CN102204071A

CN102204071A - Stepping motor

Info

Publication number: CN102204071A
Application number: CN2009801438059A
Authority: CN
Inventors: 赤羽健彦; 月冈靖幸; 常田晴弘; 斋藤礼
Original assignee: Sankyo Seiki Manufacturing Co Ltd
Current assignee: Nidec Instruments Corp
Priority date: 2008-12-01
Filing date: 2009-11-16
Publication date: 2011-09-28
Also published as: WO2010064368A1

Abstract

Provided is a stepping motor which can obtain a large torque without increasing the external diameter. More specifically, the stepping motor (100) includes a plurality of stator sets (20) which are arranged in the direction of the motor axis line L, so that electrode teeth (215, 225, 265, 275) have an identical angle position between the stator sets (20). In a rotor (3), a rotor magnet (32) is formed by a plurality of magnet pieces (320) which are arranged in the direction of the motor axis line L. In the rotor magnet (32), the same magnetic pole is continuously formed over the entire motor axis line L direction.

Description

Stepping motor

Technical field

The present invention relates to a kind of stator that disposes a plurality of utmost point teeth annularly and stepping motor of rotor of comprising.

Background technology

Stepping motor comprises: have the rotor magnet that alternately forms the N utmost point and the S utmost point on the outer peripheral face and the rotor of rotating shaft; And with the stator of the tubular of the outer peripheral face subtend of rotor magnet, stator generally has the two-phase stator pack, this stator pack comprises: the stator core of disposing a plurality of utmost point teeth annularly; And the coil that is centered around the outer circumferential side of utmost point tooth.

In above-mentioned stepping motor, following structure has been proposed: by two groups of two-phase stator pack are configured on the motor axis direction, and the pitch of utmost point tooth in these two groups of stator pack is staggered, can carry out at a high speed and small transmission (with reference to patent documentation 1).

Patent documentation 1: Japanese patent laid-open 10-28359 communique

Summary of the invention

Invent technical problem to be solved

Like this, in stepping motor, have by a plurality of stator pack being set in shared rotating shaft and making the structure difference of stator pack, thereby can carry out advantages such as high-precision transmission.So in kludge, parts feeder, above-mentioned stepping motor can be with acting on the drive source that makes part correctly move to assigned position.

Yet the another side that stepping motor can carry out high-precision transmission is that its torque is less, therefore, for example with acting under the situation that makes the drive source that heavier part moves, has the outside dimension greatly such problem that becomes.

The present invention does in view of above-mentioned technical problem, and its purpose is to provide a kind of stepping motor that outside dimension just can obtain big torque that do not increase.

The technical scheme that the technical solution problem is adopted

For solving the problems of the technologies described above, in the present invention, stepping motor comprises: rotor, this rotor have at outer peripheral face along the rotor magnet and the rotating shaft that circumferentially alternately are formed with the N utmost point and the S utmost point; And with the stator of the tubular of the outer peripheral face subtend of described rotor magnet, it is characterized in that, described stator disposes a plurality of single-phase or heterogeneous stator pack on the motor axis direction, this stator pack has the stator core of disposing a plurality of utmost point teeth annularly and is centered around the coil of described utmost point tooth outer circumferential side, between described a plurality of stator pack, the angle position of described utmost point tooth is identical.

In the present invention, because a plurality of stator pack are disposed on the motor axis direction, and between a plurality of stator pack, make the angle position of utmost point tooth identical, therefore, can continue to guarantee that the speciality of stepping motor is higher transmission precision, and can obtain bigger torque.In addition, owing to adopt a plurality of stator pack are configured in structure on the motor axis direction, therefore, it is less that the outside dimension of stepping motor keeps.

In the present invention, comparatively it is desirable to, described stator pack comprises that the stator core of A phase and coil, the stator core of B phase and coil are as described stator core and described coil, under the situation that adopts said structure, between described a plurality of stator pack, A phase utmost point tooth angle position each other is identical, and B phase utmost point tooth angle position each other is identical.If adopt above-mentioned two phase structure, then this two phase structure is different with phase structure, and the vibration in the time of transmission being moved etc. suppresses lowlyer.

In the present invention, comparatively it is desirable to, between described a plurality of stator pack, described stator core and described coil have identical structure.If constitute like this, then can realize the shared of part, therefore, can realize the cost degradation of stepping motor.

In the present invention, comparatively it is desirable to, in belonging to the described coil of described a plurality of stator pack, corresponding to the connection that is one another in series of the coil of phase homophase.Under the situation of using a plurality of coils, when coil is connected in parallel with each other, may be unbalanced to the electric current generation of in coil, flowing, but when coil being one another in series connection, the electric current that flows in coil is equated.So, can eliminate the inhomogeneous of torque, thereby can keep the stable rotation performance.In addition, make electric current reach the magnetic saturation state with the situation of guaranteeing big torque under owing to can not produce deviation, therefore, have and can make the big such advantage of mobile electrorheological at the moving electric current of a plurality of coil midstreams.

In the present invention, comparatively it is desirable to, be provided with the terminal that is used for described coil power supply at the outer circumferential side of described stator pack, between described a plurality of stator pack, the position of described terminal is positioned at the equal angular position.If adopt said structure, then the electrical connection towards terminal is easy.In addition, when stator pack is disposed at identical angle position, can regulate the angle position of stator pack as benchmark with terminal or the terminal board that maintains terminal.

In the present invention, comparatively it is desirable to, a plurality of terminals that form in described a plurality of terminal group by soldering on the conductive pattern that is formed on the common substrate.If between a plurality of stator pack, the position of terminal is positioned at identical angle position, and all terminals are connected with shared substrate, therefore, is easy towards the electrical connection of terminal.

In addition, comparatively it is desirable to, the substrate that uses rigidity is as substrate, according to said structure, and can be by the offset that fixedly prevents stator pack of terminal and substrate.

In the present invention, comparatively it is desirable to, in described rotor magnet, same pole integrally forms on the motor axis direction continuously.According to said structure, the zone with the stator subtend in the rotor magnet is in the state that is magnetized.Therefore, magnetic efficiency is higher, so, be favourable for obtaining bigger torque.

When adopting said structure, above-mentioned rotor magnet is comparatively desirable by being configured in that a plurality of magnet sheets on the motor axis direction constitute.If adopt said structure, then only change the total length that the quantity of magnet sheet just can be regulated rotor magnet.So, can reduce the kind of the part that the rotor magnet that will prepare uses, thereby can reduce the cost of stepping motor.

In the present invention, comparatively it is desirable to, it is against each other that described a plurality of magnet sheets are configured to adjacent magnet sheet.If constitute like this, then can easily realize the structure that the part with the stator subtend all is magnetized.

In the present invention, also can adopt following structure: in described a plurality of magnet sheets, contain the different magnet sheet of length dimension on the motor axis direction.That is, comparatively it is desirable to, the magnet sheet that the pattern length size is different is so that the length dimension of rotor magnet meets the length dimension of stator.If constitute like this, then can reduce the kind of the part that the rotor magnet that will prepare uses, thereby can reduce the cost of stepping motor.

In the present invention, also can adopt following structure: the quantity of described magnet sheet is different with the group number of described stator pack.If constitute like this, even then the length dimension of stator is being set under the situation of arbitrary value, therefore the kind of the part that the rotor magnet that also can reduce to prepare is used, can reduce the cost of stepping motor.

In the present invention, comparatively it is desirable to, the outer circumferential side tegmentum of described stator covers, and is filled with resin between described lid and described stator.If adopt said structure, then, therefore, can improve thermal diffusivity owing to the heat that produces in the coil can be passed to lid via resin.So, even if under the situation of using a plurality of stator pack, also the temperature of stepping motor can be risen and suppress lowlyer, therefore, can improve the reliability of stepping motor.

In the present invention, comparatively it is desirable to, dispose dividing plate between the adjacent stator pack in described a plurality of stator pack, described dividing plate welds together with the stator core of clamping the stator pack of this dividing plate in both sides.According to said structure, even under situation about stator core directly can not be welded each other, also a plurality of stator pack can be linked.

