JPH08168232A - Linear encoder device - Google Patents

Abstract

PURPOSE: To obviate the mechanical connection between a linear encoder device and a liner synchronous motor, by integrally installing on the liner synchronous motor side a detection unit for detecting the magnetic field generated by the motor. CONSTITUTION: A linear encoder device is integrated with a linear synchronous motor 2. The stator 23 of the linear synchronous motor 2 includes a yoke 24 that extends in the direction of the movement of a movable element 21 and constitutes a base. Permanent magnets 25 of different polarity that are alternately placed in the direction of the movement at a constant interval. Provided with coils 22, the movable element 21 is installed in such a way that it can travel with a constant gap 26 maintained between it and the permanent magnets 25. The encoder device 1 includes a detection unit 11 installed on the movable element 21 side, and the unit is positioned at the end of the movable element 21 in the direction of movement. When the linear synchronous motor 2 is driven, the movable element 21 is moved along the stator 23. While the movable element is moving, variation in magnetic field is detected and the information on the movement of the linear synchronous motor 2 is output. This obviates the mechanical connection between the linear encoder device and the linear synchronous motor.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linear encoder device, and more particularly to a linear encoder device for detecting the position of a linear synchronous motor.

[0002]

2. Description of the Related Art Generally, a linear synchronous motor is known as a driving device for giving a linear motion or a reciprocating motion by an electromagnetic force, and a linear synchronous motor is used as a detecting device for obtaining the position of a moving body performing the linear motion or the reciprocating motion. Encoder devices are known. In addition, in the conventional linear synchronous motor, a separate independent linear encoder is provided side by side in order to obtain information about the position moved by this linear synchronous motor, the moving speed, and the magnetic pole position for determining the current phase. FIG. 10 is a diagram for explaining the configuration of a linear encoder device installed in a conventional linear synchronous motor. In FIG. 10, the linear synchronous motor 6 includes a fixed portion 63 in which a plurality of coils 64 are arranged,
The permanent magnet 62 is installed in the movable portion 61, and the movable portion 61 is driven by sequentially switching the excitation of the coil 64 on the fixed portion 63 side.

In order to know the moving position, moving speed, and magnetic pole position of the linear synchronous motor 6, a linear encoder 5 is installed side by side. The linear encoder 5 includes, for example, a fixed portion 53 in which the detection portion 54 is arranged and a movable portion 51 in which the permanent magnet 52 is installed, and the permanent magnet 5 according to the movement of the movable portion 51.
The magnetic field change 2 is detected by the detection unit 54. Then, the linear encoder 5 and the linear synchronous motor 6 are mechanically connected by the coupling portion 7, and the movement of the movable portion 61 by the linear synchronous motor 6 is transmitted to the movable portion 51 of the linear encoder 5, so that the linear encoder The moving state of the synchronous motor is detected. The configuration of the linear synchronous motor and the linear encoder is an example, and various other configurations are known.

[0004]

However, the conventional linear encoder device has a problem in that a separate linear encoder is required for the linear synchronous motor, and they must be mechanically connected. There is. Due to such a configuration, in the conventional linear encoder device, there is a problem that the device becomes large and the number of components increases, and the phase between the magnetic field in the linear synchronous motor and the detection output by the linear encoder is increased. There is also a problem that it is necessary to align the two in order to align the two. Therefore, an object of the present invention is to solve the above-mentioned problems of the conventional linear encoder device and to provide a linear encoder device that does not require mechanical connection with a linear synchronous motor.

[0005]

SUMMARY OF THE INVENTION The present invention is a linear encoder device for detecting a moving state of a linear synchronous motor, which is integrally provided with a detecting portion for detecting a magnetic field generated by the linear synchronous motor on the linear synchronous motor side. By doing so, the above-mentioned object is achieved. The linear encoder device of the present invention is a device for detecting movement information such as a moving position and a moving speed of a linear synchronous motor or a moving body driven by the linear synchronous motor, and detects a magnetic field generated by the linear synchronous motor. By this, the movement information is obtained. The magnetic field generated by the linear synchronous motor changes along the moving direction of the linear synchronous motor. The linear encoder device of the present invention obtains movement information of the moving portion of the linear synchronous motor by detecting the change in the magnetic field.

