JP5352802B2 - Trapezoidal magnet skew structure of cylindrical linear motor with core - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain compatibility of decrease in cogging torque and increase in torque due to a skew structure, by making each cylindrical magnet piece which is to be provided at the peripheral face of a longitudinal core, which is set as trapezoidal in plan view. <P>SOLUTION: The trapezoidal magnet skew structure of the cylindrical linear motor with a core is so constituted as to ensure compatibility between the decrease in cogging and the increase in torque, by making each cylindrical magnet piece (3), which is stuck to the peripheral face of a columnar longitudinal core (2), set as trapezoidal in plan view, thereby making it in the skew structure. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a trapezoidal magnet skew structure for a cylindrical linear motor with a core, and in particular, a longitudinal core in which a plurality of cylindrical magnet pieces having a trapezoidal shape in a plan view are stacked in a longitudinal direction in a cylindrical excitation coil. The present invention relates to a novel improvement for realizing cogging reduction and torque increase by a skew structure.

  No patent application has been made for this type of linear motor, such as a cylinder, that has been used in the past, so no patent literature is disclosed, but generally a coreless linear mover is mainly used as a machine tool and Since it was used in chip mounters and the like, the cogging phenomenon during linear movement was not a big problem.

However, in order to increase the thrust at the time of linear movement, it is necessary to provide a core on the fixed side or the movable side or both, which naturally causes a problem of cogging.
In the flat linear motor different from the cylindrical linear motor described above, cogging is reduced by providing a skew in the stator, but the first member (mover or stator) 1 shown in FIGS. In the case of FIG. 3, each magnet piece 3 adhered to the outer periphery of the longitudinal core 2 such as a disc is composed of a conventional NS magnet array that alternately changes the magnetization direction. In FIG. A configuration in which the magnetization direction is shifted by 90 degrees for each piece 3 is disclosed.

Conventionally, this type of cylindrical linear motor has been configured as described above, and thus has the following problems.
That is, since the shape of the side portion 3a of each magnet piece 3 is aligned in a direction orthogonal to the linear movement direction A of the first member 1, cogging torque, which is torque unevenness during linear movement, is generated and smooth linear movement is achieved. It was difficult to get movement.

The trapezoidal magnet skew structure of a cylindrical linear motor with a core according to the present invention has a large number of cylindrical magnet pieces attached to the outer peripheral surface of a cylindrical or cylindrical long core, and the cylindrical magnet pieces adjacent to each other are attached. A first member having a different magnetic direction by 90 degrees, a linear cylindrical second member disposed at an outer peripheral position of the first member, and an excitation coil provided on an inner surface of the second member. Each of the cylindrical magnet pieces has a trapezoidal shape when viewed in plan, and is provided on the longitudinal core in a state of being in contact with each other, and the first or second member is the first or second member. longitudinal direction in the trapezoidal magnet skew structure co cylindrical linear motor with a you so that to linear movement along, the side direction sides of the respective cylindrical magnet pieces other than the both end portions of said longitudinal core Is the axial direction of the longitudinal core The long side based on the trapezoid of each cylindrical magnet piece and the short side shorter than the long side are in a non-orthogonal direction and in the axial outer peripheral surface along the axial direction when viewed from the outer peripheral plane of the longitudinal core. a configuration are arranged alternately, also at both ends of said longitudinal core is provided shaft body in the longitudinal cores and integrally or separately, the shaft body outward from both ends of the second member It is the structure which protrudes.

Since the trapezoidal magnet skew structure of the cylindrical linear motor with core according to the present invention is configured as described above, the following effects can be obtained.
That is, a plurality of cylindrical magnet pieces are attached to the outer peripheral surface of a cylindrical or columnar longitudinal core, and the first member formed by making the magnetization directions of the cylindrical magnet pieces adjacent to each other different by 90 degrees; A linear cylindrical second member disposed at an outer peripheral position of the first member; and an exciting coil provided on an inner surface of the second member, wherein each cylindrical magnet piece has a flat overall shape. a trapezoidal look, and provided in the longitudinal cores in a state in contact with each other, the first or second member, core you so that to linear movement along the longitudinal direction of the first or second member in trapezoidal magnet skew structure biasing cylindrical linear motor, the side direction sides of the respective cylindrical magnet pieces other than the both end portions of said longitudinal core, a non-orthogonal direction to the axial direction of said longitudinal core Yes, as seen in the plane of the outer circumference of the longitudinal core By the said shorter short side than the long side and the long side based on the trapezoid of each tubular magnet pieces in the axial outer peripheral surface along the axial direction which are arranged alternately with each other, a large linear motor without cogging torque Can be obtained.
Further, shafts are provided at both ends of the longitudinal core integrally or separately from the longitudinal core, and the shaft body projects outward from both ends of the second member, whereby both ends of the first member are A driven body can be connected to either side.

It is sectional drawing which shows the trapezoid magnet skew structure of the cylindrical linear motor with a core by this invention. It is sectional drawing which shows the other form of FIG. It is a top view which shows the principal part of the conventional cylindrical linear motor with a core. It is sectional drawing which shows the other conventional structure of FIG.