In the present invention, comparatively it is desirable to, in arbitrary stator pack in described a plurality of stator pack, the outer peripheral edges of the side end on the motor axis direction are the right angle part or the approximate right angle part of stator core, the outer peripheral edges of the end side on the motor axis direction are the R part of stator core, the stator core that is positioned at a described side end is laser-welded to described dividing plate, and the stator core that is positioned at described end side is spoted weld described dividing plate.Make the part of stator core warpage form the R shape by punch process, under the situation that forms above-mentioned R shape, can carry out spot welding, but can not carry out laser welding.On the other hand, in the interior rear flank that coil etc. is disposed at stator core, can carry out laser welding, but can not carry out spot welding.So, if before constituting stator pack, dividing plate is spoted weld a side that forms the R shape, then two ends can form right angle part or approximate right angle part, therefore, in the inboard that coil etc. is disposed at stator core with after forming stator pack, when with adjacent stator pack when connected to each other, can with the right angle part of stator core or approximate right angle partly with the dividing plate laser welding together.

In the present invention, comparatively it is desirable to, dispose encoder, FEEDBACK CONTROL is carried out in the energising of described coil according to the testing result of described encoder in the end of described rotating shaft.

In the present invention, comparatively it is desirable to, have radiating component, this radiating component is provided with the inner peripheral surface that bends to the peripheral shape correspondingly-shaped of described stator, and the inner peripheral surface of described radiating component directly or across fin contacts with the peripheral part of described stator.If constitute like this, then the contact area of the peripheral part of stator and radiating component is bigger.So, the middle heats that produce such as stator can be dispelled the heat efficiently.Especially being used under the situation that stator has a plurality of single-phase or multi phase stator groups, be effective.In the stepping motor that adopts said structure, the quantity of stator pack is more, correspondingly just heating easily of stator, but according to the present invention, the heat that produces in the stator can be dispelled the heat efficiently, therefore, the temperature of stator can be reduced and suppress lowlyer.

In the present invention, comparatively it is desirable to, have a plurality of described radiating components, described a plurality of radiating components link across a plurality of described stator pack.If constitute like this, then stator is made of a plurality of stator pack, but this stator is in the state of being strengthened by a plurality of radiating components.So stator pack linking part each other can not come off.

In the present invention, comparatively it is desirable to, described radiating component has the area outer peripheral face bigger than the area of described inner peripheral surface.If constitute like this, then can improve the heat dispersion of radiating component, therefore, the heat that produces in the stator can be dispelled the heat efficiently, suppress lowlyer thereby the temperature of stator can be risen.

In the present invention, comparatively it is desirable to, described stator is cylindric, and the described inner peripheral surface of described radiating component is circular-arc recessed flexure plane, and the described outer peripheral face of described radiating component is prismatic.If constitute like this, then radiating component forms the area structure bigger than the area of inner peripheral surface of outer peripheral face, therefore, can improve the heat dispersion of radiating component.In addition, even stator is cylindric,, then can utilize the prismatic outer peripheral face of radiating component that stepping motor is installed on the motor apparatus if the outer peripheral face of radiating component is prismatic, therefore, has stepping motor towards advantage such as the installation of motor apparatus is easy.

In the present invention, comparatively it is desirable to, have the lid with the periphery covering of described stator, described radiating component is as the lid member that constitutes described lid.If constitute like this,, also can realize structure with the periphery of covering covering stator even if then do not use the special-purpose part of lid.

In the present invention, comparatively it is desirable to, be provided with at the outer peripheral face of described stator and be used for substrate that described stator is powered, described substrate is in the state that exposes from described radiating component.If constitute like this, can prevent that then distribution, terminal on the substrate is because of the radiating component short circuit.

In the present invention, comparatively it is desirable to, described radiating component is an aluminum.If the radiating component of aluminum, then because pyroconductivity is higher, therefore, radiating effect is better, and low price.

In the present invention, comparatively it is desirable to, described radiating component is across the linking part of the outer peripheral face of the adjacent a plurality of described stator pack described stator pack adjacent with this.If constitute like this, then, therefore, can prevent that linking part from coming off or bending because radiating component plays the effect as the stiffener of the linking part of adjacent stator pack.

The invention effect

Description of drawings

Fig. 1 is to use the outside drawing of stepping motor of the present invention.

Fig. 2 is the key diagram of stator of using in the stepping motor shown in Figure 1 etc.

Fig. 3 is an exploded perspective view of observing stepping motor shown in Figure 1 from oblique upper.

Fig. 4 is the exploded perspective view from oblique beneath stepping motor shown in Figure 1.

Fig. 5 is the key diagram of the substrate that uses in the stepping motor shown in Figure 1.

Fig. 6 is the key diagram of the stator pack used in the stator shown in Figure 3.

Fig. 7 is the key diagram of the rotor that uses in the stepping motor shown in Figure 1.

Fig. 8 is the key diagram of the encoder that forms in the stepping motor shown in Figure 1.

Fig. 9 is the encoder housing used in the encoder of stepping motor shown in Figure 1 and the key diagram of sensor base plate.

Figure 10 (a) is the chart of variations in temperature of the each several part of expression stepping motor shown in Figure 1, and Figure 10 (b) is the chart of variations in temperature of each several part of the stepping motor of expression reference example.

Figure 11 is the key diagram that the improvement example of the radiating component that uses in the stepping motor of the present invention is used in expression.

Figure 12 is the key diagram that other radiating components that use in the stepping motor of the present invention are used in expression.

Figure 13 is the key diagram that the variation of the radiating component that uses in the stepping motor of the present invention is used in expression.

(symbol description)

2 stators

3 rotors

5 dividing plates

6 resins

7 substrates

8 encoders

9 lids

20 stator pack

21 A phase external stator iron cores

22 A phase internal stator iron cores

24 A phase coils

26 B phase external stator iron cores

27 B phase internal stator iron cores

29 B phase coils

31 rotating shafts

32 rotor magnets

80 encoder housing

81 encoder magnets

82 MR transducers (Magnetic Sensor)

85 sensor base plates

The through hole of 85e sensor base plate

91 first lid members (radiating component)

92 second lid members (radiating component)

93, the inner peripheral surface of 98a radiating component

98 radiating components

100 stepping motors

The peripheral part of 200 stators

215,225 A phase utmost point teeth

265,275 B phase utmost point teeth

320 magnet sheets

The L motor axis

Embodiment

With reference to accompanying drawing embodiments of the present invention are described.

(overall structure of stepping motor)

Fig. 1 is to use the outside drawing of stepping motor of the present invention, and Fig. 1 (a) is the stereogram that disposes the upper portion of connector in the stepping motor, and Fig. 1 (b) is the stereogram that disposes the lower portion of connector in the stepping motor.Fig. 2 is the key diagram of the stator that uses in stepping motor shown in Figure 1 etc., and Fig. 2 (a) is the longitudinal section of stepping motor shown in Figure 1, and Fig. 2 (b) is the cutaway view that the part of stator is amplified expression.Fig. 3 is an exploded perspective view of observing stepping motor shown in Figure 1 from oblique upper, and Fig. 4 is the exploded perspective view from oblique beneath stepping motor shown in Figure 1.

As shown in Figures 1 and 2, in the stepping motor 100 of present embodiment, constitute and cover 9 by the first lid member 91 and the second lid member 92 of long side direction towards motor axis L direction.In lid 9, be connected with flange 50 in the end of outlet side L1, from the rotating shaft 31 of above-mentioned flange 50 outstanding rotors 3.Leading section in rotating shaft 31 is connected with pinion 39.

In lid 9, from the end that the end face of anti-outlet side L2 is given prominence to substrate 7, also the end position adjacent at anti-outlet side L2 and aforesaid substrate 7 is provided with connector 77.

As Fig. 2, Fig. 3 and shown in Figure 4, stepping motor 100 has rotor 3 and stator 2 in the inboard of lid 9, and wherein, above-mentioned rotor 3 comprises: the rotor magnet 32 that circumferentially alternately is formed with the N utmost point and the S utmost point in the outer peripheral face upper edge; And rotating shaft 31, said stator 2 is tubular, with the outer peripheral face subtend of rotor magnet 32.