In the linear encoder device of the present invention,
The detection unit can be installed at the end of the magnetic field generation unit of the movable unit of the linear synchronous motor with respect to the moving direction of the linear synchronous motor, whereby the magnetic field generation unit of the fixed unit of the linear synchronous motor can be installed. The main magnetic flux can be detected. Further, in the linear encoder device of the present invention, the detection unit can be installed on the side of the magnetic field generation unit of the movable unit of the linear synchronous motor with respect to the moving direction of the linear synchronous motor, thereby fixing the linear synchronous motor. It is possible to detect the leakage magnetic flux in the lateral direction of the magnetic field generation unit disposed in the section.

Further, in the linear encoder device of the present invention, the detecting portion can be provided in parallel with the magnetic field generating portion of the fixed portion of the linear synchronous motor, whereby the magnetic field of the movable portion of the linear synchronous motor can be detected. . Further, in the linear encoder device of the present invention, both ends of the magnetic path are opposed to magnetic poles at different positions of the magnetic field generation portion of the fixed portion of the linear synchronous motor, and magnetic path forming means disposed in the magnetic path. A magnetic detection means for detecting a magnetic field state can be provided in the detection section, whereby the main magnetic flux of the magnetic field generation section arranged in the fixed section of the linear synchronous motor can be detected.

[0008]

When the linear synchronous motor is driven, the magnetic field state on the fixed portion side with respect to the moving portion changes. The detector included in the linear encoder device of the present invention detects a change in the magnetic field of the linear synchronous motor. The change in the magnetic field of the linear synchronous motor corresponds to the movement information such as the position and speed of the moving portion in the linear synchronous motor, and the movement information of the linear synchronous motor can be obtained by the detection signal of the detecting portion. The detection unit installed at the end of the magnetic field generation unit of the movable unit of the linear synchronous motor with respect to the moving direction of the linear synchronous motor detects the main magnetic flux of the magnetic field generation unit arranged at the fixed unit of the linear synchronous motor. When the linear synchronous motor is driven, the movable part moves with respect to the fixed part. Due to this movement, the strength and direction of the magnetic field from the magnetic field generating unit on the fixed unit side change. The detection unit provided on the movable unit side can detect this magnetic field change as movement information of the linear synchronous motor. Further, the detection section provided on the side of the movable section detects the leakage magnetic flux of the magnetic field generation section arranged in the fixed section of the linear synchronous motor and detects the change due to the movement of the leakage magnetic flux, thereby The movement information of the synchronous motor can be detected.

Further, in the case of a construction in which a plurality of magnetic field detecting means are provided in parallel with the magnetic field generating section of the fixed section of the linear synchronous motor, the detecting section is located close to the movable section of the linear synchronous motor. A certain magnetic field detection means can detect the magnetic field of the movable part and obtain movement information of the movable part. Further, when using a magnetic detecting means arranged in the magnetic path to detect a magnetic field state in the magnetic path, both ends of the magnetic path face magnetic poles at different positions of the magnetic field generating portion of the fixed portion of the linear synchronous motor. Therefore, the strength and direction of the magnetic flux passing through the magnetic path changes as the moving unit moves. The movement information of the moving body can be detected by detecting the change of the magnetic flux in the magnetic path by the magnetic detection means.

[0010]

An embodiment of the present invention will be described in detail below with reference to the drawings. (First Embodiment of the Present Invention) First, a configuration example for implementing the encoder apparatus of the present invention will be described with reference to FIGS. 1 is a sectional view for explaining the configuration of a first embodiment of the linear encoder device of the present invention, and FIG. 2 is a perspective view for explaining the configuration of the first embodiment of the linear encoder device of the present invention.

In FIG. 1, a linear encoder device 1 is formed integrally with a linear synchronous motor 2. The linear synchronous motor 2 in the first embodiment includes a stator 23 and a mover 21 that moves relative to the stator 23. The stator 23 has a base formed by extending in the moving direction of the mover 21. It has a constituent yoke 24 and a permanent magnet 25 arranged on the yoke 24 along the movement direction. The permanent magnets 25 have different magnetic poles alternately arranged at a constant cycle. The mover 21 has a coil 22 and is movably provided by forming a gap 26 at a constant interval with the permanent magnet 25. In addition, this mover 21
A movable body such as the table 3 can be provided in the table.

