JPS63167660A - Stopping device for linear motor - Google Patents

Abstract

PURPOSE:To stop a moving body at a predetermined stopping position with a simple construction by providing an attracting coil at the coil space of a stator core, and providing teeth at the same pitch as that of the teeth of the coil space at the body. CONSTITUTION:A linear motor has a flat platelike stator core 1 in which a stator coil 4 is wound, and moving body 12 which is arranged at a predetermined parallel gap on the core 1. Attracting coils 10, 11 are wound in the coil space 9 at least at one side end of the core 1 at the stopping positions of the body 12. Teeth 14 are formed at the same pitch as that of the teeth 2 of the space 9 in which the coils 10, 11 are wound. The corresponding position of the teeth 14 of the body 12 side to the teeth 2 of the space 9 of the core 1 is detected by a sensor, and a DC or a single-phase current is simultaneously applied to the coils 10, 11, thereby stopping the body 12 at an object position.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a non-contact stopping device for a linear motor.

[Prior Art] FIG. 8 is a schematic diagram of a conventional three-phase four-pole linear motor. In the figure, 1 is a flat stator core in which teeth 2 and coil grooves 3 are alternately provided at a constant pitch, 4 is a stator coil wound through the coil grooves 3 of the stator core 1,
Reference numeral 5 denotes a reaction plate disposed so as to maintain a constant parallel gap with the stator core 1, and is made of a conductive material such as an aluminum plate. Reference numeral 6 denotes a movable plate attached to the back surface of the reaction plate 5, which also serves as a back yoke that forms a magnetic circuit with the stator core 1. The reaction plate 5 and the movable plate 6 constitute a moving body 7. Spacers 8 are installed as dummy coils in each of the three coil grooves 3 to fill the coil spaces 9 formed at both ends of the stator core 1.

Next, the operation will be explained.

The stator cores 1 are arranged at predetermined intervals along a rail (not shown), and if a traveling magnetic field is generated in the stator coils 4 of the stator core 1, the rear crayon plate 5
An eddy current is generated inside, and the movable plate 6 receives thrust due to this eddy current and the magnetic flux of the magnetic field, and moves along the rail toward the destination.

In order to stop the moving body 7 at a predetermined position, reverse phase braking is applied by applying a current in the opposite direction to the stator coil 4 installed immediately before the stop position, and the speed is sufficiently reduced to near zero. energization to the stator coil 4 is stopped, the target position is detected by a sensor, and a mechanical brake is applied. Alternatively, it is brought into contact with a shock absorber or the like at an extremely low speed and then positioned using a ratchet or the like.

However, such stopping or positioning using mechanical brakes or contact makes the stopping mechanism complicated, resulting in problems such as wear, noise, and the fact that the moving body itself is affected by impact.

Therefore, in the past, for example,
As shown in No. 1, by providing a magnetic piece on the side of the moving body and separately providing an electromagnet at the stop position, the magnetic piece and electromagnet can be used to prevent the moving body from moving at a sufficiently low speed due to anti-phase braking as described above. It has been proposed to stop and position in a non-contact manner by applying a suction force between the two.

[Problems to be Solved by the Invention] However, in the stopping device described in the above-mentioned publication, an electromagnet is provided at the stopping position separately from the stator core and stator coil, so the structure becomes complicated and expensive. There was a problem with that. Further, since the position of the movable body cannot be corrected after it has stopped, precise positioning is difficult.

The present invention has been made to solve these problems, and the first object of the present invention is to provide a stopping device for a linear motor that utilizes the coil spacer portion of the stator core to perform the attraction action by an electromagnet. purpose.

A second object of the present invention is to make it possible to correct the stop position of a movable body, and a third purpose is to enable the positioning to be performed in steps.

[Means for Solving the Problems] In the linear motor stopping device according to the present invention, as a first means for achieving the above-mentioned first object, firstly, a flat stator having a stator coil wound thereon is used. In a linear motor having an iron core and a movable body disposed with a constant gap parallel to the stator core, the fixed and stator cores are arranged at at least one end at a stop position of the movable body. A suction coil is wound around the coil space of the movable body, and teeth are provided on the movable body at the same pitch as the teeth of the coil space around which the suction coil is wound. (referred to as an invention).

Next, as a second means to achieve the above second objective,
The suction coil in the first invention is wound around the coil space portions at both ends of the stator core, and the teeth provided on the movable body have the same pitch as the teeth of the coil space portions. One side is provided offset by a half pitch (hereinafter referred to as the second invention).