The end of the outlet side L1 of rotating shaft 31 and the end of anti-outlet side L2 are supported to and can rotate by bearing.In the present embodiment, bearing 57,59 supportings that each end of rotating shaft 31 is made of ball bearing are connected with the inner ring of bearing 57 in the end of the outlet side L1 of rotating shaft 31, and flange 50 is fixed in across bearing keeper 56 in the outer ring of bearing 57.In addition, be connected with the inner ring of bearing 59 in the end of the anti-outlet side L2 of rotating shaft 31, the outer ring of bearing 59 is fixing by bearing keeper 58.

(structure of stator 2)

Fig. 6 is the key diagram of the stator pack used in Fig. 3 and stator shown in Figure 4, and Fig. 6 (a) is the stereogram of a stator pack, and Fig. 6 (B) is its exploded perspective view.

In the stepping motor 100 of present embodiment, stator 2 is that a plurality of stator pack shown in Figure 6 20 are arranged in a rotating shaft 31 and form on motor axis L direction.

As shown in Figure 6, stator pack 20 forms A phase external stator iron core 21, is wound in A phase coil 24, A phase internal stator iron core 22, B phase internal stator iron core 27, the B phase coil 29 that is wound in bobbin 28, B phase external stator iron core 26 overlapping two phase structure on motor axis L direction of bobbin 23.

A phase external stator iron core 21 is from the outer peripheral edges of base plate 211 and extends the bottom tube-like that has of cylindrical portion 212 towards anti-outlet side L2, and erectting towards anti-outlet side L2 at the edge of the centre bore of base plate 211 has a plurality of utmost point teeth 215.A phase internal stator iron core 22 has circular flange part 221, and erectting towards outlet side L1 at the edge of the centre bore of this flange part 221 has a plurality of utmost point teeth 225.Therefore, when making A phase external stator iron core 21, bobbin 23 and A phase internal stator iron core 22 overlapping with when the bobbin 23 that is wound with A phase coil 24 is clamped in the both sides of motor axis L direction, constitute following structure: at the inner peripheral surface of bobbin 23, the utmost point tooth 215 that is formed at A phase external stator iron core 21 be formed at A mutually the utmost point tooth 225 of internal stator iron core 22 alternately be arranged in ring-type, at the outer circumferential side of above-mentioned utmost point tooth 215,225 around A phase coil 24 is arranged.

B phase external stator iron core 26 has circular flange part 261, and erectting towards outlet side L1 at the edge of the centre bore of this flange part 261 has a plurality of utmost point teeth 265.B phase internal stator iron core 27 has circular flange part 271, and erectting towards anti-outlet side L2 at the edge of the centre bore of this flange part 271 has a plurality of utmost point teeth 275.Therefore, when making B phase external stator iron core 26, bobbin 28 and B phase internal stator iron core 27 overlapping with when the bobbin 28 that is wound with B phase coil 29 is clamped in the both sides of motor axis L direction, constitute following structure: at the inner peripheral surface of bobbin 28, be formed on the B phase external stator iron core 26 utmost point tooth 265 be formed at B mutually the utmost point tooth 275 of internal stator iron core 27 alternately be arranged in ring-type, at the outer circumferential side of above-mentioned utmost point tooth 265,275 around B phase coil 29 is arranged.

At this, when the external stator iron core 21 that makes the A phase, the A phase coil 24 that is wound in bobbin 23, A phase internal stator iron core 22, B phase internal stator iron core 27, the B phase coil 29 that is wound in bobbin 28, B phase external stator iron core 26 are overlapping on motor axis L direction, the cylindrical portion 212 of A phase external stator iron core 21 is in the state that outer circumferential side covers A phase coil 24, A phase internal stator iron core 22, B phase internal stator iron core 27, B phase coil 29, and the flange part 261 of B phase external stator iron core 26 is in the state that embeds above-mentioned cylindrical portion 212 leading sections.

Under this state, the outer peripheral edges of the end of the anti-outlet side L2 of the motor axis L direction of stator pack 20 are the leading sections of the cylindrical portion 212 of A phase external stator iron core 21, at right angles shape (right angle part) or approximate right angle shape (approximate right angle part).Relative therewith, the outer peripheral edges of the end of the outlet side L1 of the motor axis L direction of stator pack 20 are the part that cylindrical portion 212 is erect from base plate 211 in A phase external stator iron core 21, are R shape (rounding part).Therefore, in the present embodiment, in order to link adjacent stator pack 20, specifically as described later, the dividing plate 5 that magnetic sheet is constituted is spot welded to the base plate 211 that outer peripheral edges are the A phase external stator iron core 21 of R shape.In addition, be laser-welded to the leading section of the cylindrical portion 212 of A phase external stator iron core 21 with being welded to dividing plate 5 on the A phase external stator iron core 21 of adjacent stator pack 20.

In the stator pack 20 that constitutes like this, be formed with terminal board 231 at a place that makes progress in week of the bobbin 23 that is wound with A phase coil 24, on above-mentioned terminal board 231, be connected with two butt 246.In addition, be wound with the end of A phase coil 24 respectively on two butt 246, terminal 246 is electrically connected by soldering with the end of coil 24.In addition, in the bobbin 28 that is wound with B phase coil 29, also be formed with terminal board 281, on above-mentioned terminal board 281, be connected with two butt 296 at a place that makes progress in its week.In addition, be wound with the end of B phase coil 29 respectively on two butt 296, terminal 296 is electrically connected by soldering with the end of coil 29.

At this, corresponding to two butt 246 of A phase with the direction of motor axis L direction quadrature on side by side, corresponding to two butt 296 of B phase also with the direction of motor axis L direction quadrature on side by side.And, owing to be set to identical with angle position around motor axis L corresponding to two butt 296 of B phase corresponding to two butts of A phase 246, therefore, corresponding to two butts of A phase son 246 with overlapping on motor axis L direction respectively corresponding to B two butt 296 mutually.

Above-mentioned terminal 246,296 and terminal board 231,281 are outstanding towards the radial direction outside from the breach 218 of A phase external stator iron core 21.The inner surface of terminal board 231,281 and the outer peripheral face butt of cylindrical portion 212.In addition, the inner edge butt in the both sides subtend that makes progress in week of the both ends that make progress in week of terminal board 231,281 and breach 218, thus stipulated all positions that makes progress.So, be that benchmark comes the result of the angle position of regulation terminal board 231,281 to be with the breach 218 of A phase external stator iron core 21, also stipulated the angle position of terminal 246,296.

In addition, be formed at A phase internal stator iron core 22 outer peripheral edges kick 228, be formed at the kick 268 of B phase external stator 26 outer peripheral edges unshakable in one's determination and be formed at the kick 278 of B phase internal stator iron core 27 outer peripheral edges and the inner edge butt in the both sides subtend that makes progress in week of breach 218, thereby stipulated the position that makes progress in week.Therefore, be that benchmark has been stipulated the angle position of A to internal stator iron core 22, B phase external stator unshakable in one's determination 26 and B phase internal stator iron core 27 with breach 218,

When using the stator pack 20 that constitutes like this to constitute stator 2, in the present embodiment, a plurality of stator pack 20 of same structure are configured to coaxial shape on motor axis L direction.Promptly, no matter in which stator pack 20, A phase external stator iron core 21 each other, the A phase coil 24 that is wound in bobbin 23 each other, A phase internal stator iron core 22 each other, B phase internal stator iron core 27 each other, the B phase coil 29 that is wound in bobbin 28 reaches B phase external stator iron core 26 each other and all has identical structure each other.In the present embodiment, five stator pack 20 are configured to coaxial shape on motor axis L direction.

In addition, no matter in which stator pack 20, the angle position of utmost point tooth all is identical.Promptly, shown in Fig. 2 (b), no matter in which stator pack 20, when the regulation position that makes progress with week during as benchmark, the utmost point tooth 215 that is formed at A phase external stator iron core 21 all is positioned at identical angle position each other, the utmost point tooth 225 that is formed at A phase internal stator iron core 22 all is positioned at identical angle position each other, and the utmost point tooth 265 that is formed at B phase external stator iron core 26 all is positioned at identical angle position each other, and the utmost point tooth 275 that is formed at B phase internal stator iron core 27 all is positioned at identical angle position each other.Therefore, the breakdown torque position consistency that between each stator pack 20 and rotor 3, produces, so, can obtain bigger torque.Especially, in the present embodiment,, therefore, can obtain bigger torque reliably owing to can prevent the deviation of the angle position of utmost point tooth between each stator pack 20.

