WO2015097879A1

WO2015097879A1 - Linear motion device

Info

Publication number: WO2015097879A1
Application number: PCT/JP2013/085157
Authority: WO
Inventors: 田中　克明; 正明菅野
Original assignee: 富士機械製造株式会社
Priority date: 2013-12-27
Filing date: 2013-12-27
Publication date: 2015-07-02
Also published as: JPWO2015097879A1; JP6302488B2

Abstract

A linear motion device is provided with: a linear motor having a stator and a mover; cooling means provided to the mover of the linear motor; a detection means for detecting whether each of the cooling means is normal or not; and a control means for controlling the operation of the mover of the linear motor according to a predetermined control index. The control means is configured so as to change the control index when the detection means detects the abnormality of at least one of the cooling means.

Description

Linear motion device

The technology disclosed herein relates to a linear motion device having a linear motor, and more particularly to a linear motion device in which a plurality of cooling means are provided on a mover of the linear motor.

Linear motion devices having linear motors are widely used in production devices such as electronic component mounting machines (also called chip mounters) and other devices. In this type of linear motion device, a plurality of cooling fans (or other cooling means) are provided on the mover of the linear motor. The plurality of cooling fans mainly cool the electromagnetic coils provided in the mover.

In the linear motion device described above, if the cooling fan fails, the electromagnetic coil may overheat and burn out. One measure for preventing this is to immediately stop the operation of the linear motion device when an abnormality occurs in the cooling fan. However, in a production apparatus such as an electronic component mounting machine, if the operation of the linear motion apparatus is stopped immediately, the production apparatus may stop in the middle of a series of production operations. In this case, there arises a problem that a semi-finished product that is in the middle of production is wasted or subsequent recovery work becomes troublesome.

In relation to the above problem, Japanese Patent Application Laid-Open No. 2002-16387 describes a cooling device used for an electronic component mounting machine. This cooling device has a plurality of cooling fans, and is configured to increase the rotation speed of other cooling fans when an abnormality occurs in one cooling fan. Such a cooling device can also be employed in a linear motion device, whereby it is considered that the operation of the linear motion device can be continued even when a failure occurs in the cooling fan.

However, many linear motion devices do not inherently have a means for controlling the rotational speed of the cooling fan. For this reason, in order to employ the technique described in Japanese Patent Laid-Open No. 2002-16387, it is necessary to newly provide a configuration for controlling the rotational speed of the cooling fan, which increases the production cost of the linear motion device, for example. A new problem arises.

This specification discloses a novel and useful linear motion apparatus in order to provide a technique for solving or at least reducing the above-described problems.

In the technology disclosed in this specification, whether or not each of the plurality of cooling means is normal is monitored, and when an abnormality occurs in at least one cooling means, a control index used for controlling the mover is movable. Change so that the calorific value of the child is reduced. Thereby, even when an abnormality occurs in some or all of the plurality of cooling units, the operation of the mover can be continued while suppressing overheating of the mover. Here, typical examples of the control index of the mover include the maximum acceleration, maximum deceleration, and maximum speed of the mover of the mover.

Based on this technology described above, a new and useful linear motion device is disclosed. This linear motion device detects whether each of a linear motor having a stator and a mover, a plurality of cooling means provided on the mover of the linear motor, and a plurality of cooling devices is normal. Means and control means for controlling the operation of the mover of the linear motor in accordance with a predetermined control index. The control means changes the control index when the detection means detects an abnormality of at least one cooling means. In this case, the control index is preferably changed so that the amount of heat generated in the mover is reduced.

In one embodiment of the present technology, it is preferable that at least one of the maximum acceleration, the maximum deceleration, and the maximum speed of the mover is changed to be small as the control index. In the linear motor, the amount of heat generated by the mover (particularly, the amount of heat generated by the electromagnetic coil) increases in accordance with the maximum acceleration, maximum deceleration, and maximum speed of the mover. Therefore, when an abnormality occurs in one or more cooling means, the overheating of the mover is effectively reduced by reducing at least one (preferably all) of the maximum acceleration, maximum deceleration and maximum speed. Can be prevented.

FIG. 1 is a plan view schematically showing a linear motion device according to an embodiment. FIG. 2 is an elevational view schematically showing the linear motion device of the embodiment. FIG. 3 is a block diagram illustrating an electrical configuration of the linear motion device according to the embodiment. FIG. 4 shows an example of the control index stored in the memory of the servo controller. FIG. 5 shows an example of the reference data stored in the memory of the servo controller.

In one embodiment of the present technology, it is preferable that the control unit changes the control index of the mover when the detection unit detects an abnormality in the first predetermined number or more of the cooling units. Here, the first predetermined number may be 1, 2, or more, and may be determined according to the cooling capacity of each cooling means, for example.

