WO2020251146A1 - Hollow shaft motor - Google Patents

Hollow shaft motor Download PDF

Info

Publication number
WO2020251146A1
WO2020251146A1 PCT/KR2020/004389 KR2020004389W WO2020251146A1 WO 2020251146 A1 WO2020251146 A1 WO 2020251146A1 KR 2020004389 W KR2020004389 W KR 2020004389W WO 2020251146 A1 WO2020251146 A1 WO 2020251146A1
Authority
WO
WIPO (PCT)
Prior art keywords
hollow shaft
coupled
housing
motor
motor housing
Prior art date
Application number
PCT/KR2020/004389
Other languages
French (fr)
Inventor
Ok Yun Kim
Kea Ho Lee
Haeng Chul Sin
Gwan Seon JEONG
Original Assignee
Tamas Co., Ltd.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Tamas Co., Ltd. filed Critical Tamas Co., Ltd.
Publication of WO2020251146A1 publication Critical patent/WO2020251146A1/en

Links

Images

Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K7/00—Arrangements for handling mechanical energy structurally associated with dynamo-electric machines, e.g. structural association with mechanical driving motors or auxiliary dynamo-electric machines
    • H02K7/003—Couplings; Details of shafts
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K7/00—Arrangements for handling mechanical energy structurally associated with dynamo-electric machines, e.g. structural association with mechanical driving motors or auxiliary dynamo-electric machines
    • H02K7/06—Means for converting reciprocating motion into rotary motion or vice versa
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C3/00—Shafts; Axles; Cranks; Eccentrics
    • F16C3/02—Shafts; Axles
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C35/00—Rigid support of bearing units; Housings, e.g. caps, covers
    • F16C35/04—Rigid support of bearing units; Housings, e.g. caps, covers in the case of ball or roller bearings
    • F16C35/06—Mounting or dismounting of ball or roller bearings; Fixing them onto shaft or in housing
    • F16C35/063—Fixing them on the shaft
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K1/00—Details of the magnetic circuit
    • H02K1/06—Details of the magnetic circuit characterised by the shape, form or construction
    • H02K1/22—Rotating parts of the magnetic circuit
    • H02K1/27—Rotor cores with permanent magnets
    • H02K1/2706—Inner rotors
    • H02K1/272—Inner rotors the magnetisation axis of the magnets being perpendicular to the rotor axis
    • H02K1/274—Inner rotors the magnetisation axis of the magnets being perpendicular to the rotor axis the rotor consisting of two or more circumferentially positioned magnets
    • H02K1/2753—Inner rotors the magnetisation axis of the magnets being perpendicular to the rotor axis the rotor consisting of two or more circumferentially positioned magnets the rotor consisting of magnets or groups of magnets arranged with alternating polarity
    • H02K1/278—Surface mounted magnets; Inset magnets
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K21/00—Synchronous motors having permanent magnets; Synchronous generators having permanent magnets
    • H02K21/12—Synchronous motors having permanent magnets; Synchronous generators having permanent magnets with stationary armatures and rotating magnets
    • H02K21/22—Synchronous motors having permanent magnets; Synchronous generators having permanent magnets with stationary armatures and rotating magnets with magnets rotating around the armatures, e.g. flywheel magnetos
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K5/00—Casings; Enclosures; Supports
    • H02K5/04—Casings or enclosures characterised by the shape, form or construction thereof
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K5/00—Casings; Enclosures; Supports
    • H02K5/04—Casings or enclosures characterised by the shape, form or construction thereof
    • H02K5/16—Means for supporting bearings, e.g. insulating supports or means for fitting bearings in the bearing-shields
    • H02K5/161—Means for supporting bearings, e.g. insulating supports or means for fitting bearings in the bearing-shields radially supporting the rotary shaft at both ends of the rotor
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K7/00—Arrangements for handling mechanical energy structurally associated with dynamo-electric machines, e.g. structural association with mechanical driving motors or auxiliary dynamo-electric machines
    • H02K7/08—Structural association with bearings
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K7/00—Arrangements for handling mechanical energy structurally associated with dynamo-electric machines, e.g. structural association with mechanical driving motors or auxiliary dynamo-electric machines
    • H02K7/08—Structural association with bearings
    • H02K7/086—Structural association with bearings radially supporting the rotor around a fixed spindle; radially supporting the rotor directly
    • H02K7/088—Structural association with bearings radially supporting the rotor around a fixed spindle; radially supporting the rotor directly radially supporting the rotor directly
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C2226/00—Joining parts; Fastening; Assembling or mounting parts
    • F16C2226/10—Force connections, e.g. clamping
    • F16C2226/12—Force connections, e.g. clamping by press-fit, e.g. plug-in
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C2380/00—Electrical apparatus
    • F16C2380/26—Dynamo-electric machines or combinations therewith, e.g. electro-motors and generators
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K7/00—Arrangements for handling mechanical energy structurally associated with dynamo-electric machines, e.g. structural association with mechanical driving motors or auxiliary dynamo-electric machines
    • H02K7/08—Structural association with bearings
    • H02K7/083—Structural association with bearings radially supporting the rotary shaft at both ends of the rotor

Definitions

  • the present invention relates to a motor. More specifically, the present invention relates to a motor adopting a bent hollow shaft and a novel motor housing structure to a hollow shaft motor used in an integrated brake system, thereby allowing the hollow shaft and motor housing to be produced by a pressing process, reducing manufacturing costs and improving assemblability and productivity.