(structure of substrate)

Fig. 5 is the key diagram of the substrate that uses in the stepping motor shown in Figure 1.In Fig. 5,

dot coil

24,29.

In the present embodiment, no matter in which stator pack 20, the angle position of terminal board 231,281 and terminal 246,296 all is identical.Therefore, in the stator 2 that disposes five stator pack 20, add up to 20 butt, but per 10 one row of these terminals, with motor axis L abreast linear array become two row.

Therefore, in the present embodiment, as shown in Figure 5, use to amount to 20 terminal hole 70 per 10 one row, linear array and become two substrates 7 that are listed as, make terminal 246,296 run through these terminal holes 70 and carry out soldering.At this, substrate 7 is PCB substrate, glass-such rigid substrates such as epoxy substrate.

In aforesaid substrate 7, be formed with Wiring pattern 71, the weld part that this Wiring pattern 71 has soldering a terminal 246 that is connected with an end of A phase coil 24 has the weld part of the terminal 246 that is connected with the other end of A phase coil 24 to be connected to each other with the soldering of adjacent stator pack 20, thereby A phase coil 24 in series is electrically connected.In addition, also be formed with Wiring pattern 72, the weld part that this Wiring pattern 72 has soldering a terminal 296 that is connected with an end of B phase coil 29 has the weld part of the terminal 296 that is connected with the other end of B phase coil 29 to be connected to each other with the soldering of adjacent stator pack 20, thereby B phase coil 29 in series is electrically connected.From soldering have with a plurality of stator pack 20 be positioned at the terminal 246 that the other end of A phase coil 24 of the stator pack 20 of an end is connected weld part extend distribution 73, have the weld part of the terminal 296 that is connected with the other end of B phase coil 29 to extend distribution 74 from soldering.In addition, from soldering have with a plurality of stator pack 20 be positioned at the terminal 246 that the end of A phase coil 24 of the stator pack 20 of the other end is connected weld part extend distribution 76, have the weld part of the terminal 296 that is connected with an end of B phase coil 29 to extend distribution 75 from soldering.

(structure of rotor)

Fig. 7 is the key diagram of the rotor 3 that uses in the stepping motor 100 shown in Figure 1.As Fig. 2 (a) and shown in Figure 7, in the stepping motor 100 of present embodiment, around the rotating shaft 31 of rotor 3, be connected with the rotor magnet 32 that constitutes by permanent magnet cylindraceous, outer peripheral face upper edge at above-mentioned rotor magnet 32 circumferentially alternately is formed with the N utmost point and the S utmost point, in addition, in rotor magnet 32, on motor axis L direction, integrally form identical magnetic pole continuously.Therefore, in rotor 3, rotor magnet 32 is arranged in the four corner at stator 2 places on the motor axis L direction.

When constituting above-mentioned rotor magnet 32, in the present embodiment, dispose a plurality of magnet sheets 320 cylindraceous along motor axis L direction around rotating shaft 31, in the present embodiment, a plurality of magnet sheets 320 dispose in adjacent magnet sheet 320 modes against each other.

At this, comprise the different magnet sheet 320 of length dimension on the motor axis L direction in a plurality of magnet sheets 320.In addition, in the present embodiment, stator pack 20 is 5 groups, but magnet sheet 320 is 7, and the quantity of magnet sheet 320 is different with the group number of stator pack 20.

Like this, in the present embodiment, do not use the long rotor magnet 32 consistent with the length dimension of stator 2, but prepare the different magnet material cylindraceous of length dimension, when the length of stator 2 was determined, the magnet material of configuration specified quantity was to magnetize.At this moment, can not constitute at the magnet material that only disposes same size under the situation of rotor magnet 32 of the length dimension that meets stator 2, the magnet material of a part is replaced with the different magnet material of length, to meet the length dimension of rotor magnet 32.So, also exist by the identical magnet sheet 320 of length dimension to constitute the situation of rotor magnet 32, but also exist present embodiment such constitute the situation of rotor magnet 32 by the different magnet sheet 320 of length dimension.In addition, also exist by the magnet sheet 320 of counting equal number with the group of stator pack 20 to constitute the situation of rotor magnet 32, but also exist the such magnet sheet 320 of present embodiment to constitute the situation of rotor magnet 32 by counting varying number with the group of stator pack 20.

If constitute like this, then can reduce the kind of the part of rotor magnet 32 usefulness that will prepare, thereby can reduce the cost of stepping motor 100.In addition, under the situation of using extremely long rotor magnet 32, when being shaped, become elongated owing to pass the mould of internal diameter, therefore, it is difficult to be shaped, and the easy in the longitudinal direction deviation of internal diameter size, but as present embodiment, if utilize a plurality of magnet sheets 320 to constitute rotor magnet 32, then internal diameter size can stablizing at length direction on the whole.Therefore, the gap size between stator 2 and the rotor magnet 32 is diminished, so, be favourable for obtaining bigger torque.

(structure of the structure/radiating component of lid 9)

In the stepping motor 100 of present embodiment, Fig. 1, Fig. 3 and the first lid member 91 shown in Figure 4 and the second lid member 92 by the higher metal of pyroconductivity for example aluminium constitute.Be not limited to aluminium, also can adopt copper etc., also be not limited to metal.In addition, the first lid member 91 and the second lid member 92 have the structure of following explanation, constitute towards the outside radiating component that dispels the heat of motor as the heat that will produce in stator 2.The first lid member 91 and the second lid member 92 are symmetrical, and its basic structure is identical.So, be that the center describes with the structure of the first lid member 91.

In the stepping motor 100 of present embodiment, stator 2 is cylindric, corresponding with the peripheral shape of said stator 2, form the circular-arc recessed flexure plane that has with the roughly the same curvature of curvature of the peripheral part 200 of stator 2 towards the inner peripheral surface 93 of stator 2 one sides in the plate-like body portion 96 of the first lid member 91.Size on the axis direction of size and stator 2 on the axis direction of the first lid member 91 about equally, first inner peripheral surface 93 that covers member 91 directly contacts with the peripheral part 200 of stator 2 on the whole the axis direction of stator 2.

In the first lid member 91, the bottom of plate-like body portion 96 from outboard end towards below be extruded with heat radiation board 95, the first lid members 91 outer peripheral face 94 be prismatic.In addition, the outer peripheral face 94 of the first lid member 91 is made of the outer surface 941 of plate-like body portion 96, the upper surface 942 of plate-like body portion 96, the lower surface 943 of heat radiation board 95, the inner surface 944 of heat radiation board 95 and the lower surface 945 of plate-like body portion 96, and the area of outer peripheral face 94 is bigger than the area of inner peripheral surface 93.On the heat radiation board 95 of the first lid member 91, two places that separate on axis direction are formed with the hole 97 that screw 99 is fixed.The second lid member 92 has and the identical structure of the first lid member 91.

Utilizing above-mentioned

first lid member

91 and 92 formation of the second lid member to cover at 9 o'clock, it is overlapping to make the first lid member 91 and second cover member 92 in the both sides of stator 2 in the mode that clips stator 2, then, will be fixed in hole 97 by the clamp structure 99 that screw, bolt etc. constitutes.Under this state, the bottom of the first lid member 91 and the second lid member 92 is closer to each other, and on the other hand, the upper end of the first lid member 91 and the second lid member 92 is also approaching each other.Consequently, the inner peripheral surface 93 of the first lid member 91 and the second lid member 92 directly contacts with the peripheral part 200 of stator 2.In addition, stator 2 is made of a plurality of stator pack 20, is in the state that a plurality of stator pack 20 is clipped in the middle and links but the first lid member 91 and second covers member 92.Therefore, stator 2 is in by the state of the

first lid member

91 and 92 reinforcements of the second lid member.

