STEPPER MOTOR

Abstract

Stepper motor, characterized in that this a rotor that has a shaft, a stator arranged adjacent to the rotor, and a plate which is arranged opposite one axial end of the rotor and has a support section supporting the shaft, wherein the plate has an annular projection which is formed in one piece on the surface facing the rotor, projects towards the rotor side and surrounds the shaft, wherein a helical spring is provided within the projection, which in the state placed on the shaft is supported between the plate and the rotor, preloads the rotor in the axial direction towards the other end side and elastically presses the rotor against other components, and several extensions are formed on the end face of the projection such that the extensions surround the helical spring.

Description

[Technical field]

[0001] The present invention relates to a stepper motor. [Background technology]

[0002] Traditionally, a stepper motor is known to be attached directly to a printed circuit board (see, for example, patent document 1). Fig. Figure 7 shows a stepper motor similar to the one specified in this document, wherein this motor has a structure in which a rotor 20 consisting of a shaft 21, a rotor component 22 and a rotor magnet 23 is accommodated within a stator 10, and a front plate 30 and an end plate 40 are attached to both sides of the axial direction of the stator 10, and is attached to a printed circuit board 70.

[0003] The front panel 30 comprises a positioning pin (not shown) with which positioning on the circuit board 70 is carried out, an extension 31 which is fitted into the circuit board 70, a connecting pin 32 which is soldered to the circuit board 70, and a fastening pin 33 which does not function as an electrode and is soldered to the circuit board 70, wherein the motor is attached to the circuit board 70 by fitting the extension 31 into the circuit board 70 and soldering the connecting pin 32 and the fastening pin 33 directly to the circuit board 70. In the motor, rubber washers 50, 60 are arranged between the rotor component 22 of the rotor 20, the front plate 30 and the end plate 40, each fitted into the shaft 21, the motor being constructed in such a way that these rubber washers 50, 60 absorb effects caused by axial rattling of the rotor 20. [Patent documents]

[0004] [Patent document 1] JP 2014-027843 A DE 10 2004 014 865 A discloses a disc rotor motor with rotor and stator, closed at one end by a cover. The cover rests against a rolling bearing. To maintain the intended air gap width, a motor shaft compression spring and a stator compression spring are provided. The motor shaft compression spring is supported by a pressure ring connected to the motor shaft and the outer ring of the rolling bearing furthest from the output, thereby compensating for the bearing play of the rolling bearings. The stator compression spring is arranged in an annular groove in the cover and presses the stator against a stator stop, thus compensating for the manufacturing and assembly play of the stator. Similar prior art is described in DE 10 13 133 B. A stepper motor is disclosed in US 2007 / 0 170 797 A1. [Technical task]

[0005] The area is located in Fig. In the motor shown in Figure 7, variations occur between the dimensions of the respective components and the dimensions in the assembled state. During assembly, a gap can form between the rubber washers 50, 60, which are set to a specific height dimension (thickness in the axial direction), and the rotor component 22 of the rotor 20. If such a gap forms, axial play of the rotor 20 cannot be absorbed, resulting in the rotor component 22 striking the rubber washers 50, 60 and generating noise.While it is conceivable to adjust the thickness of the rubber washers 50, 60 according to the fluctuations that occur, this would require providing a large number of different rubber washers with varying thicknesses to compensate for the fluctuations. This would increase the number of components and decrease work efficiency, ultimately leading to increased costs.

[0006] The present invention was made in view of the foregoing circumstances and aims to provide a stepper motor in which noises caused by the formation of gaps between an axially arranged rotor and a plate are suppressed even when there are variations between the dimensions of the components and the assembly condition, and moreover, such a structure can be achieved without increasing costs. [Solution to the task]

[0007] The stepper motor of the present invention is defined in claim 1. Embodiments are specified in the dependent claims.

[0008] According to the invention, the rotor, pre-tensioned by the coil spring, is pressed elastically against the other components. This suppresses noise caused by gaps between an axially arranged rotor and a plate, even when there are variations in the components and the assembled state. Furthermore, since the structure is simple, noise reduction is achieved without increasing costs. In the present invention, "pressing the rotor elastically against the other components" naturally includes both situations where the rotor is in direct contact with the other components and situations where a component such as a washer is arranged between the rotor and the other components.

[0009] The present invention includes a design in which the axial height of the projection facing the rotor is greater than the block length of the helical spring. According to this design, the rotor, for example when large forces act upon it and it moves in the direction of the plates, contacts the projection before the helical spring reaches its compressed height. This prevents damage to the helical spring.