Further, as a third means for achieving the third object, a plurality of suction coils according to the first invention are wound around the coil space portions at both ends of the stator core, and the suction coils are moved. The teeth provided on the body include the same pitch tongue portion as the teeth of the coil space portion and a different portion (hereinafter referred to as the third invention).

[Function] In the first invention, when the movable body approaches the target position in a sufficiently decelerated state, a sensor or the like detects the corresponding positions of the teeth on the movable body side and the teeth in the coil space portion on the stator core side. If a direct current or single-phase current is applied to the attraction coil at the same time as the detection is performed, an electromagnetic path will be formed between the two teeth, and the moving body will stop accurately at the target position due to the attraction action of the electromagnet.

Next, in the second invention, since the teeth on the movable body side are shifted from the teeth in the coil space portion on the stator core side by a half pitch on one side, the movable body stops at the target position as described above. If the energization ratio to the attraction coil on the desired side is increased, the ends of the movable body in the same direction will move by half a pitch as a whole, thereby making it possible to correct the stopping position or to make final positioning.

Next, in the third invention, since the teeth on the movable body side include a pitch part that is partially different from the teeth in the coil space part on the stator core side, the different pitch part is, for example, 1, 5.
With pitch, the moving body can be moved in steps within the same range as the pitch of the teeth on the stator core side by switching and controlling the energization of multiple suction coils wound around the coil space. can.

[Example] Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic configuration diagram of a first embodiment of the present invention, and is related to the first invention. FIG. 2 is a view taken along line H-II in FIG. 1. Note that the same or equivalent parts as shown in FIG. 8 are denoted by the same reference numerals, and the explanation thereof will be omitted.

In this embodiment, suction coils 10.degree. 11 are provided in place of the spacers at both ends of the stator core 1 shown in FIG. Moreover, the movable plate 13 constituting the movable body 12 is provided with teeth 14 corresponding to the teeth 2 of the coil space portion 9 around which the attraction coil 10.11 is wound at the same pitch. For this reason, the reaction plate 15 has teeth 14.
An opening 16 is provided so as to fit thereinto.

Next, the operation will be explained.

When stopping the movable body 12 at a predetermined position, as in the past, a current in the opposite direction is applied to the stator coil 4 to apply anti-phase braking to sufficiently reduce the speed of the movable body 12 until the speed reaches zero. Nearby, the anti-phase braking is stopped and the moving object 12 is allowed to enter at an extremely low speed. Next, a sensor (not shown) or the like detects the position where the teeth 14 on the movable body side and the teeth 2 on the stator core side completely oppose each other, and at the same time, direct current or single-phase current is applied to the attraction coils 10 and/or 11. Apply. Then, an electromagnetic path is formed between the opposing teeth 14 and 2 as shown by the arrow in FIG. 1, and the attraction force by the electromagnet acts on the movable plate 13 to attract the movable body 12 and stop it accurately at the target position. urge

Note that, as is clear from the above description, the suction coils for stopping the movable body 12 do not necessarily have to be provided at both ends of the stator core 1, but may be provided on either side on the right side. In addition, as shown in the modified example of FIG.
It is also possible to use a rectangular plate having only the central portion without an opening into which the plate 4 is inserted.

Next, FIG. 4 is a sectional view showing a second embodiment of the invention of 'M2. In the case of this second embodiment, the teeth 14 are provided at both ends of the movable plate 13 at the same pitch as the teeth 2 of the stator core 1. They are set just a little apart.

Therefore, the stopping position of the moving body 12 is initially set near the center of the moving body 12 by applying the same current value to the attraction coils 10.11 at both ends of the stator core 1.
Next, by changing the energization ratio for the attraction coils 10, 11 on both sides, the movable body 12 as a whole moves by 0.5 pitches in the direction of the larger energization ratio. That is, for example, as shown in FIG. 4, when the current value of the left side attraction coil 10 is larger than that of the right side attraction coil 1, the teeth 14 and 2 on the left side are exactly opposite to each other. Therefore, the left end 17 of the movable body 12 and the left end 18 of the fixed iron core 1 can be aligned by moving 065 pitches to the left from the initial stop position, and conversely, the right side suction When the suction coil 11 is larger than the left suction coil 10, the right end 19 of the movable body 12 can be aligned with the right end 20 of the fixed iron core 1, as shown in FIG. The position of the movable body 12 can be corrected or determined after it has stopped.