In addition, the first lid member 91 and the second lid member 92 are all across adjacent stator pack 20 linking part each other.That is, shown in Fig. 2 (b), the outer peripheral face of the outer peripheral face of A phase external stator iron core 21, B phase external stator iron core 26 directly contacts with the outer peripheral face that is present in adjacent stator pack 20 dividing plate 5 that is made of magnetic sheet each other with continuum of states.Therefore, adjacent stator pack 20 linking part each other is in the state than the easy bending of other parts, but, therefore, can prevent that linking part from coming off or bending because the first lid member 91 and the second lid member 92 play the effect as the stiffener of the linking part of adjacent stator pack 20.

Forming like this under 9 the state of cover, the bottom of the first lid member 91 and the second lid member 92 is closer to each other, on the other hand, and near the upper end arrival substrate 7 of the first lid member 91 and the second lid member 92.Therefore, substrate 7 is between the upper end that the first lid member 91 and second covers member 92 from covering 9 states that expose.Therefore, the distribution on the substrate 7, terminal can be because of the

first lid member

91 and 92 short circuits of the second lid member.

(structure of encoder 8)

Fig. 8 is the key diagram of formed encoder in the stepping motor 100 shown in Figure 1, Fig. 8 (a) is the stereogram of encoder housing of observing the end of the anti-outlet side of being located at stepping motor 100 from anti-outlet side, Fig. 8 (b) is that expression has been unloaded the exploded perspective view of the situation of sensor base plate from encoder housing, and Fig. 8 (c) is the key diagram of real estate of the outlet side of expression sensor base plate.Fig. 9 is the encoder housing used in the encoder of stepping motor 100 shown in Figure 1 and the key diagram of sensor base plate, and Fig. 9 (a) is a key diagram of observing encoder housing from anti-outlet side, and Fig. 9 (b) is a key diagram of observing sensor base plate from anti-outlet side.

Shown in Fig. 2 (a), in the stepping motor 100 of present embodiment, be formed with encoder 8 in the end of the anti-outlet side L2 of rotating shaft 31.In the present embodiment, encoder 8 is to comprise the magnetic encoder of encoder with magnet 81 and MR transducer 82 (Magnetic Sensor/magnetic resistance effect transducer), wherein, above-mentioned encoder is cylindric with magnet 81, be installed on the end of the anti-outlet side L2 of rotating shaft 31, above-mentioned MR transducer and encoder magnet 81 subtends.

When constituting above-mentioned encoder 8, encoder is parts that give prominence to the end of the anti-outlet side L2 of stator 2 from rotating shaft 31 on axis direction with magnet 81, remains on axis the part away from the end of the anti-outlet side L2 of rotor magnet 32.So encoder remains in the shaft end side of more depending on anti-outlet side L2 in the rotating shaft 31 than bearing 59, bearing keeper 58 with magnet 81.As shown in Figure 7, above-mentioned encoder is to have and the magnet sheet 320 same outer diameter as sizes that constitute rotor magnet 32 and the magnet cylindraceous of internal diameter size with magnet 81, is formed with the S utmost point and the N utmost point at outer peripheral face with the phase alternation ground identical with magnet sheet 320.So, also encoder can be used magnet 81 directly be used as the magnet sheet 320 of rotor magnet 32.

Shown in Fig. 2 (a) and Fig. 8 (a), Fig. 8 (b), Fig. 8 (c), MR transducer 82 along axis direction away from the position of stator 2 and encoder with magnet 81 subtends.More specifically, MR transducer 82 is installed on the surperficial 85a of the outlet side L1 of the discoideus sensor base plate 85 that disposes in the mode with the end subtend of the anti-outlet side L2 of rotating shaft 31.Therefore, MR transducer 82 is with respect to the opposite side (anti-outlet side L2) and encoder magnet 81 subtends of encoder with magnet 81 stator 2 places one side on the axis direction of rotating shaft 31.On the surperficial 85b of the anti-outlet side L2 of sensor base plate 85, be equipped with and drive, drive and according to the testing result of encoder 8 FEEDBACK CONTROL is carried out in the energising of

coil

24,29 with IC79 with IC79, other electronic components 78.Sensor base plate 85 is PCB substrate, glass-such rigid substrates such as epoxy substrate.

End at lid 9 anti-outlet side L2 is equipped with encoder housing 80, this encoder housing 80 is metal, have the tube portion 801 that MR transducer 82, sensor base plate 85 is surrounded at outer circumferential side, maintain the peripheral end 851 of sensor base plate 85 at the inner peripheral surface 802 of above-mentioned tube portion 801.Inner peripheral surface 802 in encoder housing 80 is formed with circular stage portion 806, and peripheral end 851 butts of above-mentioned stage portion 806 and sensor base plate 85 are to position sensor base plate 85.Form porosely 808 on encoder housing 80, this hole 808 will be used for fixing, the lead of bearing keeper 58, and (Japanese: fixing screw 89 グラ Application De) is fixed with ground.

Under this state, there is MR transducer 82 and encoder magnet 81 in the space of in the tube portion 801 of encoder housing 80, being sealed by sensor base plate 85.But, be formed with through hole 801a in the tube portion 801 of encoder housing 80, this through hole 801a makes space and the external communications that contains MR transducer 82 and encoder usefulness magnet 81.Above-mentioned through hole 801a makes air contain MR transducer 82 and encoder in the inside of encoder housing 80 and flows into flowing out between the space of magnet 81 and the outside.

In addition, the position that avoid being equipped with MR transducer 82 in sensor base plate 85, drive zone with IC79, electronic component 78, is formed with the zone of distribution is formed with through hole 85e, and this through hole 85e makes and covers space and the external communications that contains MR transducer 82 and encoder usefulness magnet 81 in 9 the inboard.Above-mentioned through hole 85e makes air contain MR transducer 82 and encoder in the inside of encoder housing 80 and flows into flowing out between the space of magnet 81 and the outside.

In addition, shown in Fig. 9 (a), Fig. 9 (b), a plurality of positions of circumferentially separating on the edge of the peripheral end 851 of sensor base plate 85 are formed with towards the outstanding projection 852 of radial outside.Therefore, the part between the projection 852 becomes minor diameter part 853 in the outer circumference end board 851 of sensor base plate 85.So, under the state of tube portion 801 inboards that sensor base plate 85 are contained in encoder housing 80, the projection 852 that the peripheral end 851 of sensor base plate 85 only separates to make progress in week and inner peripheral surface 802 butts of tube portion 801, thus between the inner peripheral surface 802 of minor diameter part 853 and tube portion 801, be formed with clearance G a.Above-mentioned clearance G a makes air contain MR transducer 82 and encoder in the inside of encoder housing 80 and flows into flowing out between the space of magnet 81 and the outside.In addition, because the clearance G a between the inner peripheral surface 802 of sensor base plate 85 and tube portion 801 has reduced the contact area of encoder housing 80 with sensor base plate 85, therefore also played the function of inhibition heat transmission of 85 from encoder housing 80 towards sensor base plate.

(manufacture method of stepping motor 100)

When making the stepping motor 100 of present embodiment, in rotor forms operation, at first, from the cut-and-dried magnet sheet 320 of the length that meets stator 2, get the magnet sheet 320 of the given size of requirement, be fixed in rotating shaft 31 around, magnetize and form rotor magnet 32.Perhaps, after with bonding agent a plurality of magnet sheets 320 being linked around the anchor clamps, magnetize forming rotor magnet 32, and with above-mentioned rotor magnet 32 be fixed in rotating shaft 31 around.

On the other hand, form in the operation at stator, the B phase coil 29, the B phase external stator iron core 26 that make A phase external stator iron core 21, be wound in A phase coil 24, A phase internal stator iron core 22, B phase internal stator iron core 27 on the bobbin 23, are wound on the bobbin 28 are overlapping on motor axis L direction, to form stator pack 20.Before carrying out above-mentioned operation, dividing plate 5 is welded to the base plate 211 of A phase external stator iron core 21.Can not carry out spot welding in the interior rear flank that

coil

24,29 etc. is disposed at A phase external stator iron core 21, even if but be the base plate of the A phase external stator iron core 21 of R shape, also dividing plate 5 can be welded in this base plate.

Then, pass a plurality of stator pack 20 in the mode of the anchor clamps that run through the pole shape, thereby a plurality of stator pack 20 are configured to coaxial shape.At this moment, make another anchor clamps and terminal 246,296 or terminal board 231,281 butts, and carry out the angular adjustment of a plurality of stator pack 20.