[0010] Furthermore, the present invention includes a form in which the plate has a terminal block to which terminal pins are provided for connecting the stator coils, and comprises a flange section, wherein the flange section has mounting pins for attachment to a mounting component. According to this form, the stepper motor of the present invention can be attached to a mounting component by means of the mounting pins.

[0011] Furthermore, the present invention includes a shape in which the flange section of the plate extends radially, wherein a plurality of these flange sections are formed.

[0012] Furthermore, the present invention includes a form in which the other components are a plate arranged on the axially opposite end side of the rotor.

[0013] The stepper motor according to the invention ensures that noises caused by the formation of gaps between an axially arranged rotor and a plate are suppressed even when there are variations between the dimensions of the components and the assembled state, and moreover, such a structure can be achieved without increasing costs. [Brief explanation of the characters] [ Fig. 1] Fig. Figure 1 is a perspective view of a stepper motor according to an embodiment of the present invention. [ Fig. 2] Fig. Figure 2 is a cross-section of a stepper motor of the embodiment. [ Fig. 3] Fig. 3 (A) is a perspective view and (B) a cross-section showing a projection of a front panel. [ Fig. 4] Fig. Figure 4 is a perspective view of a stepper motor according to another embodiment of the present invention. [ Fig. 5] Fig. Figure 5 is a front view of the stepper motor of the other embodiment. [ Fig. 6] Fig. Figure 6 is a cross-section of the stepper motor of the other embodiment. [ Fig. 7] Fig. Figure 7 is a cross-section of a conventional stepper motor. [Forms for carrying out the present invention]

[0014] The following section explains embodiments of the present invention with reference to the figures. [1] First embodiment[1-1] Stepper motor structure

[0015] Fig. 1 and Fig. Figure 2 shows a claw-pole stepper motor 100A according to a first embodiment. The stepper motor 100A has a stator structure in which an annular front stator arrangement (stator) 200 and an end stator arrangement (stator) 300 are coaxially connected, with a rotor 400 having a shaft 403 freely rotating on their inner surface. The respective stator arrangements 200, 300 are clamped between a disk-shaped front plate 210 and an end plate (further component) 310, each arranged on the axial outer surface, and in the connected state held by these plates 210, 310, form the stepper motor 100A.

[0016] The reference number 600 in Fig. 2 is a printed circuit board (mounting component) that is equipped with various electronic components, and the stepper motor 100A is attached to this printed circuit board 600 in the state of the front panel 210 adapted to the printed circuit board 600.

[0017] The front stator arrangement 200 and the end stator arrangement 300 have the same construction and are each formed from a shell-shaped outer yoke 220, a coil former 230, and a disc-shaped inner yoke 240. As shown in Fig. As shown in Figure 2, the outer yoke 220 comprises an annular base section 221 and a cylindrical section 222 extending axially from the outer circumferential edge of the base section 221. A plurality of axially projecting pole teeth 223, in the form of comb teeth, are arranged at the edge of an opening formed in the center of the base section 221. Conversely, a plurality of axially projecting pole teeth (not shown), in the form of comb teeth, are arranged at the edge of a central opening in the inner yoke 240. The outer yoke 220 and the inner yoke 240 are connected to each other in a state in which the respective pole teeth engage with each other in specific gaps located between them.

[0018] The coil former 230 is made of plastic, wound with coils 231, and is received in an annular space inside the outer yoke 220 and the inner yoke 240, which are connected as described above. The coil former 230 comprises a connection section 232, and metal terminals 233 are embedded in the connection section 232, into which the ends of the windings of the coils 231 are connected. The stator assemblies 200, 300 with the above configuration are connected to one another such that the inner yokes 240 are aligned and axially opposed to each other.

[0019] The front panel 210 serves to form a front-facing housing and is made of plastic. As in Fig. As shown in Figure 1, the front plate 210 has a pair of ribbon connection sections 211 on the left and right sides, which extend along its outer edge section towards the end stator assembly 300. The ribbon connection sections 211 include claw sections 212 projecting outwards. The ribbon connection sections 211 are connected by a ribbon 500, thereby connecting the front stator assembly 200 and the end stator assembly 300.