On the other hand, the encoder device 1 of the present invention is provided with the detecting portion 11 provided on the mover 21 side. The mounting position of the detector 11 on the mover 21 is an end in the moving direction of the mover 21, and is installed by the mount 12 so as to face the permanent magnet 25 of the linear synchronous motor 2.
The magnetic field formed by 5 is detected. As the detection unit 11, for example, a magnetic detection unit such as a Hall element or a magnetoresistive element can be used. When the linear synchronous motor 2 is driven, the mover 21 moves with respect to the stator 23. This mover 2
With the movement of 1, the strength and direction of the magnetic field near the detection unit 11 change. The detection unit 11 detects the change in the magnetic field and outputs the movement information of the linear synchronous motor 2. Since the detector 11 is installed adjacent to the mover 21, it may be affected by the magnetic field of the coil 22 of the mover 21. The magnetic field change of the permanent magnet 25 can be effectively detected by setting the distance enough to ignore the influence of the magnetic field from the magnetic field, or by setting the installation direction of the magnetic detection means in the direction in which the influence of the magnetic field from the coil 22 is reduced. You can

(Second Embodiment of the Invention) A second embodiment of the linear encoder apparatus according to the present invention will be described below with reference to the perspective view of FIG. The second embodiment shown in FIG. 3 is different from the first embodiment only in the installation position of the detection unit 12, and is otherwise the same as the first embodiment. Therefore, only the detection unit 12 will be described below. The detection unit 12 is installed on the side of the mover 21 of the linear synchronous motor 2 and detects the leakage magnetic flux formed in the lateral direction of the permanent magnet 25 arranged on the stator 23 side of the linear synchronous motor 2. Is used to obtain the movement information of the linear synchronous motor.

(Third to Fifth Embodiments of the Present Invention) Next, the third to fifth embodiments of the present invention will be described with reference to FIGS.
An explanation will be given using (c). In the third to fifth embodiments, as the linear synchronous motor 2 constituting the linear encoder device of the present invention, a plurality of coils 27 are arranged on the stator side along the moving direction thereof, and the permanent magnet 26 is arranged on the mover side. And a plurality of detecting units 13 to 15 of the linear encoder device are arranged on the stator side of the linear synchronous motor.

In FIG. 4 (a), the detection unit 13 is constructed by installing it side by side along the coil 27 on the fixed unit side of the linear synchronous motor. Permanent magnet 26 on mover 21 side
The stator side coil 27 and the detection unit 13 are arranged to face each other, and the magnetic field state with respect to the coil 27 and the detection unit 13 changes as the mover 21 moves. The detection 13 can obtain the movement information of the mover 21 by detecting the change in the magnetic field.

The fourth embodiment of the present invention shown in FIG. 4B is to prevent the coil 27 from affecting the detection unit 14 in the linear encoder device having the configuration shown in FIG. The magnetic shield 41 is provided between the coil 27 and the detection unit 14 to more efficiently detect the magnetic field of the permanent magnet 26.

The fifth embodiment of the present invention shown in FIG. 4 (c) prevents the coil 27 from affecting the detection unit 14 in the linear encoder device having the configuration shown in FIG. 4 (a). Therefore, the detection unit 15 is installed at a position close to the permanent magnet 26, and the magnetic field of the permanent magnet 26 is detected more efficiently.

(Sixth Embodiment of the Present Invention) FIG. 5 is a sectional view for explaining a sixth embodiment of the linear encoder device of the present invention. The sixth embodiment shown in FIG.
6 is different, and other configurations are the same as those in the first
This is almost the same as the embodiment described above. Therefore, in the following, the detection unit 1
Only 6 will be described. Detection unit 16 of the sixth embodiment
Is composed of a magnetic detection means 42 and a magnetic path 43. The magnetic path 43 is a component formed in a substantially U shape by a magnetic material having a high permeability, and has a first magnetic path end 44 that is one end thereof and a first magnetic path end 44 that is the other end thereof. The two magnetic path ends 45 both face the permanent magnet 25 on the stator 23 side with a gap 26 in between. In addition, the first magnetic path end portion 44
The magnetic poles of the permanent magnets 25 facing each other and the magnetic poles facing of the second magnetic path end portion 45 are set to have different polarities.

Further, a magnetic detecting means 42 is installed in the middle of the magnetic path 43 to detect the strength and direction of the magnetic flux passing through the magnetic path. For example, when a Hall element is used as the magnetic detection means 42, the magnetic flux intensity and the magnetic flux direction can be detected. In FIG. 5, the magnetic detection means 42
Is the central portion of the magnetic path 43, but it can be located at any position within the magnetic path 43.