  • a brake system In general, a brake system generates pressure in a master cylinder to amplify the force applied to a brake and provides the pressure to a module requiring braking.
  • a hollow shaft motor is used as an apparatus for generating pressure in a master cylinder. Such hollow shaft motor rotates a hollow shaft by the principle of a motor, and applies a screw inside the hollow shaft to use the principle of converting rotary motion into linear motion. The linear motion of the screw actuates a piston to generate or remove the pressure required in the master cylinder.
  • an integrated dynamic brake (IDB) system mainly used a motor with a hollow shaft. Since the hollow shaft of the motor needs to generate high pressure by a screw and a piston operating in the hollow shaft, a considerable axial load is imposed on bearings supporting the hollow shaft. In this regard, four-point contact ball bearings may be used to support the rotation of the hollow shaft.
  • Korean Patent Laid-open No. 10-2016-0001681 discloses a motor having a structure that can manufacture a hollow shaft and a motor housing by a pressing process. Here, however, since the motor housing has the lower side closed, the assembling operation is difficult, and it is difficult to install a four-point contact ball bearing.
  • Japanese Patent Laid-open No. 2000-56179 discloses a structure of fastening covers to an upper portion and a lower portion of a motor housing, respectively, by means of bolts. This structure increases manufacturing processes, and makes it difficult to maintain the air tightness between the motor housing and the cover.
  • Korean Patent Laid-open No. 10-2017-0006535 discloses a structure of opening the lower side of a motor housing and assembling a separate cover thereto, and the technique of manufacturing a motor housing by a pressing process such as deep drawing. According to the structure, a separate cover is assembled to the lower side of the motor housing to support bearings supporting a hollow shaft, thereby supporting the load imposed on the hollow shaft. Thus, the assemblability and productivity decrease.
  • the present invention was invented in order to solve the above-mentioned problems. It is an object of the present invention to provide a hollow shaft motor with a novel structure allowing a hollow shaft and a motor housing to be produced by a pressing process, thereby reducing manufacturing costs, and improving assemblability and productivity.
  • the hollow shaft motor comprises a motor housing 11 having a cylindrical shape; a drawing sleeve 12 coupled to an upper portion of the motor housing 11; a rear cover 15 coupled to a lower portion of the motor housing 11; a stator assembly 20 located in the motor housing 11 with a bus bar housing 24 coupled to an upper portion thereof; and a rotor assembly 30 located in the stator assembly 20 to rotate, comprising a hollow shaft 31, a rotor core 32 coupled to an outer circumference of the hollow shaft 31, and a plurality of magnets 33 attached to an outer circumference of the rotor core 32, wherein the drawing sleeve 12 comprises a disk-shaped disk part 121, and a cylindrical part 122 having a cylindrical shape downwardly extending from a central portion of the disk part 121, and the inside of the cylindrical part 122 comprises a central space 122A which is an open space penetrating from the upper portion to the lower portion.
  • the hollow shaft 31 comprises: a hollow shaft housing 311 having a cylindrical shape; an upper bearing coupling groove 312 formed in an upper portion of the hollow shaft housing 311; an upper stepped part 313 bent outwardly in an upper portion of the upper bearing coupling groove 312; a lower stepped part 314 formed in a lower portion of the upper bearing coupling groove 312; and a lower bearing supporting part 316 protruding to a lower portion of the hollow shaft housing 311.
  • an inner race of an upper bearing 13 is press-fitted to the upper bearing coupling groove 312.
  • an outer race of the upper bearing 13 may be supportedly coupled to an upper bearing supporting part 24C formed in an inner circumferential portion of the bus bar housing 24.
  • a lower protruding part 115 protruding downwardly to the center of a bottom part 114 may be formed in a lower portion of a body part 111 of the motor housing 11, a lower bearing coupling part 116 to which a lower bearing 14 is coupled may be formed in a space inside the lower protruding part 115, and a curved bent part 117 in which the bottom part 114 and the lower protruding part 115 are connected may be formed in an upper end portion of the lower bearing coupling part 116.