[0020] At the upper section of the front panel 210 in Fig. 1 and Fig. 2 A terminal block 213 is formed in one piece, and a fastening pin arrangement section 217 is formed in one piece at the lower section. In addition, a substantially cylindrical extension 216 projecting axially to the outside is formed in one piece in the center of the front plate 210.

[0021] Four axially extending connecting pins 214 are embedded in the terminal block 213. The connecting pins 214 function as for the Fig. 2 shown circuit board 600 current-carrying terminals, wherein one end is attached to the circuit board 600 and the other end is connected to the terminals 233.

[0022] With the extension 216 in the middle, the mounting pin assembly section 217 is positioned symmetrically to the terminal block 213. Two axially projecting mounting pins 218 are attached to the mounting pin assembly section 217. The mounting pins 218 are essentially U-shaped metal components that are secured by pressing them into holes provided in the mounting pin assembly section 217. The mounting pins 218 are components used to attach the 100A stepper motor to the circuit board 600 and are made of a solderable material, but do not function as current-carrying terminals.

[0023] The extension 216 has a plurality of axially extending, slot-shaped grooves 216a. The inner diameter of the extension 216 is slightly larger than the shaft 403, and the shaft 403 passes through the inside of the extension 216. A bearing bore 215 is formed in the center of the front plate 210, through which the shaft 403 passes. The shaft 403 is displaceably in contact with an inner circumferential surface (support section) 215a of the bearing bore 215, and is held freely rotatable against the inner circumferential surface 215a.

[0024] Furthermore, as shown in the diagram, the terminal block 213 of the front panel 210 is equipped with Fig. Figure 1 shows an axially extending positioning pin 219 formed in one piece. The positioning pin 219 is fitted into a positioning hole (not shown) provided in the circuit board 600, thereby positioning the stepper motor 100A relative to the circuit board 600.

[0025] The end plate 310 of the end-side stator assembly 300 serves to form an end-side housing and is made of plastic. As shown in Fig. As shown in Figure 1, the end plate 310 has a pair of ribbon connection sections 311 on the left and right, which extend towards the front stator arrangement 200 such that they are opposite the ribbon connection sections 211 mentioned above. Furthermore, as shown in Fig. Figure 2 shows a bearing bore 315 in the center of the end plate 310, through which the shaft 403 passes. The shaft 403 is displaceably in contact with an inner circumferential surface (support section) 315a of the bearing bore 315, whereby the shaft 403 is held freely rotatable on the inner circumferential surface 315a.

[0026] As in Fig. As shown in Figure 2, the rotor 400 consists of a cylindrical rotor component 402, a rotor magnet 401 attached to the outer circumference of the rotor component 402, and the shaft 403, which passes through and is fixed to the center of the rotor component 402. The rotor magnet 401 has a magnetic pole structure with alternating NSNS magnetization in the direction of rotation. The shaft 403 passes through the bearing bores 215, 315 provided in the front plate 210 and the end plate 310, as described above, and is held freely rotatable by sliding in direct contact with the inner circumferential surfaces 215a, 315a of the bearing bores 215, 315. Alternatively, a configuration can be used in which the shaft 403 is held freely rotatable by a bearing device such as a roller bearing relative to the front plate 210 and the end plate 310.

[0027] As in Fig. As shown in Figure 1, the band 500 is an approximately C-shaped component made of a spring-like metallic material. It comprises a main section 505, which is mounted overlapping the outer surface of the end plate 310, and a pair of left and right arm sections 501 extending from the main section 505 to the front stator assembly 200. The band 500 is mounted by fitting a hole 505a formed in the center of the main section 505 onto a projection 312 formed in the center of the outer surface of the end plate 310.

[0028] Rectangular holes 501a are provided in the respective arm sections 501 of the belt 500. The belt 500 engages with the front plate 210 by the claw sections 212 of the belt connecting sections 211 of the front plate 210 being inserted into these holes 501a and interlocking, thereby connecting the front stator assembly 200 and the end stator assembly 300. The arm sections 501 of the belt 500 come into contact with the outside of the belt connecting section 311 of the end plate 310, whereby the arm sections 501 are in an elastically deformed state and the holes 501a interlock with the claw sections 212. This firmly connects the respective plates 210 and 310 to each other in alternating tension, and also ensures that the tape 500 does not detach from the front plate 210.