Then, after terminal 246,296 is embedded the terminal hole 70 of substrate 7, carry out the soldering of the weld part of terminal 246,296 and substrate 7.Before carrying out above-mentioned soldering or after finishing above-mentioned soldering, the dividing plate 5 of external stator iron core 21 is fixing mutually with the leading section of the cylindrical portion 212 of A phase external stator iron core 21 and the A that is fixed in adjacent stator pack 20 by laser welding.Laser welding can not partly be carried out at R, but in the present embodiment, because leading section and dividing plate 5 rectangular in the cylindrical portion 212 of A phase external stator iron core 21 or approximate right angle are welded together, therefore, can adopt laser welding.Above-mentioned laser welding is different with spot welding, has advantages such as following: even if by A phase external stator unshakable in one's determination 21 with the B space that external stator iron core 26 surrounds mutually in carry out above-mentioned laser welding after dispose

coil

24,29 etc.,

coil

24,29 is damaged.

In addition, in the present embodiment, embed the flange part 261 that B phase external stator iron core 26 is arranged at the leading section of the cylindrical portion 212 of A phase external stator iron core 21, the front end of cylindrical portion 212 is in the state identical with thickening.Therefore, be laser-welded to a time-out, can not occur in perforate in the cylindrical portion 212 of A phase external stator iron core 21, make unfavorable conditions such as coil 29 damages or broken string at leading section and dividing plate 5 with the cylindrical portion 212 of A phase external stator iron core 21.In addition, since with A mutually external stator iron core 21 cylindrical portion 212 laser welding together be and the A phase external stator of adjacent stator pack 20 21 means of spot welds unshakable in one's determination dividing plate 5 together, therefore, when laser welding, also can not occur in A phase external stator 21 perforates unshakable in one's determination of adjacent stator pack 20, make unfavorable conditions such as coil 24 damages or broken string.Therefore, stator pack 20 constant intensity each other can be improved, and the rate of finished products of stepping motor 100 can be improved.

After having assembled stator 2 like this, dispose the first lid member 91 and the second lid member 92 in the mode of clamping stator 2, and utilize clamp structure 99 that the first lid member 91 and the second lid member 92 are linked, cover 9 thereby constitute.Then, flange 50 is fixed in covers 9.

Then, by bearing 57,59 and bearing

keeper

56,58 etc., rotor 3 is disposed in the stator 2 in revolvable mode.At this moment, the encoder that is used to constitute encoder 8 is installed with magnet 81 in the end of the anti-outlet side L2 of rotating shaft 31.Then, encoder housing 80 is installed on lid 9.At this moment, will MR transducer 82 be installed, drive the inboard that is installed on encoder housing 80 with the sensor base plate 85 of IC79, electronic component 78 and connector 77.

(the main effect of present embodiment)

As mentioned above, in the stepping motor 100 of present embodiment, a plurality of stator pack 20 are configured on the motor axis L direction, and between a plurality of stator pack 20, make the angle position of utmost point tooth 215,225,265,275 identical, therefore, can be that the state of higher transmission precision obtains bigger torque down with the speciality of guaranteeing stepping motor 100.In addition, owing to be that a plurality of stator pack 20 are configured in structure on the motor axis L direction, therefore, it is less that the outside dimension of stepping motor 100 keeps.

In addition, in the present embodiment, stator pack 20 comprises that A phase stator core (external stator unshakable in one's determination 21 and internal stator iron core 22) and coil 24, B phase stator core (external stator unshakable in one's determination 26 and internal stator iron core 27) and coil 29 are as stator core and coil, between a plurality of stator pack 20, A phase utmost point tooth 215,225 angle position each other is identical, and B phase utmost point tooth 265,275 angle position each other is identical.If adopt above-mentioned two phase structure, then different with phase structure, the vibration in the time of transmission being moved etc. suppresses lowlyer.

In addition, between a plurality of stator pack 20, stator core (external

stator iron core

21,26 and internal stator iron core 22,27) and

coil

24,29 are identical structure.So, can realize the shared of part, therefore, can realize the cost degradation of stepping motor 100.

In addition, in the present embodiment, lid 9 comprises the first lid member 91 and the second lid member 92 (radiating component), this the first lid member 91 and the second lid member 92 are metal, have the inner peripheral surface 93 that bends to the peripheral shape correspondingly-shaped of stator 2, the inner peripheral surface 93 of the above-mentioned first lid member 91 and the second lid member 92 directly contacts with the peripheral part 200 of stator 2 with bigger contact area.And the first lid member 91 and the second lid member 92 have the area outer peripheral face 94 bigger than the area of inner peripheral surface 93.Therefore, the first lid member 91 and the second lid member 92 have excellent thermal diffusivity.So, the heat that produces in the stator 2 can be dispelled the heat efficiently by the first lid member 91 and the second lid member 92.Therefore, the temperature of stator 2 can be risen and suppress lowlyer, thus the generation of the unfavorable condition that to prevent that coil 24,29 (stator coil) from burning out etc. such.

Especially, in the stepping motor 100 of present embodiment, owing to be provided with a plurality of stator pack 20, therefore, the heating in the stator 2 is bigger, but the heat that produces in the stator 2 can be dispelled the heat efficiently by the first lid member 91 and the second lid member 92.In addition, stator 2 is made of a plurality of stator pack 20, but the first lid member 91 and the second lid member 92 are in the state of clamping a plurality of stator pack 20 and linking.Therefore, stator 2 is in by the state of the

first lid member

91 and 92 reinforcements of the second lid member, thereby the situation that stator pack 20 linking part each other comes off can not occur.

In addition, in the present embodiment, because stator 2 is cylindric, therefore, the inner peripheral surface 93 of the first lid member 91 and the second lid member 92 is circular-arc recessed flexure plane, but outer peripheral face 94 is prismatic.Therefore, in the first lid member 91 and the second lid member 92, form the area structure bigger of outer peripheral face 94 than the area of inner peripheral surface 93, so, heat dispersion can be improved.In addition, although stator 2 is cylindric, the outer peripheral face 94 of the first lid member 91 and the second lid member 92 is prismatic.Therefore, can utilize the outer peripheral face 94 of the first lid member 91 and the second lid member 92 that stepping motor 100 is installed on the motor apparatus, so, motor had towards advantages such as the installation of motor apparatus are easy.

In addition, the first lid member 91 and the second lid member 92 are aluminums.If the first lid member 91 of above-mentioned aluminum and the second lid member 92, then because its pyroconductivity is higher, so, good heat dissipation effect, and low price.

In addition, in the stepping motor 100 of present embodiment,, therefore, can use encoder 8 to detect the angle position of rotating shaft 31, and can feed back this result owing in rotating shaft 31, constitute encoder 8.So, can prevent the generation of the step-out of stepping motor 100.

In addition, when constituting encoder 8, in rotating shaft 31 from the end of stator 2 along the outstanding part of axis direction promptly along axis direction away from the part configuration codes device of the end of rotor magnet 32 with magnet 81, be provided with MR transducer 82 with magnet 81 in position with respect to above-mentioned encoder away from stator 2.And, encoder remains in the rotating shaft 31 than bearing 59, bearing keeper 58 more by the shaft end side of anti-outlet side with magnet 81, MR transducer 82 with respect to encoder with magnet 81 on the axis direction of rotating shaft 31 with an opposite side and encoder usefulness magnet 81 subtends of stator 2 places one side.Therefore, can make MR transducer 82, so when stator was powered, even stator 2 heatings, above-mentioned heat also was difficult for being passed to MR transducer 82 fully away from stator 2.Especially, in the stepping motor 100 of present embodiment, owing to be provided with a plurality of stator pack 20, therefore, the heating in the stator 2 is bigger, even but stator 2 heatings, above-mentioned heat also is difficult for being passed to MR transducer 82.Therefore, can suppress MR transducer 82 and become high temperature, so, can prevent that the flase drop that the temperature because of MR transducer 82 causes from surveying, and can realize the long lifetime of MR transducer 82.