  • the curved bent part 117 may support an upper outer circumferential surface of the lower bearing 14.
  • a flange part 152 of the rear cover 15 may be coupled by a curling part 115A inwardly formed in the lower end of the lower protruding part 115.
  • the present invention allows a hollow shaft of a motor and a motor housing to be produced by a pressing process, thereby having the effects of reducing manufacturing costs, and improving assemblability and productivity.
  • Fig. 1 is a perspective view of a hollow shaft motor according to the present invention
  • Fig. 2 is an exploded perspective view of the hollow shaft motor according to the present invention.
  • Fig. 3 is a cross-sectional view taken along the A-A' direction of Fig. 1;
  • Fig. 4 is an exploded perspective view of a rotor assembly of the hollow shaft motor according to the present invention.
  • Fig. 5 is an exploded top perspective view of a drawing sleeve of the hollow shaft motor according to the present invention.
  • Fig. 6 is an exploded bottom perspective view of a rear cover of the hollow shaft motor according to the present invention.
  • Fig. 7 is a cross-sectional view of another embodiment of the rear cover taken along the A-A' direction of Fig. 1.
  • Fig. 1 is a perspective view of a hollow shaft motor 100 according to the present invention
  • Fig. 2 is an exploded perspective view of the hollow shaft motor 100 according to the present invention
  • Fig. 3 is a cross-sectional view taken along the A-A' direction of Fig. 1.
  • the hollow shaft motor 100 includes a screw shaft 10, a motor housing 11, a stator assembly 20 coupled to an inner side of the motor housing 11, and a rotor assembly 30 located in the stator assembly 20.
  • the screw shaft 10 has a lower end portion coupled to the hollow shaft 31 so as to rotate with the rotor assembly 30.
  • a ball nut 17 is coupled to an outer circumferential surface of the screw shaft 10, and the ball nut 17 moves up and down according to the rotation of the screw shaft 10, thereby generating or removing the pressure in the piston (not illustrated).
  • the motor housing 11 can be manufactured by a continuous process using pressing equipment such as a transfer mold.
  • the motor housing 11 has a body part 111 having a cylindrical shape whose upper portion and lower portion are open.
  • the part that is open to the upper side of the motor housing 11 is an inner space part 112, and a flange part 113 extending in the horizontal direction is formed around the inner space part.
  • a drawing sleeve 12 is coupled to the inner space part 112 so as to cover an upper portion of the inner space part 112.
  • a flange part 113 is coupled to a block (not illustrated) of a brake system.
  • a bottom part 114 horizontally extending towards the center is formed in a lower portion of the body part 111, and the lower end portion of the body part 111 may have a horizontal cross-section diameter reducing until reaching the bottom part 114.
  • a lower protruding part 115 protruding downwardly is formed in a central portion of the bottom part 114.
  • a lower bearing coupling part 116 to which the lower bearing 14 is coupled is formed in a space inside the lower protruding part 115.
  • a curved bent part 117 in which the bottom part 114 and the lower protruding part 115 are connected is formed in an upper end portion of the lower bearing coupling part 116.
  • the curved bent part 117 has a shape where a central portion of the bottom part 114 is bent so as to be connected to the lower protruding part 115, which allows the curved bent part 117 to support the upper circumferential surface of the lower bearing 14 so that the lower bearing 14 could be coupled more solidly and intensively.
  • the lower protruding part 115 has a structure wherein the material is bent and folded, to reinforce strength.
  • the lower bearing 14 is press-fitted and coupled to an inner surface of the lower protruding part 115, and the upper circumferential portion of the lower bearing 14 is supported by the curved bent part 117.
  • the curved bent part 117 is preferably bent and extended to the inside at a position the same as or higher than the bottom part 114, thereby stably supporting the lower bearing 14.
  • the lower circumferential portion of the lower bearing 14 is supported by a curling part 115A.
  • the flange part 152 of the rear cover 15 may be interposed between the curling part 115A and the lower circumferential portion of the lower bearing 14.
  • the lower circumferential portion of the lower bearing 14 may be directly supported by the curling part 115A.
  • the curling part 115A is formed by subjecting a lower distal portion of the lower protruding part 115 to a curling process by the press.
  • the drawing sleeve 12 is coupled to an upper portion of the inner space part 112, and at the same time, to an upper portion of the bus bar housing 24 of the stator assembly 20.
  • the drawing sleeve 12 comprises a disk-shaped disk part 121, and a cylindrical part 122 having a cylindrical shape downwardly extending from a central portion of the disk part 121, and the inside of the cylindrical part 122 comprises a central space 122A which is an open space penetrating from the upper portion to the lower portion.
