1 to 4, wherein an adhesive is applied to one contact portion. A movable coil type linear motor, characterized in that the cooling structure of the linear motor according to any one of claims 1 to 5 is retrofitted.

Images