Next, the operation of the sixth embodiment of the present invention will be described with reference to FIG. Note that FIG. 7 schematically shows only the relationship between the permanent magnet on the stator side, the coil on the mover side, and the detection unit 16, the magnetic flux by the permanent magnet is shown by a solid line arrow, and the magnetic flux by the coil is shown by a broken line arrow. Shows. First, when the mover and the stator are in the positional relationship as shown in FIG. 7A, the first magnetic path end portion 44 faces the N pole of the permanent magnet and the second magnetic path end portion 45. Is a permanent magnet S
The coil facing the pole and facing the N pole of the permanent magnet is the S pole, and the coil facing the S pole is the N pole. At this time, the magnetic flux due to the permanent magnet and the magnetic flux due to the coil pass through the magnetic detection means 42 in the right direction in the drawing. Therefore, the magnetic detection means 42 detects a large magnetic field in the right direction in the figure.

Next, when the mover moves to the right in the figure, the polarity of the coil is reversed as shown in FIG. 7B, and the polarity of the coil facing the N pole of the permanent magnet is also reversed. It becomes the N pole, and the polarity of the coil facing the S pole also becomes the S pole. At this time, in the magnetism detecting means 42, the magnetic flux from the permanent magnet is in the right direction in the figure, while the magnetic flux from the coil is in the left direction in the figure. Therefore, the magnetic detection means 42 detects a small magnetic field strength corresponding to the difference between the magnetic flux of the permanent magnet and the magnetic flux of the coil. Further, when the mover moves to the right in the figure, the first magnetic path end portion 44 and the second magnetic path end portion 45, as shown in (c) of FIG. The position is opposite to the boundary with the pole.
At this time, in the magnetism detecting means 42, the magnetic flux due to the permanent magnet is almost eliminated, while the magnetic flux due to the coil is in the left direction in the figure. Therefore, the magnetic detection means 42 detects only the magnetic flux generated by the coil.

When the mover has the positional relationship shown in FIG. 7D, the first magnetic path end portion 44 faces the S pole of the permanent magnet and the second magnetic path end portion 45 faces the permanent magnet. The coil facing the N pole and facing the N pole of the permanent magnet is the S pole, and the coil facing the S pole is the N pole. At this time, the magnetic flux due to the permanent magnet and the magnetic flux due to the coil pass leftward in the drawing through the magnetic detecting means 42. Therefore, the magnetic detecting means 42 detects a large magnetic field in the left direction in the figure. When the mover slightly moves from the position shown in FIG. 7 (d), the first magnetic path end 44 is made of S of the permanent magnet as shown in FIG. 7 (e).
The second magnetic path end portion 45 is opposed to the pole and the polarity of the coil is reversed while the second magnetic path end portion 45 is opposed to the N pole of the permanent magnet, and the coil opposed to the N pole of the permanent magnet is the N pole and the coil opposed to the S pole. Is the south pole. At this time, in the magnetism detecting means 42, the magnetic flux from the permanent magnet is in the leftward direction in the figure, while the magnetic flux from the coil is in the rightward direction in the figure. Therefore, the magnetic detection means 42 detects a small magnetic field strength corresponding to the difference between the magnetic flux of the permanent magnet and the magnetic flux of the coil.

When the mover moves further to the right in the figure,
As shown in (f) of FIG. 7, the first magnetic path end portion 44 and the second magnetic path end portion 45 are at positions facing the boundary portion between the N pole and the S pole of the permanent magnet. At this time, in the magnetic detecting means 42, the magnetic flux due to the permanent magnet is almost eliminated, while the magnetic flux due to the coil is in the right direction in the figure. Therefore, the magnetic detection means 42 detects only the magnetic flux generated by the coil. After that, when the mover moves to the right in the figure,
The positional relationship shown in (a) of FIG.
Therefore, (f) of FIG. 7 is repeated. Therefore,
The strength and direction of the magnetic field detected by the detection unit will change as the linear synchronous motor moves, and the movement information of the linear synchronous motor can be obtained from the detection output of this detection unit.

(Seventh Embodiment of the Present Invention) FIG. 6 is a sectional view for explaining a seventh embodiment of the linear encoder device of the present invention. The seventh embodiment shown in FIG.
7 is different, and the other configurations are the same as those in the first
And is almost the same as the sixth embodiment. Therefore, only the detection unit 17 will be described below.