  • the drawing sleeve 12 may form a metal board through continuous drawing processes.
  • the cylindrical part 122 is downwardly extended from a central portion of the disk part 121 of the drawing sleeve 12 so that the inner space thereof could form a central space 122A.
  • a ball nut 17 and a piston (not illustrated) for moving up and down by the rotation of the hollow shaft 31 and the screw shaft 10 are located inside the central space 122A.
  • a plurality of fitting protrusions 121A radially protruding are formed in the circumferential portion of the disk part 121 of the drawing sleeve 12.
  • Fitting grooves 112A are formed around the upper portion of the inner space part 112 of the motor housing 11 corresponding to the fitting protrusions 121A, so the fitting protrusion 121A could be fitted into and coupled to the fitting groove 112A.
  • a terminal space 121B is formed at one side of the disk part 121, allowing a terminal cover 25 to pass the terminal space 121B so that the bus bar terminal 26 could be connected to an external power source.
  • the outer race of the upper bearing 13 is supportedly coupled to the upper bearing supporting part 24C formed in the inner circumferential portion of the bus bar housing 24.
  • the inner race of the upper bearing 13 is supported by a bearing coupling groove 312 formed in the upper portion of the hollow shaft 31 to support the rotation of the hollow shaft 31.
  • the cylindrical part 122 of the drawing sleeve 12 is downwardly extended from a central space of the hollow shaft 31, allowing the hollow shaft 31 to be independently separated from the central space 122A inside the cylindrical part 122. Accordingly, a movement space of the piston (not illustrated) which moves up and down may be independently secured.
  • the lower bearing 14 supports the rotation of a lower bearing supporting part 316 formed in a lower end portion of the hollow shaft 31.
  • the lower bearing 14 is coupled to the lower bearing coupling part 116 formed in a lower end of the motor housing 11.
  • the rear cover 15 is coupled to a lower inner side of the lower protruding part 115 of the motor housing 11 to cover the lower portion of the lower protruding part 115.
  • the rear cover 15 is coupled and fixed to the lower protruding part 115 by a curling part 115A at a lower end of the lower protruding part 115.
  • a lock nut 16 is coupled to a lower end of the screw shaft 10.
  • the stator assembly 20 comprises a stator core 21 press-fitted and fixed to an inner side of the body part 111 of the motor housing 11, an upper insulator 22 coupled to an upper portion of the stator core 21, and a lower insulator 23 coupled to a lower portion of the stator core 21.
  • a coil (not illustrated) is wound around each insulator, and the coil is electrically connected to a bus bar (not illustrated) of a bus bar housing 24 coupled to an upper portion of the upper insulator 22.
  • the bus bar is electrically connected to a bus bar terminal 26 to supply power from an external power source.
  • the bus bar terminal 26 is surrounded and protected by a terminal cover 25.
  • the outer circumferential portion of the bus bar housing 24 is press-fitted and coupled to the upper portion of the inner space part 112 formed in an upper inner side of the body part 111 of the motor housing 11.
  • a plurality of coupling protrusions 24A protruding to an upper portion of the bus bar housing 24 are coupled in correspondence with coupling holes 121C of the drawing sleeve 12.
  • a plurality of fitting protrusions 24B protruding towards the outer circumference of the bus bar housing 24 are located at the same position with the same shape as the fitting protrusion 121A of the drawing sleeve 12, to be coupled to the fitting groove 112A of the motor housing 11.
  • Fig. 4 is an exploded perspective view of a rotor assembly of the hollow shaft motor according to the present invention.
  • the rotor assembly 30 of the present invention is located inside the stator assembly 20 to rotate.
  • the rotor assembly 30 comprises a hollow shaft 31, a rotor core 32 coupled to the outer circumference of the hollow shaft 31, a plurality of magnets 33 attached to an outer circumference of the rotor core 32, and a rotor can 34 coupled to an outer circumferential portion of the magnet 33.
  • the hollow shaft 31 has a hollow shaft housing 311 having a cylindrical shape.
  • the rotor core 32 is coupled to an outer circumferential surface of the hollow shaft housing 311.
  • a plurality of magnets 33 are attached to an outer circumferential surface of the rotor core 32.
  • the rotor core 32 may be omitted, and the plurality of magnets 33 may be directly attached to the outer circumferential surface of the hollow shaft housing 311.
  • the rotor can 34 be press-fitted and coupled to the outer circumferential surface of the magnet 33.
  • An upper bearing coupling groove 312 having a slightly smaller diameter than the hollow shaft housing 311 is formed in an upper portion of the hollow shaft housing 311.