In one embodiment of the present technology, it is preferable that the control unit stops the operation of the mover when the detection unit detects an abnormality with respect to the second predetermined number or more of cooling units larger than the first predetermined number. . According to such a configuration, when abnormalities occur in many cooling means and the cooling capacity of the mover is greatly reduced, it is possible to reliably avoid overheating of the mover by stopping the operation of the mover. it can.

In one embodiment of the present technology, the control unit may change the control index of the mover when the detection unit detects an abnormality with respect to one or more specific cooling devices. Such a configuration is effective when a plurality of cooling means have different cooling capacities. For example, when a plurality of cooling means includes a main cooling means having a relatively large cooling capacity and a secondary cooling means having a relatively small cooling capacity, if the main cooling means has an abnormality, the plurality of cooling means The overall cooling capacity by means is greatly reduced. In such a case, it is preferable that the control means changes the control index in order to prevent the mover from being overheated.

In one embodiment of the present technology, it is preferable that the control unit includes a storage unit that stores reference data that describes whether or not the control index needs to be changed for each combination of normality and abnormality of the plurality of cooling units. In this case, the control means preferably changes the control index of the mover based on the detection result by the detection means and the reference data stored in the storage means. According to such a configuration, it is possible to appropriately change the control index of the mover in accordance with the state of abnormality occurring in the plurality of cooling means.

In one embodiment of the present technology, it is preferable that the linear motion device further includes display means. In this case, the display means preferably displays the cooling means in which an abnormality has occurred based on the detection result by the detection means. Alternatively, the display means preferably displays that when the control means changes the control index.

In one embodiment of the present technology, each of the plurality of cooling means is preferably a blower having a cooling fan. However, the cooling means is not limited to the blower, and for example, cooling water may be circulated.

In the above-described embodiment, the detection unit detects the number of rotations of the cooling fan per unit time (in other words, the rotation speed or the rotation frequency, hereinafter simply referred to as the number of rotations) for each of the plurality of cooling units. It is preferable to have a sensor. According to such a configuration, the detection means can determine whether or not the cooling means is abnormal based on the rotational speed detected by the sensor.

The linear motion device 10 according to the embodiment will be described with reference to the drawings. The linear motion device 10 of the present embodiment can be employed as an actuator in a production device such as an electronic component mounting machine (also referred to as a chip mounter) or other devices. As shown in FIGS. 1 and 2, the linear motion device 10 includes a linear motor 12 having a stator 20 and a mover 30, and is a linear motion device driven by the linear motor 12.

The stator 20 of the linear motor 12 extends linearly along the moving path of the mover 30. The stator 20 is provided with a plurality of permanent magnets 22. The plurality of permanent magnets 22 are arranged in series along the longitudinal direction of the stator 20. The stator 20 may be curved along the longitudinal direction.

The mover 30 of the linear motor 12 is supported so as to be movable along the longitudinal direction of the stator 20. The mover 30 is provided with an electromagnetic coil 32, a temperature sensor 34, and a position sensor 36. An alternating current is applied to the electromagnetic coil 32, whereby the mover 30 moves along the stator 20. The temperature sensor 34 detects the temperature of the electromagnetic coil 32. Although the temperature sensor 34 in a present Example is not specifically limited, It is a thermistor. Since the electromagnetic coil 32 generates heat when energized, the temperature of the electromagnetic coil 32 is monitored by the temperature sensor 34 in order to prevent the electromagnetic coil 32 from overheating. The position sensor 36 detects the position of the mover 30 with respect to the stator 20. The position sensor 36 in the present embodiment is not particularly limited, but is a linear scale.

The linear motion device 10 includes a plurality of cooling devices 41 to 44. The plurality of cooling devices 41 to 44 are provided in the mover 30 and cool the mover 30 (in particular, the electromagnetic coil 32). The number of the plurality of cooling devices 41 to 44 is not particularly limited. As an example, this embodiment includes four cooling devices 41 to 44 including a first cooling device 41, a second cooling device 42, a third cooling device 43, and a fourth cooling device 44. . Each of the cooling devices 41 to 44 is a blower having a cooling fan 40. Although it is an example, the 1st and

2nd cooling devices

41 and 42 ventilate from the inside of mover 30 to the outside, and the 3rd and

4th cooling devices

43 and 44 ventilate from the outside of mover 30 to the inside. .

Although not shown in FIGS. 1 and 2, the first to fourth cooling devices 41 to 44 are provided with first to fourth abnormality sensors 51 to 54 (see FIG. 3). The first abnormality sensor 51 is a sensor for detecting whether or not the first blower 41 is normal. Similarly, the second to fourth abnormality sensors 52 to 54 are sensors for detecting whether or not the second to fourth cooling devices 42 to 44 are normal. The specific configuration of the abnormality sensors 51 to 54 is not particularly limited. As an example, the abnormality sensors 51 to 54 in the present embodiment are rotation speed sensors that detect the rotation speed of the cooling fan 40.