[0029] As in Fig. As shown in Figure 2, the circuit board 600 has a projection insertion hole 601, contact holes 602, and pin mounting holes 604. In addition, the positioning hole mentioned above (not shown) is also formed. In the stepper motor 100A of the present embodiment, the front panel 210 is adapted to the circuit board 600 when the positioning pin 219 is fitted into the positioning opening on the circuit board 600, the projection 216 is fitted into the projection insertion hole 601 by pressing it in, the end parts 214a of the connecting pins 214 are inserted into the contact holes 602, and the mounting pins 218 are inserted into the pin mounting holes 604.The stepper motor 100A is then attached to the circuit board 600 by soldering a copper foil 603, which forms a conductor pattern in the vicinity of the contact holes 602, and the connecting pins 214, and a copper foil 605 in the vicinity of the pin mounting holes 604 and the mounting pins 218. [1-2] Axial support structure of the rotor

[0030] The stepper motor 100A of the present embodiment has a structure by which noise is suppressed by eliminating axial rattling of the rotor 400. This structure is explained below.

[0031] As in Fig. As shown in Figure 2, an annular projection 700 is formed in one piece in the vicinity of the bearing bore 215 on the inner surface of the front plate 210, i.e., the surface opposite the rotor 400. At a front edge section of the projection 700, as shown in Fig. Figure 3 shows a plurality (in this case, three) of extensions 701, uniformly spaced apart from one another. The shaft 403 of the rotor 400 passes through the interior of the projection 700. A helical spring 800 is then accommodated inside the projection 700 in a position mounted on the shaft 403. In its compressed state, the helical spring 800 is arranged between the front plate 210 and the rotor component 402.

[0032] Washers 901 and 902, made of a material with good sliding properties such as plastic, are arranged between the coil spring 800 and the front plate 210, and between the coil spring 800 and the rotor component 402. A washer 903 of the same type is also arranged between the rotor component 402 and the end plate 310. The washers 901 to 903 are each mounted on the shaft 403. Furthermore, as shown in Fig. 3(B) shown, a maximum height H of the projection 700 in which the helical spring 800 is received, i.e. the axial dimension from the bottom surface inside the projection 700 (inner surface of the front plate 210) to the front end surface of the extensions 701 is set higher than the block length of the helical spring 800 (height with adjacent coils).

[0033] The coil spring 800 projects from the end face of the extensions 701 of the projection 700 and, via the washer 902, biases the rotor component 402 towards the side of the end plate 310. This causes the rotor component 402 to be elastically pressed against the end plate 310 via the washer 903, creating a gap between the rotor component 402 and the opposing end faces of the extensions 701. [1-3] Effects and impacts

[0034] In the present embodiment, the rotor 400 is biased towards the end plate 310 by the helical spring 800, whereby the rotor component 402 is always elastically pressed against the end plate 310 via the washer 903, and axial movement is restricted. Therefore, axial rattling of the rotor 400 is absorbed and noise suppressed even when there are fluctuations in the components forming the stepper motor 100A and in the assembled state. Furthermore, since the structure is simple, noise reduction is achieved without increasing costs. Moreover, since the projection height of the projection 700 towards the side of the rotor 400 is greater than the block length of the helical spring 800, the helical spring 800 is not compressed to its compression height, for example, when...Unforeseen large forces act on the rotor 400, causing it to move towards the front plate 210 and for the end face of the rotor component 402 to contact the end face of the extensions 701 of the projection 700. Therefore, damage to the coil spring 800 can be prevented.

[0035] Furthermore, a plurality of extensions 701 are formed on the end face of the projection 700, such that the end face against which the rotor component 402 rests is not a ring-shaped plane extending over the entire circumference. Therefore, the maximum height dimension of the projection 700 can be precisely defined by the extensions, thus facilitating a more precise maximum height dimension and flatness of the end face of the projection 700. In addition, when the rotor component 402 slides against the projection 700 during rotation, the contact area can be reduced, thereby aiming to reduce friction. With regard to friction reduction, the extensions 701 can be curved so that they are in point contact or a near-point contact with the rotor component 402. [2] Second embodiment

[0036] Next, we will use the following as an example: Fig. 4 to Fig. Section 6 describes a stepper motor 100B according to a second embodiment of the present invention. The stepper motor 100B of the second embodiment differs from the stepper motor 100A of the first embodiment above in the connecting means of the front stator arrangement 200 and the rear stator arrangement 300, as well as in the design of the front plate. In the stepper motor 100B of the second embodiment, the respective stator arrangements 200, 300, and the rotor 400 have the same design as in the first embodiment, with identical components being designated with the same reference numerals, and their description being omitted or simplified. The aforementioned differences are explained below. The rotor 400 of the second embodiment consists of the rotor component 402, on the outer circumferential surface of which a rotor magnet (not shown) is provided, and the shaft 403, which passes through and is fastened to the center of the axis of the rotor component 402.