  • the rotation of the inner race of the upper bearing 13 is supported by the upper bearing coupling groove 312.
  • An upper stepped part 313 bent outwardly is formed at an upper portion of the upper bearing coupling groove 312, and a lower stepped part 314 is formed at a lower portion of the upper bearing coupling groove 312, so as to have a groove shape for coupling the inner race of the upper bearing 13 to the upper bearing coupling groove 312.
  • the upper stepped part 313 may be formed by a curling process during the press molding process.
  • a reduced diameter part 315 which is a part bent and connected so that the diameter thereof is gradually reduced to the diameter of the lower bearing supporting part 316 is formed at a lower end portion of the hollow shaft housing 311. The rotation of the lower bearing supporting part 316 protruding from the reduced diameter part is supported by the lower bearing 14.
  • Fig. 5 is an exploded top perspective view of a drawing sleeve 12 of the hollow shaft motor 100 according to the present invention.
  • the drawing sleeve 12 is coupled to the inner space part 112 of the motor housing 11 of the present invention.
  • a plurality of fitting protrusions 121A formed in the outer circumference of the disk part 121 of the drawing sleeve 12 are fitted into and coupled to the fitting grooves 112A formed around the inner space part 112 of the motor housing 11.
  • a terminal space 121B through which a terminal cover 25 having a bus bar terminal 26 penetrates is formed at one side of the disk part 121.
  • a cylindrical part 122 of the drawing sleeve 12 is extended downwardly, and a screw shaft 10 and a ball nut 17 for moving the piston (not illustrated) up and down are located in the central space 122A therein.
  • Fig. 6 is an exploded bottom perspective view of a rear cover 15 of the hollow shaft motor 100 according to the present invention.
  • the rear cover 15 is coupled to the inner side of the lower protruding part 115 at a lower end portion of the body part 111 of the motor housing 11.
  • the rear cover 15 comprises a cup-shaped cover part 151, and a flange part 152 extended in the circumferential direction from an upper end portion of the cover part 151.
  • the flange part 152 is located inside the lower end of the lower protruding part 115, and at the same time, coupled to be in contact with a lower portion of the outer race of the lower bearing 14.
  • a curling part 115A formed by curling a lower end of the lower protruding part 115 solidly couples the flange part 152 at a lower end of the flange part 152. This structure provides a more solid coupling structure between the rear cover 15 and the lower protruding part 115.
  • FIG. 7 is a cross-sectional view showing another embodiment of the rear cover 15' taken along the A-A' direction of Fig. 1.
  • a rear cover 15' according to another embodiment of the present invention comprises a cup-shaped cover part 151' and a side wall part 152' upwardly extended from the cover part 151'.
  • the inner circumferential portion of the side wall part 152' is press-fitted and coupled to the outer circumferential portion of the lower protruding part 115. This structure allows the coupling structure to be much simpler, thereby saving processing costs.

Abstract

The hollow shaft motor according to the present invention comprises: a motor housing 11 having a cylindrical shape; a drawing sleeve 12 coupled to an upper portion of the motor housing 11; a rear cover 15 coupled to a lower portion of the motor housing 11; a stator assembly 20 located in the motor housing 11 with a bus bar housing 24 coupled to an upper portion thereof; and a rotor assembly 30 located in the stator assembly 20 to rotate, comprising a hollow shaft 31, a rotor core 32 coupled to an outer circumference of the hollow shaft 31, and a plurality of magnets 33 attached to an outer circumference of the rotor core 32, wherein the drawing sleeve 12 comprises a disk-shaped disk part 121, and a cylindrical part 122 having a cylindrical shape downwardly extending from a central portion of the disk part 121, and the inside of the cylindrical part 122 comprises a central space 122A which is an open space penetrating from the upper portion to the lower portion.

Description

HOLLOW SHAFT MOTOR
The present invention relates to a motor. More specifically, the present invention relates to a motor adopting a bent hollow shaft and a novel motor housing structure to a hollow shaft motor used in an integrated brake system, thereby allowing the hollow shaft and motor housing to be produced by a pressing process, reducing manufacturing costs and improving assemblability and productivity.
In general, a brake system generates pressure in a master cylinder to amplify the force applied to a brake and provides the pressure to a module requiring braking. A hollow shaft motor is used as an apparatus for generating pressure in a master cylinder. Such hollow shaft motor rotates a hollow shaft by the principle of a motor, and applies a screw inside the hollow shaft to use the principle of converting rotary motion into linear motion. The linear motion of the screw actuates a piston to generate or remove the pressure required in the master cylinder.