  In the present invention, a longitudinal core in which a plurality of cylindrical magnet pieces having a trapezoidal shape in a plan view are disposed in a longitudinal direction in a cylindrical excitation coil, and cogging reduction and torque increase are both achieved by a skew structure. It is an object of the present invention to provide a trapezoidal magnet skew structure for a cored cylindrical linear motor.

A preferred embodiment of a trapezoidal magnet skew structure of a cored cylindrical linear motor according to the present invention will be described below with reference to the drawings.
Note that the same or equivalent parts as in the conventional example will be described using the same reference numerals.
In FIG. 1, what is indicated by reference numeral 1 is a first member having a magnetic longitudinal core 2 having a cylindrical or columnar shape, and a large number of cylindrical magnet pieces 3 are attached to the outer peripheral surface of the longitudinal core 2. Is provided.

Each cylindrical magnet piece 3 is constituted by a ring-shaped body having a trapezoidal shape in plan view, and each cylindrical magnet piece 3 is laminated along the longitudinal direction of the longitudinal core 2, that is, the axial direction. The side portion direction B of the three side portions 3a is formed so as to be in a non-orthogonal direction with respect to the axial direction of the longitudinal core 2, that is, the linear motion direction C, thereby forming a skew structure. .
That is, as shown in FIG. 1, the side direction B of the side portion 3 a of each cylindrical magnet piece 3 other than both end portions 1 a and 1 b of the longitudinal core 2 is relative to the axial direction C of the longitudinal core 2. From the long side 3A and the long side 3A based on the trapezoid of each cylindrical magnet piece 3 on the axial outer peripheral surface 2a along the axial direction C as viewed in the outer peripheral plane of the longitudinal core 2 Since the short short sides 3B are alternately arranged, the aforementioned skew structure is achieved.

A linear cylindrical second member 4 is disposed on the outer side of the first member 1, and a plurality of exciting coils 5 are disposed on the inner surface 4 a of the second member 4 according to the pole pitch X. Yes.
The magnetizing directions D of the cylindrical magnet pieces 3 are formed to be 90 degrees different from each other in the cylindrical magnet pieces 3 adjacent to each other. However, the configuration in which the magnetization direction D is changed by 90 degrees is well known as a means for improving torque, and a magnetic material can be used for the second member 4.

  In the cylindrical linear motor 10 with a core formed by combining the first member 1 and the second member 4 described above, both ends of the longitudinal core 2 protrude outward from both ends 4b and 4c of the second member 4. When the shaft body 11 is provided, a drive signal is supplied to the exciting coil 5 of the second member 4 as a stator, so that the first member 1 having the shaft body 11 serves as a mover in the linear motion direction C. Can move along the line.

Contrary to the linear motion described above, when a drive signal is supplied to the excitation coil 5 with the shaft 11 and the first member 1 fixed as a stator, the second member 4 becomes a mover. It can move along the linear movement direction C.
FIG. 2 shows another embodiment of FIG. 1 and shows a configuration in which the arrangement phase of each magnet piece 3 at the same pole pitch X is changed, but the other configuration is the same as FIG. Therefore, illustration and description are omitted.

  The trapezoidal magnet skew structure of the cored cylindrical linear motor according to the present invention can be applied not only to a torqueful linear motor with less cogging but also to a linear actuator.

1 First member (mover or stator)
1a, 1b both ends 2 Long core
2a Axial outer peripheral surface 3 Cylindrical magnet piece 3a Side
3A long side
3B Short side B Side direction C Linear motion direction (axial direction)
4 Second member (mover or stator)
5 Excitation coil 10 Core linear motor with core 11 Shaft body X Pole pitch

Claims (2)

A large number of cylindrical magnet pieces (3) are attached to the outer peripheral surface of a cylindrical or columnar longitudinal core (2), and the magnetization direction (D) of each cylindrical magnet piece (3) adjacent to each other is 90 degrees. A different first member (1), a linear cylindrical second member (4) disposed at an outer peripheral position of the first member (1), and an inner surface (4a) of the second member (4) Excitation coil (5) provided in),
Each cylindrical magnet piece (3) has a trapezoidal shape when viewed in plan and is provided on the longitudinal core (2) in a state of being in contact with each other, and the first or second member (1, 4). , in trapezoidal magnet skew structure of the first or core with cylindrical linear motor was so that to linear movement along the longitudinal direction of the second member (1, 4),
The side direction (B) of the side portion (3a) of each cylindrical magnet piece (3) other than both end portions (1a, 1b) of the longitudinal core (2) is the axial direction of the longitudinal core (2) ( C) is a non-orthogonal direction, and the cylindrical magnet pieces (3) of the cylindrical magnet pieces (3) on the axial outer peripheral surface (2a) along the axial direction (C) as seen in the outer peripheral plane of the longitudinal core (2). A trapezoidal magnet skew structure for a cylindrical linear motor with a core, wherein a long side (3A) based on a trapezoid and a short side (3B) shorter than the long side (3A) are alternately arranged.   A shaft body (11) is provided at both ends of the longitudinal core (2) integrally or separately from the longitudinal core (2), and the shaft body (11) is disposed at both ends (4b) of the second member (4). 4c), the trapezoidal magnet skew structure for a cylindrical linear motor with a core according to claim 1.

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