In addition, be formed with through hole 801a in the tube portion 801 of encoder housing 80, this through hole 801a makes air contain MR transducer 82 and encoder in the inside of encoder housing 80 to flow out between with the space of magnet 81 and outside and flow into.In addition, be formed with through hole 85e on sensor base plate 85, this through hole 85e makes air contain MR transducer 82 and encoder in the inside of encoder housing 80 to flow out between with the space of magnet 81 and outside and flow into.In addition, because of minor diameter part 853 is formed with clearance G a, above-mentioned clearance G a makes air contain MR transducer 82 and encoder in the inside of encoder housing 80 to flow out between with the space of magnet 81 and outside and flow between the inner peripheral surface 802 of the tube portion 801 of the peripheral end 851 of sensor base plate 85 and encoder housing 80.So, even be provided with in the inboard of encoder housing 80 under the situation of MR transducer 82, also can carry out the heat radiation of MR transducer 82, therefore, the temperature that can suppress MR transducer 82 rises.Therefore, can suppress MR transducer 82 and become high temperature, so, can prevent that the flase drop that the temperature because of MR transducer 82 causes from surveying, and can realize the long lifetime of MR transducer 82.

In addition, the clearance G a between the inner peripheral surface 802 of sensor base plate 85 and tube portion 801 suppresses from encoder housing 80 towards sensor base plate 85 heat transmission.Therefore, the heat that can suppress stator 2 is passed to MR transducer 82 via encoder housing 80 and sensor base plate 85.Therefore, can suppress MR transducer 82 and become high temperature, so, can prevent that the flase drop that the temperature because of MR transducer 82 causes from surveying, and can realize the long lifetime of MR transducer 82.

In addition, under the situation of using a plurality of stator pack 20, when coil 24 being reached coil 29 each other be connected in parallel with each other, may produce unbalanced to the electric current that in

coil

24,29, flows, but in the present embodiment, owing to coil 24 is reached coil 29 connections that be one another in series each other, therefore, can make the electric current that in the

coil

24,29 of each stator pack 20, flows equal.

In addition, in the present embodiment, between a plurality of stator pack 20, the position of terminal 246,296 is positioned at identical angle position, therefore, is easy towards the electrical connection of terminal 246,296.In addition, when stator pack 20 is disposed at identical angle position, can be the angle position that benchmark is regulated stator pack 20 with terminal 246,296 or terminal board 231,281.And, because the position of terminal 246,296 is positioned at identical angle position, therefore, all terminals 246,296 are connected with shared substrate 7, become easy thereby make towards the electrical connection of terminal 246,296.In addition, owing to use rigid substrates as substrate 7, therefore different with the situation of using flexible base, board, having can be by the such advantage of the offset that fixedly prevents stator pack 20 of terminal 246,296 and substrate 7.

In the present embodiment, in rotor magnet 32, identical magnetic pole integrally forms on motor axis L direction continuously, and therefore, the regional integration with stator 2 subtends in the rotor magnet 32 is magnetized.Therefore, magnetic efficiency is higher, so, be favourable for obtaining bigger torque.

In addition, rotor magnet 32 is made of a plurality of magnet sheets 320 that dispose on motor axis L direction, therefore, can wait the total length of regulating rotor magnet 32 by the quantity that only changes magnet sheet 320.So, can reduce the kind of the part of rotor magnet 32 usefulness that will prepare, thereby can reduce the cost of stepping motor 100.And, because a plurality of magnet sheets 320 dispose in adjacent magnet sheet 320 modes against each other, therefore, can easily realize the structure that the part with stator 2 subtends all is magnetized.

(the affirmation result of the effect of radiating component)

Figure 10 (a) is the chart of variations in temperature of the each several part of expression stepping motor shown in Figure 1, and Figure 10 (b) is the chart of variations in temperature of each several part of the stepping motor of expression reference example.The reference example of expression variations in temperature is another stepping motor in Figure 10 (b), this stepping motor adopts following structure: the plate-like cover member that uses the cross section to be the コ font replaces with reference to the first lid member 91 of Fig. 1, Fig. 3 and Fig. 4 explanation and the second lid member 92, and the inner peripheral surface of plate-like cover member is different fully with the peripheral shape of stator 2 cylindraceous.Other structures of the stepping motor of reference example are with identical with reference to the structure of Fig. 1～Fig. 9 explanation.

In addition, the variations in temperature of each position after the evaluation result shown in Figure 10 (a), Figure 10 (b) is represented stator 2 begun to switch on, each line of chart is represented the variations in temperature with upper/lower positions.

In Figure 10 (a)

Solid line L10: the room temperature in the evaluation

Solid line L11: the surface temperature of

coil

24,29

Chain-dotted line L12: the surface temperature of lid 9

Solid line L13: the temperature of encoder 8

Chain-dotted line L14: the temperature of the bearing 96 of outlet side

Dotted line L15: the temperature of the bearing 57 of anti-outlet side

In Figure 10 (b)

Solid line L20: the room temperature in the evaluation

Solid line L21: the surface temperature of coil

Chain-dotted line L22: the surface temperature of motor

Solid line L23: the temperature of encoder 8

Chain-dotted line L24: the temperature of the bearing 96 of outlet side

Dotted line L25: the temperature of the bearing 57 of anti-outlet side

Relatively Figure 10 (a) can obtain following result with Figure 10 (b): in using stepping motor 100 of the present invention, the temperature of the temperature of the bearing 96 of the surface temperature of the surface temperature of

coil

24,29, lid 9, the temperature of encoder 8, outlet side, the bearing 57 of anti-outlet side is all hanged down about 10 ℃ than the temperature of reference example.

(the improvement example of radiating component)

Figure 11 is the key diagram that the improvement example of the radiating component that uses in the stepping motor of the present invention is used in expression.Because the basic structure of present embodiment is identical with the basic structure of above-mentioned execution mode, therefore, the common identical symbol of part mark is illustrated, and omit its detailed explanation.

As shown in figure 11, the radiating component that uses in the stepping motor 100 of present embodiment (the first lid member 91 and the second lid member 92) is formed with a plurality of breach 95a on heat radiation board 95.Therefore, the part between breach 95a is formed with radiated rib 95b.If constitute like this, then has the such advantage of thermal diffusivity that can further improve the first lid member 91 and the second lid member 92.

(other radiating components)

Figure 12 is the key diagram that other radiating components that use in the stepping motor of the present invention are used in expression.Because the basic structure of present embodiment is identical with the basic structure of above-mentioned execution mode, therefore, the common identical symbol of part mark is illustrated, and omit its detailed explanation.

As shown in figure 12, the radiating component 98 that uses in the present embodiment is metal tabular components such as aluminium, and the lower end side of radiating component 98 forms circular-arc corresponding to the peripheral shape of stator 2.Therefore, the inner peripheral surface 98a of radiating component 98 form with the circular-arc recessed flexure plane of the roughly the same curvature bending of the curvature of the peripheral part 200 of stator 2.In addition, the upper end of radiating component 98 forms the heat radiation board 98c of the heavy wall that the outside side stretches out, and the area of the outer peripheral face 98b of radiating component 98 is bigger than the area of inner peripheral surface 98a.

Above-mentioned radiating component 98 uses with the mode that the peripheral part 200 of stator 2 directly contacts to bend to circular-arc inner peripheral surface 98a.Therefore, stator 2 is bigger with the contact area of radiating component 98, so, the heat that produces in the stator 2 can be dispelled the heat efficiently by radiating component 98.Therefore, the temperature of stator 2 can be risen and suppress lowlyer, thus the generation of the unfavorable condition that to prevent that coil 24,29 (stator coil) from burning out etc. such.

(variation of radiating component)

Figure 13 is the key diagram that the variation of the lid (radiating component) that uses in the stepping motor of the present invention is used in expression, Figure 13 (a) is the stereogram that disposes the upper portion of connector in the stepping motor, Figure 13 (b) is the stereogram that disposes the lower portion of connector in the stepping motor, and Figure 13 (c) is the longitudinal section of stepping motor.Because the basic structure of present embodiment is identical with the basic structure of above-mentioned execution mode, therefore, the common identical symbol of part mark is illustrated, and omit its detailed explanation.