Recently, an integrated dynamic brake (IDB) system mainly used a motor with a hollow shaft. Since the hollow shaft of the motor needs to generate high pressure by a screw and a piston operating in the hollow shaft, a considerable axial load is imposed on bearings supporting the hollow shaft. In this regard, four-point contact ball bearings may be used to support the rotation of the hollow shaft.
Korean Patent Laid-open No. 10-2016-0001681 discloses a motor having a structure that can manufacture a hollow shaft and a motor housing by a pressing process. Here, however, since the motor housing has the lower side closed, the assembling operation is difficult, and it is difficult to install a four-point contact ball bearing.
Japanese Patent Laid-open No. 2000-56179 discloses a structure of fastening covers to an upper portion and a lower portion of a motor housing, respectively, by means of bolts. This structure increases manufacturing processes, and makes it difficult to maintain the air tightness between the motor housing and the cover.
Korean Patent Laid-open No. 10-2017-0006535 discloses a structure of opening the lower side of a motor housing and assembling a separate cover thereto, and the technique of manufacturing a motor housing by a pressing process such as deep drawing. According to the structure, a separate cover is assembled to the lower side of the motor housing to support bearings supporting a hollow shaft, thereby supporting the load imposed on the hollow shaft. Thus, the assemblability and productivity decrease.
The present invention was invented in order to solve the above-mentioned problems. It is an object of the present invention to provide a hollow shaft motor with a novel structure allowing a hollow shaft and a motor housing to be produced by a pressing process, thereby reducing manufacturing costs, and improving assemblability and productivity.
The object above and other objects inferred therein can be easily achieved by the present invention explained below.
The hollow shaft motor according to the present invention comprises a motor housing 11 having a cylindrical shape; a drawing sleeve 12 coupled to an upper portion of the motor housing 11; a rear cover 15 coupled to a lower portion of the motor housing 11; a stator assembly 20 located in the motor housing 11 with a bus bar housing 24 coupled to an upper portion thereof; and a rotor assembly 30 located in the stator assembly 20 to rotate, comprising a hollow shaft 31, a rotor core 32 coupled to an outer circumference of the hollow shaft 31, and a plurality of magnets 33 attached to an outer circumference of the rotor core 32, wherein the drawing sleeve 12 comprises a disk-shaped disk part 121, and a cylindrical part 122 having a cylindrical shape downwardly extending from a central portion of the disk part 121, and the inside of the cylindrical part 122 comprises a central space 122A which is an open space penetrating from the upper portion to the lower portion.
In the present invention, preferably, the hollow shaft 31 comprises: a hollow shaft housing 311 having a cylindrical shape; an upper bearing coupling groove 312 formed in an upper portion of the hollow shaft housing 311; an upper stepped part 313 bent outwardly in an upper portion of the upper bearing coupling groove 312; a lower stepped part 314 formed in a lower portion of the upper bearing coupling groove 312; and a lower bearing supporting part 316 protruding to a lower portion of the hollow shaft housing 311.
Preferably, an inner race of an upper bearing 13 is press-fitted to the upper bearing coupling groove 312.
In the present invention, an outer race of the upper bearing 13 may be supportedly coupled to an upper bearing supporting part 24C formed in an inner circumferential portion of the bus bar housing 24.
In the present invention, a lower protruding part 115 protruding downwardly to the center of a bottom part 114 may be formed in a lower portion of a body part 111 of the motor housing 11, a lower bearing coupling part 116 to which a lower bearing 14 is coupled may be formed in a space inside the lower protruding part 115, and a curved bent part 117 in which the bottom part 114 and the lower protruding part 115 are connected may be formed in an upper end portion of the lower bearing coupling part 116.
In the present invention, preferably, the curved bent part 117 may support an upper outer circumferential surface of the lower bearing 14.
In the present invention, preferably, a flange part 152 of the rear cover 15 may be coupled by a curling part 115A inwardly formed in the lower end of the lower protruding part 115.
The present invention allows a hollow shaft of a motor and a motor housing to be produced by a pressing process, thereby having the effects of reducing manufacturing costs, and improving assemblability and productivity.
Fig. 1 is a perspective view of a hollow shaft motor according to the present invention;
Fig. 2 is an exploded perspective view of the hollow shaft motor according to the present invention;
Fig. 3 is a cross-sectional view taken along the A-A' direction of Fig. 1;
Fig. 4 is an exploded perspective view of a rotor assembly of the hollow shaft motor according to the present invention;
Fig. 5 is an exploded top perspective view of a drawing sleeve of the hollow shaft motor according to the present invention;
Fig. 6 is an exploded bottom perspective view of a rear cover of the hollow shaft motor according to the present invention; and
Fig. 7 is a cross-sectional view of another embodiment of the rear cover taken along the A-A' direction of Fig. 1.
