JPH11155277A - Linear motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the of a linear motor by a method, wherein a primary core is contracted in an axial direction. SOLUTION: Slits 8 are formed in a core plate to form a comb-shaped core plate. Four core groups 5 composed of layered comb-shaped core plates are assembled in a circumferential direction, and coils 9 are respectively contained in a slits 8 form a primary core 1. Rings 14 which are made of a magnetic material, have circular grooves in their outer circumferences and have notches at respective one positions in their circumferential directions are fitted to the insides of teeth 13 arranged in the axial direction to have the widths of the teeth 13 equivalent to be set at small Drivs and, on the other hand, to have the tip widths of the teeth 13 equivalent to be set at large Drivs.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linear motor in which a primary core is a runner and a secondary conductor is a stator.

[0002]

2. Description of the Related Art A linear motor has a configuration in which a squirrel-cage electric motor is developed on a plane, and its structure is shown in FIG.

[0003] The linear motor is largely divided into a primary core 1 and a secondary conductor 2, and has a long secondary structure in which the secondary side is longer than the primary side. The secondary side serves as a stator, and the primary side serves as a traveling element, and an air gap 3 is formed therebetween.

As shown in FIG. 7, the primary side core 1 is formed by arranging, for example, four core groups 5 each having a laminated thin core plate 4 made of a magnetic material at equal intervals along a circle, and forming a ring shape. It is sandwiched between a pair of flanges 6 and connected with a plurality of through bolts and nuts. A wheel 12 is rotatably provided in the flange 6. The core plate 4 is formed in a comb shape having teeth 13 by providing a plurality of slits 8 along the length direction. A coil 9 surrounding the secondary-side conductor 2 is shown in the slit 8 (shown in FIGS. 8A and 8B).
Is accommodated.

On the other hand, the secondary-side conductor 2 is a round bar-shaped magnetic body 1.
0 is formed by covering the outer peripheral surface with a nonmagnetic conductor 11 having interference. The magnetic body 10 is formed of iron, and the non-magnetic conductor is formed of aluminum, copper, or the like.

Here, as shown in FIG. 9B, the width B of the slit 8 is set slightly larger than the width C of the coil 9. The width dimension A of the teeth 13 is set to a value such that the magnetic flux density passing through the teeth 13 becomes appropriate. Tooth 13
There is no problem if the magnetic flux density passing through the slit 13 is larger than the magnetic flux density passing through the slit 8 by 30 to 40%, and as shown in FIG. And the width D other than the tip may be a value smaller than A.

However, with this dimension setting, the coil 9 cannot be inserted into the slit 8 during assembly.
As shown in FIG. 9, the width A of the teeth 13 is set to be larger than the width D other than the tip of the teeth 13 in FIG.

[0008]

However, since the width of the teeth 13 is increased to A, not only the total length of the core plate and also the primary core becomes longer but also heavier, and the cost is high. It is a motor.

On the other hand, only the width of the tip of the tooth 13 is A
Suffices, and D other than A is sufficient for dimensions other than the tip.

Therefore, an object of the present invention is to provide a linear motor that solves the above problem.

[0011]

According to a first aspect of the present invention, there is provided a linear motor comprising a plurality of comb-shaped core plates formed by forming teeth by providing a plurality of slits. A core group is formed, and a plurality of core groups are arranged radially so that the slits are located on the inner side and connected to each other to form a primary side core, and a coil is placed in the slit, and a cylindrical magnetic material is formed. A linear motor in which a long secondary conductor formed by providing a non-magnetic conductor on the outer peripheral surface of the primary motor is movably inserted through a gap in a space surrounded by a core group in the primary core, For each tooth that occupies the same position in the axial direction of the primary core, a ring is fitted inside the tooth, and the ring is formed of a magnetic material and provided with a cutout at one location in the circumferential direction. The ring Wherein the magnetic flux density passing therethrough is set to an appropriate value, and a circumferential groove is formed on the outer peripheral surface of the ring for fitting the tips of the teeth. A collar is fitted inside the teeth of the primary side core, and the collar is formed of a non-magnetic material in a substantially cylindrical shape, and is formed of a magnetic material only outside a portion corresponding to the teeth, and a magnetic flux density passing through the magnetic material is reduced. A ring having an appropriate width is embedded in a nonmagnetic material, and a cutout is formed at one position in the circumferential direction of the collar.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on an embodiment shown in the drawings. In this embodiment, since a part of the conventional linear motor is improved, the same parts as those of the conventional linear motor are denoted by the same reference numerals, and the description thereof will be omitted. Only different parts will be described.