Shown in Figure 13 (a), Figure 13 (b), Figure 13 (c), the stepping motor 100 of present embodiment is identical with above-mentioned execution mode, cover 9 by on motor axis L direction, constituting, thereby the peripheral part 200 of stator 2 is all covered towards the second lid member 92 of the upper end side of the first lid member 91 of the bottom side of long side direction and covering stator 2 and covering stator 2.In addition, because near the upper end arrival substrate 7 of the first lid member 91 of above-mentioned execution mode and the second lid member 92, therefore, substrate 7 is between the upper end that the first lid member 91 and second covers member 92 from covering 9 states that expose, but in the present embodiment, because utilize the second lid member, 92 covered substrates 7, therefore, the substrate 7 that is positioned on the stator 2 can not expose from covering 9.

At this, in the above-described embodiment, adopt inner peripheral surface 93 and the inner peripheral surface 98a of radiating component 98 and the peripheral part 200 direct contacting structure of stator 2 of radiating component (the first lid member 91 and the second lid member 92), but in the present embodiment, shown in Figure 13 (c), between the peripheral part 200 of lid 9 inner peripheral surface 93 and stator 2, on its full week, be formed with space part, in this space part, be filled with resin 6.In addition, above-mentioned resin 6 is filled to the position that covers

coil

24,29 in the inside of stator 2.

Under the situation that adopts said structure, the peripheral part 200 of stator 2 is used as and covers 9 radiating component (the first lid member 91 and the second lid member 92) and cover, be filled with resin 6 in the space part between the peripheral part 200 of lid 9 inner peripheral surface 93 and stator 2, and above-mentioned resin 6 arrives

coil

24,29, therefore, the heat that produces in the

coil

24,29 is passed to via resin 6 covers 9, so thermal diffusivity is better.Promptly, even under the situation of using a plurality of stator pack 20, the heat (the especially heat that produces in the coil 24,29) that produces in the stator 2 is passed to via resin 6 covers 9 (radiating components), to improve thermal diffusivity, therefore, the temperature of stepping motor 100 can be risen and suppress lowlyer, thereby can improve the reliability of stepping motor 100.

(other execution modes)

In the above-described embodiment, stator pack 20 is 5, but also the quantity of stator pack 20 can be made as 2～4 or more than 6.In addition, also the present invention can be used in stator pack 20 is in the motor beyond 1 the stepping motor 100, stepping motor.In addition, in the above-described embodiment, dividing plate 5 is made of magnetic material, but also can be made of nonmagnetic substance.In addition, in the above-described embodiment, substrate 7 is rigid substrates, but also can be flexible base, board.

In the above-described embodiment, adopt inner peripheral surface 93 and the inner peripheral surface 98a of radiating component 98 and the peripheral part 200 direct contacting structure of stator 2 of radiating component (the first lid member 91 and the second lid member 92), but also can adopt following structure: between the peripheral part 200 of the inner peripheral surface 98a of the inner peripheral surface 93 of radiating component (the first lid member 91 and second covers member 92) and radiating component 98 and stator 2, be provided with metal fin or metal, carbon dust be dispersed in the resin and the fin of formation.Under the situation that adopts said structure, the inner peripheral surface 93 of radiating component (the first lid member 91 and the second lid member 92) and the inner peripheral surface 98a of radiating component 98 contact with the peripheral part 200 of stator 2 across fin, but between the peripheral part 200 of radiating component and stator 2 is fin owing to be located at, therefore, the heat that produces in the stator 2 can be dispelled the heat efficiently via radiating component 98.

Claims

1. stepping motor comprises:

Rotor, this rotor have at outer peripheral face along the rotor magnet and the rotating shaft that circumferentially alternately are formed with the N utmost point and the S utmost point; And

Stator with the tubular of the outer peripheral face subtend of described rotor magnet is characterized in that,

Described stator disposes a plurality of single-phase or heterogeneous stator pack on the motor axis direction, this stator pack has the stator core of disposing a plurality of utmost point teeth annularly and is centered around the coil of described utmost point tooth outer circumferential side,

The angle position of described utmost point tooth is identical between described a plurality of stator pack.

2. stepping motor as claimed in claim 1 is characterized in that,

Described stator pack comprises the stator core of A phase and coil, the stator core of B phase and coil as described stator core and described coil,

Between described a plurality of stator pack, A phase utmost point tooth angle position each other is identical, and B phase utmost point tooth angle position each other is identical.

3. stepping motor as claimed in claim 2 is characterized in that,

Between described a plurality of stator pack, described stator core and described coil have identical structure.

4. stepping motor as claimed in claim 1 is characterized in that,

In belonging to the described coil of described a plurality of stator pack, corresponding to the connection that is one another in series of the coil of phase homophase.

5. stepping motor as claimed in claim 1 is characterized in that,

Outer circumferential side in described stator pack is provided with the terminal that is used for described coil power supply,

Between described a plurality of stator pack, the position of described terminal is positioned at the equal angular position.

6. stepping motor as claimed in claim 1 is characterized in that,

The a plurality of terminals that form in described a plurality of terminal group by soldering on the conductive pattern that is formed on the common substrate.

7. stepping motor as claimed in claim 6 is characterized in that,

Described substrate is a rigid substrates.

8. stepping motor as claimed in claim 1 is characterized in that,

In described rotor magnet, same pole integrally forms on the motor axis direction continuously.

9. stepping motor as claimed in claim 8 is characterized in that,

Described rotor magnet is made of a plurality of magnet sheets along the configuration of motor axis direction.

10. stepping motor as claimed in claim 9 is characterized in that,

Described a plurality of magnet sheet is configured to adjacent magnet sheet against each other.

11. stepping motor as claimed in claim 9 is characterized in that,

In described a plurality of magnet sheets, contain the different magnet sheet of length dimension on the motor axial direction.

12. stepping motor as claimed in claim 9 is characterized in that,

The quantity of described magnet sheet is different with the group number of described stator pack.

13. stepping motor as claimed in claim 1 is characterized in that,

The outer circumferential side tegmentum of described stator covers,

Between described lid and described stator, be filled with resin.

14. stepping motor as claimed in claim 1 is characterized in that,

Dispose dividing plate between the adjacent stator pack in described a plurality of stator pack,

Described dividing plate welds together with the stator core of clamping the stator pack of this dividing plate in both sides.

15. stepping motor as claimed in claim 14 is characterized in that,

In arbitrary electronics group in described a plurality of stator pack, the outer peripheral edges of the side end on the motor axis direction are the right angle part or the approximate right angle part of stator core, and the outer peripheral edges of the end side on the motor axial direction are the R part of stator core,

The stator core that is positioned at a described side end is laser-welded to described dividing plate, and the stator core that is positioned at described end side is spoted weld described dividing plate.

16. stepping motor as claimed in claim 1 is characterized in that,

End in described rotating shaft disposes encoder,

Testing result according to described encoder is carried out FEEDBACK CONTROL to the energising of described coil.

17. stepping motor as claimed in claim 1 is characterized in that,

Have radiating component, this radiating component is provided with the inner peripheral surface that bends to the peripheral shape corresponding shape of described stator,

The inner peripheral surface of described radiating component directly or across fin contacts with the peripheral part of described stator.

18. stepping motor as claimed in claim 17 is characterized in that,

Have a plurality of described radiating components,

Described a plurality of radiating component links across a plurality of described stator pack.

19. stepping motor as claimed in claim 17 is characterized in that,

Described radiating component has the area outer peripheral face bigger than the area of described inner peripheral surface.

20. stepping motor as claimed in claim 19 is characterized in that,

Described stator is cylindric,

The described inner peripheral surface of described radiating component is circular-arc recessed flexure plane, and the described outer peripheral face of described radiating component is prismatic.

21. stepping motor as claimed in claim 19 is characterized in that,

Have lid with the periphery covering of described stator,

Described radiating component is used as the lid member that constitutes described lid.

22. stepping motor as claimed in claim 17 is characterized in that,

Be provided with at the outer peripheral face of described stator and be used for substrate that described stator is powered,

Described substrate is in the state that exposes from described radiating component.

23. stepping motor as claimed in claim 17 is characterized in that,

Described radiating component is an aluminum.

24. stepping motor as claimed in claim 17 is characterized in that,

Described radiating component is across the linking part of the outer peripheral face of the adjacent a plurality of described stator pack described stator pack adjacent with this.