[0037] The connecting element of the front stator arrangement 200 and the end stator arrangement 300 in the second embodiment is a resin mold, wherein an end plate 350 is also formed simultaneously at the time of resin molding. During resin molding, as in Fig. Figure 6 shows a state in which the coil former 230, wound with coils 231, is received on the inside, and furthermore the pole teeth 223 of the outer yoke 220 and the pole teeth 243 of the inner yoke 240 engage each other in specific gaps between them, the respective stator arrangements 200, 300 are inserted into a casting mold (not shown) such that the bottom surface sections 221 of the outer yokes 220 overlap coaxially in a manner adapted to one another. That is, in the second embodiment, in contrast to the first embodiment, the outer yokes 220 are arranged on the axial inside and the inner yokes 240 on the axial outside.

[0038] Next, the stator assemblies 200 and 300 are formed in one piece from resin by injecting thermoplastic resin into the mold above, filling the spaces between the pole teeth 223 and 243 with resin. Simultaneously, the disc-shaped end plate 350 is formed from resin on the outside of the end stator assembly 300.

[0039] After this resin forming, the front plate 250 is placed on the outer surface of the inner yoke 240 of the front stator assembly 200 of the molded body removed from the casting mold. Then, as described in Fig. 5 and Fig. Figure 6 shows that the edge of the cylinder section 222 of the outer yoke 220 in the front stator arrangement 200 is connected by crimping in notches 252, which are arranged at three locations on the outer circumferential edge of the front plate 250 and are spaced substantially equally apart, thus achieving the stepper motor 100B of the second embodiment. There is no limitation to three locations for the crimping connection using the notches 252; at least two locations are sufficient.

[0040] Next, the front panel 250 of the second embodiment will be explained. As in Fig. 4 and Fig. As shown in Figure 5, the front plate 250 has as its main component a disk section 251 positioned coaxially with the front stator arrangement 200 and covering the front stator arrangement 200, wherein flange sections 253 extending radially outwards from the disk section 251 are formed on both sides of the disk section 251. The flange sections 253 extend in Fig. 5 approximately from the edge section of the area of ​​the lower half of the disc section 251 obliquely upwards, the width being uniform and the front end being formed in a semicircular arc.

[0041] As in Fig. As shown in Figure 6, a bearing bore 255 for the shaft 403 is formed in the center of the disc section 251. A bearing bore 355 for the shaft 403 is also formed in the end plate 350. As in the first embodiment, the shaft 403 passes through the bearing bores 255, 355 formed in the front plate 250 and the end plate 350 and is held freely rotatable by sliding in direct contact with the inner circumferential surfaces 255a, 355a of the bearing bores 255, 355.

[0042] In Fig. 4 and Fig. In the upper section of the disk section 251, a connection block 256 is formed integrally. As in the first embodiment, four axially extending connection pins 214 are embedded in the connection block 256. Furthermore, axially extending positioning pins 259 are formed integrally in the base section of the respective flange sections 253 with respect to the disk section 251 and below the connection block 256. Three positioning pins 259 are positioned circumferentially at intervals of approximately 90 degrees, although the number is not limited. Additionally, pairs of fastening pins 258 are attached vertically near the front end sections of the flange sections 253, projecting axially. The fastening pins 258, like those of the first embodiment, are essentially U-shaped metal components that are pressed into holes provided in the flange sections 253.The fastening pins 258 are to form a line through the center of the shaft 403 and the center point of the terminal block 256 (dashed two-dotted line in . Fig. 5) arranged essentially symmetrically along the axis of symmetry.

[0043] The connecting pins 214, the mounting pins 258 and the positioning pins 259 are used when attaching the stepper motor 100B to the in Fig. The circuit board 600 shown in Figure 6 is used. The circuit board 600 has a positioning hole 606, contact holes 602, and pin mounting holes 604, and also a through-hole 607 for the shaft 403. With the stepper motor 100B, the front panel 250 is fitted to the circuit board 600 in a state where the shaft 403 is passed through the through-hole 607, the positioning pin 259 is inserted into the positioning hole 606, the connection pins 214 are inserted into the contact holes 602, and the mounting pins 258 are inserted into the pin mounting holes 604. The stepper motor 100B is then attached to the circuit board 600 by soldering a copper foil 603, which forms a conductor pattern in the vicinity of the contact holes 602, and the connecting pins 214, and a copper foil 605 in the vicinity of the pin mounting holes 604 and the mounting pins 258.