Next, FIG. 6 is a schematic configuration diagram showing a third embodiment according to the third invention. In the case of this third embodiment, stator core 1
Two suction coils 10, 10a, 1 are provided at both ends of the
1. In addition to providing the pitch of the teeth 14 on both sides of the movable plate 13, it is formed to include a portion A in which the pitch of the teeth 14 is the same as that of the teeth 2, and a portion B in which the pitch is 1.5 times that of the teeth 2.

The effect is as shown in FIG. 7(a), if only the leftmost suction coil 10 is energized, the left end 17 of the moving body 12
can be made to coincide with the right end 18 of the stator core 1, and then, when energization is switched to the rightmost attraction coil 11,
As shown in FIG. 2B, the right end 19 of the movable body 12 can be aligned with the right end 20 of the stator core 1. Furthermore, if the energization is switched to the second attraction coil 10a on the left side from this state, the left end 17 of the moving body 12 will be 0°5 pitch from the left end 18 of the stator core 1, as shown in FIG. stand out. On the other hand, if the energization is switched from the attraction coil 10 in FIG. 7(a) to the second attraction coil lla on the right side, the right end 19 of the movable body 12 is connected to the stator core as shown in FIG. 7(d). It can be made to protrude by 0.5 pitch from the right end 20 of 1. Of course, the suction coils 10 and 1
7(a) and Cb')
It can be stopped at an intermediate position, and this position can be changed by changing the energization ratio to the attraction coils 10 and 11.

[Effects of the Invention] As described above, according to the first invention, a suction coil is provided using the coil space of the stator core, and teeth are provided on the movable body side at the same pitch as the teeth of the coil space. With this arrangement, the movable body can be accurately stopped at a predetermined stop position in a non-contact manner with an extremely simple configuration.

Next, in the second invention, since the teeth on the movable body side are shifted from the teeth on the coil space part by half a pitch on one side, the teeth on the side of the movable body are shifted by a half pitch on one side, so that after the movable body stops at the target position, the teeth on the side of the suction coil on the desired side are shifted. By increasing the energization ratio, the entire moving object can be moved half a pitch in the same direction,
Position correction or final positioning is possible.

In addition, in the third invention, since the teeth on the moving body side include a pitch portion that is partially different from the teeth in the coil space portion, energization to the plurality of suction coils respectively wound in the coil space portion can be switched. By controlling the movable body, it is possible to move the movable body in steps within the same range as the pitch of the teeth on the stator core side.

[Brief explanation of the drawing]

1 is a schematic configuration diagram of a first embodiment of the present invention, FIG. 2 is a view taken along the line ■-■ in FIG. 1, and FIG. 3 is a schematic configuration diagram showing a modification of the first embodiment. 4 is a schematic configuration diagram of the second embodiment of the present invention, FIG. 5 is an operational explanatory diagram of the second embodiment, FIG. 6 is a schematic configuration diagram of the third embodiment of the present invention, and FIG. 7 is a diagram of the third embodiment. FIG. 8, which is an explanatory diagram of the operation of the embodiment, is a schematic configuration diagram of a conventional example. 1... Stator core 2... Teeth 4... Stator coil 9... Coil space part 1
0.10a, 11. lla...Suction coil 12...
- Moving body 13... Movable plate 14... Teeth In the drawings, the same reference numerals indicate the same or equivalent parts. Agent Patent Attorney Souji Sasaki Figure 7

Claims (3)

[Claims] (1) A flat stator core around which a stator coil is wound,
In a linear motor having a movable body disposed with a constant gap parallel to the stator core, the stator core at a stop position of the movable body has a coil space portion at least on one end. A stopping device for a linear motor, characterized in that a suction coil is wound around the movable body, and teeth are provided on the movable body at the same pitch as teeth of a coil space portion around which the suction coil is wound. (2) A flat stator core around which a stator coil is wound;
In a linear motor having a moving body disposed with a constant gap parallel to the stator core, the stator core at the stop position of the moving body is attracted to the coil space portions at both ends. As well as winding the coil for
A stopping device for a linear motor, characterized in that the movable body is provided with teeth having the same pitch as the teeth of a coil space portion around which the suction coil is wound, but shifted by a half pitch on either side. (3) A flat stator core around which a stator coil is wound,
In a linear motor having a movable body disposed with a constant gap parallel to the stator core, the stator core at the stop position of the movable body is located in the coil space portions at both ends, respectively. The movable body is characterized by being formed by winding a plurality of suction coils, and provided with teeth in a format including a pitch portion that is the same as the teeth of a coil space portion around which the suction coils are wound, and a pitch portion that is different from the teeth of the coil space portion around which the suction coils are wound. A stopping device for linear motors.