(A) Embodiment 1 FIG. 1 shows the configuration of a linear motor according to Embodiment 1 of the present invention. As shown in the figure, among the teeth 13 in the core group 5 arranged at equal intervals in the circumferential direction, rings 14 made of a magnetic material are fitted inside the teeth 13 occupying the same position in the axial direction. .

First, the dimensions of the main part of the core plate 4 in the core group 5 will be described. As shown in FIG. 2B, the width of the slit 8 is set to B as shown in FIG. 9A, and the width of the teeth 13 is set to D. That is, it is set to a value as small as possible for the width of the slit and the teeth.

Next, the structure of the ring 14 is shown in FIG. The width dimension of the ring 14 is set to the value E described above so that the magnetic flux density passing through the ring 14 becomes an appropriate value. The thickness G of the ring 14 is set to an appropriate size as a magnetic flux path. On the outer peripheral surface of the ring 14, a circumferential groove 14a for fitting the teeth 13 is formed. Circumferential groove 1
The width of 4a is set to D, which is substantially the same as the width of the teeth 13, and the depth is set to F. And ring 1
A cutout portion 14b is formed to prevent a current from flowing through 4 and facilitate the fitting into the teeth 13.

Next, the operation of the linear motor will be described. To assemble the primary core 1, the coils 9 are accommodated in the respective slits 8 when assembling four core groups 5. When the four core groups 5 have been assembled, the rings 14 are fitted inside the respective teeth 13. At the time of fitting, the ring 14 is put into the teeth 13 in a state where the outer diameter is reduced by applying pressure from the outside and the hand is released. Then, the ring 14 from which the external pressure has been removed is restored, and the teeth 13 fit into the circumferential grooves 14. Therefore, the ring 14 does not move off in the axial direction.

Since the ring 14 is made of a magnetic material and has a width E, the teeth 1
The width of the tip of No. 3 is equivalent to E, and there is no problem with the magnetic flux density passing through the tip of the tooth 13, which is an appropriate value.

(B) Embodiment 2 Next, Embodiment 2 of the linear motor according to the present invention is shown in FIG. In this embodiment, a plurality of rings are combined into one, since it is complicated and increases the number of assembling steps when a ring is fitted into each tooth arranged in the axial direction as in the first embodiment.

That is, as shown in FIG. 4, a sleeve 17 is fitted inside the teeth 13 of the core group 5 in the primary core 1. The structure of the sleeve 17 will be described below. First, the core group 5 will be described. As the core group 5, the core group shown in FIG. This core group 5
The pitch between the teeth 13 is P.

Next, the structure of the sleeve 17 will be described with reference to FIG. As shown in the figure, the non-magnetic member 16 is formed in a substantially cylindrical shape having substantially the same length as the length of the core group 5, and the ring 15 made of the magnetic material has the same pitch P as the pitch P of the teeth 13 in the core group 5. The ring 15 is disposed on the outer peripheral surface of the magnetic body 16.
Are embedded in the non-magnetic body 16.

The width of the ring 15 is also set to E as in the first embodiment. For the same purpose as in the first embodiment, the sleeve 17 is formed with a notch 17a that is long in the axial direction.

The operation of such a linear motor will be described. To assemble the primary core 1, four core groups 5 are assembled together with the coils 9, and then the sleeve 17 is inserted inside the teeth 13. Since the notch 17a is formed in the sleeve 17, the sleeve 17 can be inserted in a state where the tip of the tooth 13 and the outer peripheral surface of the sleeve 17 slide.
When the sleeve 17 is inserted, the ring 15 and the teeth 13 are set to correspond to each other. Since the force for opening the sleeve 17 in the radial direction is constantly applied to the teeth 13,
The sleeve 17 does not come off easily.