[0044] In the stepper motor 100B, a total of three points are soldered to the circuit board 600: the points where the four connecting pins 214 are attached to the terminal block 256, and the two points where the mounting pins 258 are attached to the respective flange sections 253. This results in a well-balanced mounting structure without placing excessive stress on the connecting pin sections 214, thereby improving the mounting stability of the stepper motor 100B. While the front panel 250 of the second embodiment does not include the extensions 216 shown in the first embodiment, it can include such extensions, which can be fitted and secured in the through-hole 607 of the front panel 250, further improving the mounting stability.

[0045] The second embodiment of the 100B stepper motor also uses a structure that suppresses axial play in the 400 rotor. That is, as in Fig.As shown in Figure 6, an annular projection 710 is formed in one piece on the inner surface of the front plate 250 in the vicinity of the bearing bore 255. Inside this projection 710, a helical spring 800 is arranged in the compressed state between the front plate 250 and the rotor component 402 when mounted on the shaft 403. Washers 901 and 902, made of a material with good sliding properties such as resin, are arranged between the helical spring 800 and the front plate 250, and between the helical spring 800 and the rotor component 402. A similar washer 903 is also arranged between the rotor component 402 and the end plate 350. The rotor component 402 is biased towards the end plate 350 by the helical spring 800 and is constantly pressed against the end plate 350 by the washer 903.

[0046] On the projection 710, as in the first embodiment on the front end edge section, a plurality (in the present case three pieces) of extensions 711 are formed at equal intervals from each other, the maximum height of which is set greater than the block length of the coil spring 800.

[0047] In the second embodiment, as in the first embodiment, such a design ensures that axial play of the rotor 400 is absorbed, thereby suppressing the generation of noise, and that, due to the simple structure, an increase in costs is suppressed. Furthermore, by ensuring that the height of the projection 710, which accommodates the helical spring 800 and includes the extensions 711, is greater than the block length of the helical spring 800, damage to the helical spring 800 is also prevented. [Industrial applicability]

[0048] The present invention can be used for a stepper motor. [List of reference symbols] 100A, 100B stepper motor 200 front stator assembly (stator) 210, 250 Front panel 213, 256 Terminal block 214 Connecting pin 218, 258 Fastening pin 231 coil 253 Flange section 255, 355 bearing bore 255a, 355a Inner circumferential surface of the bearing bore (support section) 300 End-side stator arrangement (stator) 310, 350 End plate (other component) 400 Rotor 403 wave 600 Printed circuit board (mounting component) 700, 710 lead 701, 711 Extensions of the protrusion 800 coil spring H Height of the ledge

Claims

[1] Stepper motor, characterized by that this a rotor having a shaft, a stator arranged adjacent to the rotor, and a plate arranged opposite one axial end of the rotor and having a support portion supporting the shaft, wherein the plate has an annular projection formed integrally on the surface facing the rotor, protruding towards the rotor side and surrounding the shaft, wherein a coil spring is provided within the projection, which is supported between the plate and the rotor when placed on the shaft, biases the rotor in the axial direction toward the other end side and elastically presses the rotor against other components, and a plurality of projections are formed on the end surface of the projection such that the projections surround the coil spring. [2] Stepper motor according to claim 1, characterized bythat the axial height of the projection protruding towards the rotor side is greater than the block length of the coil spring. [3] Stepper motor according to claim 1 or 2, characterized by that the plate comprises a terminal block on which terminal pins are provided to which the coils of the stator are connected, and a flange portion, wherein fastening pins for fastening to a fastening component are provided on the flange portion. [4] Stepper motor according to claim 3, characterized by a shape in which the flange portions of the plate extend radially, wherein a plurality of these flange portions are formed. [5] Stepper motor according to one of claims 1 to 4, characterized by that the other components are a plate arranged on the axially other end side of the rotor. [6] Stepper motor according to one of claims 1 to 5, characterized bythat the coil spring protrudes from the end face of the projection's extensions and presses the rotor against the other components. [7] Stepper motor according to one of claims 1 to 6, characterized by that the coil spring presses the rotor, with the coil spring resting with its ends on the plate and the rotor.

Images