Hereinafter, the present invention will be explained in detail with reference to the accompanying drawings.
Fig. 1 is a perspective view of a hollow shaft motor 100 according to the present invention, Fig. 2 is an exploded perspective view of the hollow shaft motor 100 according to the present invention, and Fig. 3 is a cross-sectional view taken along the A-A' direction of Fig. 1.
As illustrated in Figs. 1 to 3, the hollow shaft motor 100 according to the present invention includes a screw shaft 10, a motor housing 11, a stator assembly 20 coupled to an inner side of the motor housing 11, and a rotor assembly 30 located in the stator assembly 20.
The screw shaft 10 has a lower end portion coupled to the hollow shaft 31 so as to rotate with the rotor assembly 30. A ball nut 17 is coupled to an outer circumferential surface of the screw shaft 10, and the ball nut 17 moves up and down according to the rotation of the screw shaft 10, thereby generating or removing the pressure in the piston (not illustrated).
The motor housing 11 can be manufactured by a continuous process using pressing equipment such as a transfer mold. The motor housing 11 has a body part 111 having a cylindrical shape whose upper portion and lower portion are open. The part that is open to the upper side of the motor housing 11 is an inner space part 112, and a flange part 113 extending in the horizontal direction is formed around the inner space part. A drawing sleeve 12 is coupled to the inner space part 112 so as to cover an upper portion of the inner space part 112. A flange part 113 is coupled to a block (not illustrated) of a brake system.
A bottom part 114 horizontally extending towards the center is formed in a lower portion of the body part 111, and the lower end portion of the body part 111 may have a horizontal cross-section diameter reducing until reaching the bottom part 114. A lower protruding part 115 protruding downwardly is formed in a central portion of the bottom part 114. A lower bearing coupling part 116 to which the lower bearing 14 is coupled is formed in a space inside the lower protruding part 115. A curved bent part 117 in which the bottom part 114 and the lower protruding part 115 are connected is formed in an upper end portion of the lower bearing coupling part 116. In other words, the curved bent part 117 has a shape where a central portion of the bottom part 114 is bent so as to be connected to the lower protruding part 115, which allows the curved bent part 117 to support the upper circumferential surface of the lower bearing 14 so that the lower bearing 14 could be coupled more solidly and intensively.
More specifically, the lower protruding part 115 has a structure wherein the material is bent and folded, to reinforce strength. Thus, when a great load is imposed on a lower bearing 14, the structure can help supporting the load. The lower bearing 14 is press-fitted and coupled to an inner surface of the lower protruding part 115, and the upper circumferential portion of the lower bearing 14 is supported by the curved bent part 117. The curved bent part 117 is preferably bent and extended to the inside at a position the same as or higher than the bottom part 114, thereby stably supporting the lower bearing 14.
The lower circumferential portion of the lower bearing 14 is supported by a curling part 115A. As illustrated in Fig. 3, the flange part 152 of the rear cover 15 may be interposed between the curling part 115A and the lower circumferential portion of the lower bearing 14. Also, as illustrated in Fig. 7, the lower circumferential portion of the lower bearing 14 may be directly supported by the curling part 115A. The curling part 115A is formed by subjecting a lower distal portion of the lower protruding part 115 to a curling process by the press.
The drawing sleeve 12 is coupled to an upper portion of the inner space part 112, and at the same time, to an upper portion of the bus bar housing 24 of the stator assembly 20. The drawing sleeve 12 comprises a disk-shaped disk part 121, and a cylindrical part 122 having a cylindrical shape downwardly extending from a central portion of the disk part 121, and the inside of the cylindrical part 122 comprises a central space 122A which is an open space penetrating from the upper portion to the lower portion. The drawing sleeve 12 may form a metal board through continuous drawing processes. The cylindrical part 122 is downwardly extended from a central portion of the disk part 121 of the drawing sleeve 12 so that the inner space thereof could form a central space 122A. A ball nut 17 and a piston (not illustrated) for moving up and down by the rotation of the hollow shaft 31 and the screw shaft 10 are located inside the central space 122A.
A plurality of fitting protrusions 121A radially protruding are formed in the circumferential portion of the disk part 121 of the drawing sleeve 12. Fitting grooves 112A are formed around the upper portion of the inner space part 112 of the motor housing 11 corresponding to the fitting protrusions 121A, so the fitting protrusion 121A could be fitted into and coupled to the fitting groove 112A. A terminal space 121B is formed at one side of the disk part 121, allowing a terminal cover 25 to pass the terminal space 121B so that the bus bar terminal 26 could be connected to an external power source.