The linear motion device 10 includes a control unit 60. The control unit 60 controls the operation of the linear motion device 10. The control unit 60 is electrically connected to the mover 30 of the linear motor 12 via the electric cable 70.

The electrical configuration of the linear motion device 10 will be described with reference to FIG. As shown in FIG. 3, the control unit 60 includes a servo controller 62 and a servo amplifier 66. The servo controller 62 and the servo amplifier 66 are an example of a control unit that controls the operation of the mover 30. The servo amplifier 66 is connected to the position sensor 36. The servo controller 62 calculates the target movement of the mover 30 based on a command from the outside and teaches it to the servo amplifier 66. The servo amplifier 66 controls the mover 30 based on the target movement of the mover 30 taught from the servo controller 62 and the position of the mover 30 detected by the position sensor 36. Specifically, the servo amplifier 66 controls the magnitude and direction of the current supplied to the electromagnetic coil 32 based on the deviation between the target motion of the mover 30 and the actual motion.

The servo controller 62 has a memory 64. The memory 64 stores various data used for controlling the mover 30. For example, the memory 64 stores a control index for the mover 30. The control index of the mover 30 is an index used in the control of the mover 30, for example, the maximum acceleration, the maximum speed, and the maximum deceleration of the mover 30. The servo controller 62 and the servo amplifier 66 control the operation of the mover 30 according to the control index stored in the memory 64. Thereby, the acceleration, speed, and deceleration when the mover 30 moves are limited to each maximum value or less stored in the memory 64, and thereby, for example, overheating of the mover 30 (particularly, the electromagnetic coil 32) is prevented. Is prevented. As will be described in detail later, the memory 64 stores a plurality of sets of control indexes including a set of control indexes for the normal mode and a set of control indexes for the heat control mode.

The control unit 60 includes an abnormality detection unit 68. The abnormality detection unit 68 is connected to the first to fourth abnormality sensors 51 to 54, and based on the output signals from the first to fourth abnormality sensors 51 to 54, the first to fourth cooling devices 41 to 44 are connected. Whether or not is normal is detected. In the present embodiment, the output signals of the first to fourth abnormality sensors 51 to 54 indicate the rotation speeds of the cooling fans 40 in the first to fourth cooling devices 41 to 44, respectively. Accordingly, the abnormality detection unit 68 determines that an abnormality has occurred in the first to fourth cooling devices 41 to 44 when the rotational speed indicated by the output signals of the first to fourth abnormality sensors 51 to 54 has decreased below a predetermined value. to decide. The abnormality detection unit 68 is connected to the servo controller 62, and the determination result by the abnormality detection unit 68 is taught to the servo controller 62.

The servo controller 62 shifts from the normal mode to the heat control mode and switches the control index to be used when an abnormality occurs in one of the first to fourth cooling devices 41 to 44. FIG. 4 shows an example of a control index for the normal mode (maximum acceleration, maximum speed, and maximum deceleration) and a control index for the heat control mode. As shown in FIG. 4, the maximum acceleration A2 for the heat control mode is smaller than the maximum acceleration A1 for the normal mode. Similarly, the maximum speed V2 and the maximum deceleration D2 for the heat control mode are smaller than the maximum speed V1 and the maximum deceleration D1 for the normal mode, respectively. Therefore, in the control in the heat control mode, the heat generation of the mover 30 can be suppressed compared to the control in the normal mode. Thus, even when an abnormality occurs in one of the first to fourth cooling devices 41 to 44, the linear motion device 10 can continue its operation while preventing the mover 30 from being overheated. In the transition from the normal mode to the heat control mode, not all of the maximum acceleration, the maximum speed, and the maximum deceleration, but at least one of them may be changed.

On the other hand, the servo controller 62 immediately stops the operation of the mover 30 when abnormality occurs in two or more of the first to fourth cooling devices 41 to 44. In such a case, the cooling capacity is insufficient with only the remaining cooling devices 41 to 44 even in the heat control mode. However, even when abnormality occurs in two or more of the first to fourth cooling devices 41 to 44, it is not always necessary to shift to the heat control mode when the cooling capacity is sufficient.

The abnormality detection unit 68 is also connected to the temperature sensor 34, and determines that the temperature of the mover 30 is abnormal when the temperature detected by the temperature sensor 34 exceeds a predetermined value. This determination result is also taught to the servo controller 62. The servo controller 62 immediately stops the operation of the mover 30 even when the temperature of the mover 30 is abnormal.