The portion of the ring 15 formed of a magnetic material in the sleeve 17 corresponds to the teeth 13 and has a width E, so that the width of the tip of the teeth 13 of the core plate 4 is E. The magnetic flux density passing through the tips of the teeth of the core plate 4 does not have any problem and is an appropriate value.

[0024]

As can be understood from the above description, according to the linear motors according to the first and second aspects, the width of the teeth of the core plate constituting the core group is made smaller than in the prior art, while the magnetic flux density is set to an appropriate value. Since the ring having the width dimension set to the following value is fitted inside each tooth, the total length of the primary core of the linear motor can be reduced by the reduced width of the tooth.

Further, the linear motor is reduced in weight by the shortened length of the core group, and the manufacturing cost is reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a main part of a linear motor according to a first embodiment of the present invention.

2 (a) is a left side view and FIG. 2 (b) is a front view of a core group according to a first embodiment of the linear motor according to the present invention.

3A and 3B relate to a ring of a linear motor according to a first embodiment of the present invention, wherein FIG. 3A is a front view, and FIG.
X sectional view.

FIG. 4 is a sectional view showing a main part of a linear motor according to a second embodiment of the present invention.

5A and 5B relate to a sleeve of a linear motor according to a second embodiment of the present invention, wherein FIG. 5A is a front view, and FIG.
-Y sectional drawing.

6A is a left side view and FIG. 6B is a front sectional view of a conventional linear motor.

FIG. 7 relates to a core group in a conventional linear motor,
(A) is a left side view, (b) is a front view.

FIG. 8 relates to a coil in a conventional linear motor,
(A) is a front view, (b) is a right side view.

FIG. 9 is an explanatory diagram showing a dimensional relationship between a core group and a coil.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Primary side core 2 ... Secondary side conductor 4 ... Core plate 5 ... Core group 8 ... Slit 9 ... Coil 10 ... Magnetic body 11 ... Non-magnetic conductor 13 ... Teeth 14, 15 ... Ring 14a ... Circumferential groove 14b, 17a ... Notch 16 ... Non-magnetic material 17 ... Sleeve

Claims (2)

[Claims] 1. A core group is formed by laminating a plurality of comb-shaped core plates having teeth formed by providing a plurality of slits, and a plurality of core groups are radially arranged such that the slits are located inside. The primary side core is formed by joining together and the coil is housed in the slit, and the long secondary side conductor formed by providing the non-magnetic conductor on the outer peripheral surface of the cylindrical magnetic body is connected to the primary side. A linear motor movably inserted through an air gap into a space surrounded by a core group in a side core, wherein a ring is fitted inside the teeth for each tooth occupying the same position in the axial direction of the primary core. The ring is formed of a magnetic material and provided with a notch at one location in the circumferential direction. The width of the ring is set to a value at which the magnetic flux density passing through the ring becomes an appropriate value. Fit the tip of the tooth Linear motor, characterized in that the formation of the circumferential groove of Mutame. 2. A core group is formed by stacking a plurality of comb-shaped core plates by forming teeth by forming a plurality of slits, and a plurality of core groups are radially arranged such that the slits are located inside. The primary side core is formed by joining together and the coil is housed in the slit, and the long secondary side conductor formed by providing the non-magnetic conductor on the outer peripheral surface of the cylindrical magnetic body is connected to the primary side. In a linear motor, which is movably inserted through an air gap into a space surrounded by a core group in a side core, a collar is fitted inside teeth of the primary side core, and the collar is made of a substantially cylindrical nonmagnetic material. And a ring of a width which is formed of a magnetic material only outside the portion corresponding to the teeth and has a proper magnetic flux density passing through the magnetic material is embedded in the non-magnetic material, and is formed around the circumference of the collar. One place in the direction Linear motor, characterized in that the formation of the notch.