The detecting section 17 of the seventh embodiment has substantially the same structure as the detecting section 16 of the sixth embodiment, and is composed of a magnetic detecting means 42 and a magnetic path 43. The magnetic path 43 is a constituent element formed of a magnetic material having a high magnetic permeability in a substantially U-shape, and has one end of the first magnetic path end portion 46 and the other end portion thereof. The two magnetic path ends 47 both face the permanent magnet 25 on the stator 23 side with a gap 26 in between. Further, the magnetic poles of the permanent magnet 25 facing the first magnetic path end portion 46 and the facing magnetic poles of the second magnetic path end portion 47 are
The polarities are set so that they are different from each other, and they are installed at a distance that is not affected by the magnetic field of the coil. Further, in the middle of the magnetic path 43, the magnetic detecting means 42 is installed as in the sixth embodiment, and detects the strength and direction of the magnetic flux passing through the magnetic path. For example, when a Hall element is used as the magnetic detection means 42, the magnetic flux intensity and the magnetic flux direction can be detected. In FIG. 6, the magnetic detection means 42 is located at the center of the magnetic path 43, but it can be located at any position within the magnetic path 43.

Next, the operation of the seventh embodiment of the present invention will be described with reference to FIG. Note that FIG. 7 schematically shows only the relationship between the permanent magnet on the stator side, the coil on the mover side, and the detection unit 17, the magnetic flux by the permanent magnet is shown by a solid line arrow, and the magnetic flux by the coil is shown by a broken line arrow. Shows. First, when the mover and the stator have a positional relationship as shown in FIG. 8A, the first magnetic path end portion 46 faces the S pole of the permanent magnet and the second magnetic path end portion 47. Is the permanent magnet N
The coil facing the pole and facing the N pole of the permanent magnet is the S pole, and the coil facing the S pole is the N pole. At this time, the magnetic flux generated by the permanent magnets passes through the magnetic detection means 42 in the leftward direction in the drawing. Therefore, the magnetic detection means 42 detects the magnetic field in the left direction in the figure.

Next, when the mover moves to the right in the figure, the polarity of the coil is reversed as shown in FIG. 8B, and the polarity of the coil facing the N pole of the permanent magnet is also reversed. It becomes the N pole, and the polarity of the coil facing the S pole also becomes the S pole. At this time, in the magnetic detection means 42, the magnetic flux generated by the permanent magnet is in the leftward direction in the drawing. Therefore, the magnetic detection means 42
Will detect the magnetic field to the left in the figure. further,
When the mover moves to the right in the figure, (c) in FIG.
As shown in, the first magnetic path end portion 46 and the second magnetic path end portion 47
Is a position facing the boundary portion between the north pole and the south pole of the permanent magnet. At this time, in the magnetic detection means 42, the magnetic flux due to the permanent magnets is almost eliminated, and the output of the magnetic detection means 42 decreases.

When the mover has the positional relationship shown in FIG. 8 (d), the first magnetic path end portion 46 faces the N pole of the permanent magnet and the second magnetic path end portion 47 of the permanent magnet. The coil facing the S pole and facing the N pole of the permanent magnet is the S pole, and the coil facing the S pole is the N pole. At this time, the magnetic flux generated by the permanent magnets passes through the magnetic detection means 42 in the right direction in the drawing. Therefore, the magnetic detection means 42 detects the magnetic field in the right direction in the figure. When the mover slightly moves from the position of (d) in FIG. 8, the first magnetic path end portion 46 faces the N pole of the permanent magnet and the second magnetic path end portion faces as shown in (e) of FIG. 47
Indicates that the polarity of the coil is reversed while facing the S pole of the permanent magnet, and the coil facing the N pole of the permanent magnet is the N pole.
The coil facing the pole becomes the S pole. At this time, in the magnetic detection means 42, the magnetic flux due to the permanent magnets is in the right direction in the figure, and the magnetic detection means 42 detects the magnetic field due to the permanent magnets.

When the mover moves further to the right in the figure,
As shown in (f) of FIG. 8, the first magnetic path end portion 46 and the second magnetic path end portion 47 are positioned to face the boundary portion between the N pole and the S pole of the permanent magnet. At this time, in the magnetic detection means 42, the magnetic flux due to the permanent magnets is almost eliminated, and the output of the magnetic detection means 42 decreases. After that, when the mover moves to the right in the figure, the positional relationship shown in FIG.
The above-described steps (a) to (f) of FIG. 8 are repeated. Therefore, the strength and direction of the magnetic field detected by the detection unit changes with the movement of the linear synchronous motor, and the movement information of the linear synchronous motor can be obtained from the detection output of this detection unit.