The control unit 60 includes a display unit 69. Although the display unit 69 is not particularly limited, the display unit 69 includes a liquid crystal display panel. The display unit 69 is connected to the abnormality detection unit 68 and displays the cooling devices 41 to 44 in which an abnormality has occurred. As a result, the operator can easily repair or replace the cooling devices 41 to 44 in which an abnormality has occurred. The display unit 69 is also connected to the servo controller 62. When the servo controller 62 shifts from the normal mode to the heat control mode (that is, when the control index is changed), the display unit 69 displays that effect. Thereby, the worker can quickly recognize that the operation of the linear motion device 10 is restricted.

As described above, the linear motion device 10 according to the present embodiment shifts to the heat control mode in which the heat generation amount of the mover 30 is small when an abnormality occurs in a part of the plurality of cooling devices 41 to 44. The operation of the mover 30 can be continued. In addition, the linear motion device 10 of this embodiment ensures that the mover 30 is overheated by immediately stopping the operation of the mover 30 when an abnormality occurs in many of the cooling devices 41 to 44. Can be prevented.

Although specific examples of the present invention have been described in detail above, these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above.

In another embodiment of the present technology, when the servo controller 62 detects an abnormality in the first predetermined number or more of the cooling devices 41 to 44, the normal mode may be shifted to the heat control mode. Similarly, the operation of the mover 30 may be stopped when the servo controller 62 detects an abnormality with respect to the second predetermined number or more of the cooling devices 41 to 44 larger than the first predetermined number. In this case, the first predetermined number is not limited to one and may be two or more. Similarly, the second predetermined number is not limited to two and may be three or more.

In another embodiment of the present technology, the memory 64 of the servo controller 62 may store reference data as shown in FIG. The reference data shown in FIG. 5 describes whether or not the control mode needs to be changed (that is, whether or not the control index needs to be changed) for each combination of normality and abnormality of the plurality of cooling devices 41 to 44. The servo controller 62 may perform a transition from the normal mode to the heat control mode (that is, change of the control index) based on the determination result by the abnormality detection unit 68 and the reference data. According to such a configuration, the servo controller 62 shifts from the normal mode to the heat control mode (ie, the control index) when the abnormality detection unit 68 detects an abnormality in the specific one or more cooling devices 41 to 44. Change).

The technical elements described in the present specification or drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology illustrated in the present specification or the drawings achieves a plurality of objects at the same time, and has technical utility by achieving one of the objects.

10: linear motion device 12: linear motor 20: stator 22: permanent magnet 30: mover 32: electromagnetic coil 34: temperature sensor 36: position sensor 40: cooling fans 41 to 44: first to fourth cooling devices 51 to 54: first to fourth abnormality sensors 60: control unit 62: servo controller 64: memory 66: servo amplifier 68: abnormality detection unit 69: display unit 70: electric cable

Claims

A linear motion device,
A linear motor having a stator and a mover;
A plurality of cooling means provided on the mover of the linear motor;
Detecting means for detecting whether each of the plurality of cooling means is normal;
Control means for controlling the operation of the mover of the linear motor according to a predetermined control index;
With
The control means changes the control index when the detection means detects an abnormality of at least one cooling means.
Linear motion device.
The linear motion apparatus according to claim 1, wherein the control means changes, as the control index, at least one of a maximum acceleration, a maximum speed, and a maximum deceleration of the mover to be small.
The linear motion apparatus according to claim 1, wherein the control means changes all of the maximum acceleration, the maximum speed, and the maximum deceleration of the mover to be small as the control index.
The linear motion according to any one of claims 1 to 3, wherein the control means changes a control index of the mover when the detection means detects an abnormality in the first predetermined number or more of cooling means. apparatus.
5. The linear motion according to claim 4, wherein the control unit prohibits the operation of the mover when the detection unit detects an abnormality in a second predetermined number or more of cooling units greater than the first predetermined number. apparatus.
The linear motion according to any one of claims 1 to 3, wherein the control unit changes a control index of the mover when the detection unit detects an abnormality with respect to one or more specific cooling units. apparatus.
The control means includes storage means for storing reference data describing whether or not the control index needs to be changed for each combination of normality and abnormality of the plurality of cooling means, and the detection result by the detection means, The linear motion apparatus according to claim 6, wherein a control index of the mover is changed based on reference data.
The linear motion device according to any one of claims 1 to 7, further comprising display means for displaying a cooling means in which an abnormality has occurred based on a detection result by the detection means.
The linear motion device according to any one of claims 1 to 8, further comprising display means for displaying when the control means changes the control index.
The linear motion device according to any one of claims 1 to 9, wherein each of the plurality of cooling means is a blower having a cooling fan.
The linear motion device according to claim 10, wherein the detection unit includes a sensor that detects the number of rotations of the cooling fan per unit time for each of the plurality of cooling units.