(Eighth Embodiment of the Present Invention) FIG. 9 is a sectional view for explaining an eighth embodiment of the linear encoder device of the present invention. The eighth embodiment shown in FIG. 9 is a multi-pole type L
The linear encoder device of the present invention is applied to a DM linear synchronous motor. In the linear synchronous motor, a plurality of permanent magnets are divided and arranged in two side yokes 28,
The coil 2 is provided between the side yoke 28 and the center core 29.
2A and the coil 22B are moved.

The detecting section 18 of the linear encoder device of the present invention comprises a magnetic path 49 forming a magnetic path between the permanent magnets of both side yokes 28, and a magnetic detecting means 48 provided in the magnetic path 49. Contains. The magnetic path 43 is a component formed of a magnetic material having a high permeability, and one end of the first magnetic path and the other end of the second magnetic path are both side yokes. The magnetic poles of the permanent magnets facing the permanent magnets of No. 28 via the gap 26, and the first magnetic path ends of the permanent magnets, and the facing magnetic poles of the second magnetic path ends are:
The polarities are set to be different. A magnetic detecting means 48 is installed in the middle of the magnetic path 49, and the magnetic path 49
Detects the strength and direction of the magnetic flux passing through the inside. For example, when a Hall element is used as the magnetic detecting means 48, the magnetic flux intensity and the magnetic flux direction can be detected.
The magnetism detecting means 48 can be located at any position within the magnetic path 43.

Moving from (a) in FIG. 9 to the right in the figure, the magnetic field strength and polarity of the permanent magnets facing each end of the magnetic path change. The magnetic detection means 48 detects the change in the magnetic field, and the movement information of the linear synchronous motor can be obtained from the detection output of this detection section. In the case of this embodiment, the influence of the change in the magnetic field due to the coil can be reduced.

[0033]

As described above, according to the present invention,
It is possible to provide a linear encoder device that does not require a mechanical connection with a linear synchronous motor.

[Brief description of drawings]

FIG. 1 is a sectional view illustrating a configuration of a first embodiment of a linear encoder device of the present invention.

FIG. 2 is a perspective view illustrating the configuration of the first embodiment of the linear encoder device of the present invention.

FIG. 3 is a perspective view illustrating a configuration of a second embodiment of the linear encoder device of the present invention.

FIG. 4 is a perspective view illustrating a configuration of third to fifth embodiments of the linear encoder device of the present invention.

FIG. 5 is a sectional view for explaining a sixth embodiment of the linear encoder device of the present invention.

FIG. 6 is a sectional view for explaining a seventh embodiment of the linear encoder device of the present invention.

FIG. 7 is a schematic diagram for explaining the operation of the sixth embodiment of the linear encoder device of the present invention.

FIG. 8 is a schematic diagram for explaining the operation of the seventh embodiment of the linear encoder device of the present invention.

FIG. 9 is a sectional view for explaining an eighth embodiment of the linear encoder device of the present invention.

FIG. 10 is a diagram for explaining the configuration of a linear encoder device installed in a conventional linear synchronous motor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Linear encoder device 2 Linear synchronous motor 3 Table 11, 12, 13, 15, 16, 17, 17, 18 Detection part 21 Mover 22 Coil 23 Stator 24 Yoke 25 Permanent magnet 26 Gap 42,48 Magnetic detection means 43,49 Magnetic Path 44, 45, 46, 47 Magnetic path end

Claims (5)

[Claims] 1. A linear encoder device for detecting a moving state of a linear synchronous motor, wherein a detection unit for detecting a magnetic field generated by a permanent magnet of the linear synchronous motor is integrally provided on the linear synchronous motor side. And linear encoder device. 2. The linear encoder device according to claim 1, wherein the detection unit is installed at an end of a magnetic field generation unit of a movable unit of the linear synchronous motor with respect to a moving direction of the linear synchronous motor. 3. The linear encoder device according to claim 1, wherein the detection unit is installed on a side portion of a magnetic field generation unit of a movable unit of the linear synchronous motor with respect to a moving direction of the linear synchronous motor. 4. The linear encoder device according to claim 1, wherein the detection unit is provided together with a magnetic field generation unit of a fixed unit of the linear synchronous motor. 5. The magnetic path forming means, wherein both ends of the magnetic path of the detecting section face magnetic poles at different positions of the magnetic field generating section of the fixed section of the linear synchronous motor, and the magnetic path is disposed in the magnetic path. The linear encoder device according to claim 1, further comprising a magnetic detection unit that detects a magnetic field state.