The outer race of the upper bearing 13 is supportedly coupled to the upper bearing supporting part 24C formed in the inner circumferential portion of the bus bar housing 24. The inner race of the upper bearing 13 is supported by a bearing coupling groove 312 formed in the upper portion of the hollow shaft 31 to support the rotation of the hollow shaft 31. The cylindrical part 122 of the drawing sleeve 12 is downwardly extended from a central space of the hollow shaft 31, allowing the hollow shaft 31 to be independently separated from the central space 122A inside the cylindrical part 122. Accordingly, a movement space of the piston (not illustrated) which moves up and down may be independently secured.
The lower bearing 14 supports the rotation of a lower bearing supporting part 316 formed in a lower end portion of the hollow shaft 31. The lower bearing 14 is coupled to the lower bearing coupling part 116 formed in a lower end of the motor housing 11.
As illustrated in Fig. 3, the rear cover 15 is coupled to a lower inner side of the lower protruding part 115 of the motor housing 11 to cover the lower portion of the lower protruding part 115. The rear cover 15 is coupled and fixed to the lower protruding part 115 by a curling part 115A at a lower end of the lower protruding part 115. A lock nut 16 is coupled to a lower end of the screw shaft 10.
The stator assembly 20 comprises a stator core 21 press-fitted and fixed to an inner side of the body part 111 of the motor housing 11, an upper insulator 22 coupled to an upper portion of the stator core 21, and a lower insulator 23 coupled to a lower portion of the stator core 21. A coil (not illustrated) is wound around each insulator, and the coil is electrically connected to a bus bar (not illustrated) of a bus bar housing 24 coupled to an upper portion of the upper insulator 22. The bus bar is electrically connected to a bus bar terminal 26 to supply power from an external power source. The bus bar terminal 26 is surrounded and protected by a terminal cover 25.
The outer circumferential portion of the bus bar housing 24 is press-fitted and coupled to the upper portion of the inner space part 112 formed in an upper inner side of the body part 111 of the motor housing 11. A plurality of coupling protrusions 24A protruding to an upper portion of the bus bar housing 24 are coupled in correspondence with coupling holes 121C of the drawing sleeve 12. A plurality of fitting protrusions 24B protruding towards the outer circumference of the bus bar housing 24 are located at the same position with the same shape as the fitting protrusion 121A of the drawing sleeve 12, to be coupled to the fitting groove 112A of the motor housing 11.
Fig. 4 is an exploded perspective view of a rotor assembly of the hollow shaft motor according to the present invention. Referring to Figs. 3 and 4 together, the rotor assembly 30 of the present invention is located inside the stator assembly 20 to rotate. To this end, the rotor assembly 30 comprises a hollow shaft 31, a rotor core 32 coupled to the outer circumference of the hollow shaft 31, a plurality of magnets 33 attached to an outer circumference of the rotor core 32, and a rotor can 34 coupled to an outer circumferential portion of the magnet 33.
The hollow shaft 31 has a hollow shaft housing 311 having a cylindrical shape. The rotor core 32 is coupled to an outer circumferential surface of the hollow shaft housing 311. A plurality of magnets 33 are attached to an outer circumferential surface of the rotor core 32. As needed, the rotor core 32 may be omitted, and the plurality of magnets 33 may be directly attached to the outer circumferential surface of the hollow shaft housing 311. The rotor can 34 be press-fitted and coupled to the outer circumferential surface of the magnet 33.
An upper bearing coupling groove 312 having a slightly smaller diameter than the hollow shaft housing 311 is formed in an upper portion of the hollow shaft housing 311. The rotation of the inner race of the upper bearing 13 is supported by the upper bearing coupling groove 312. An upper stepped part 313 bent outwardly is formed at an upper portion of the upper bearing coupling groove 312, and a lower stepped part 314 is formed at a lower portion of the upper bearing coupling groove 312, so as to have a groove shape for coupling the inner race of the upper bearing 13 to the upper bearing coupling groove 312. The upper stepped part 313 may be formed by a curling process during the press molding process.
A reduced diameter part 315 which is a part bent and connected so that the diameter thereof is gradually reduced to the diameter of the lower bearing supporting part 316 is formed at a lower end portion of the hollow shaft housing 311. The rotation of the lower bearing supporting part 316 protruding from the reduced diameter part is supported by the lower bearing 14.
Fig. 5 is an exploded top perspective view of a drawing sleeve 12 of the hollow shaft motor 100 according to the present invention. Referring to Fig. 5, the drawing sleeve 12 is coupled to the inner space part 112 of the motor housing 11 of the present invention. A plurality of fitting protrusions 121A formed in the outer circumference of the disk part 121 of the drawing sleeve 12 are fitted into and coupled to the fitting grooves 112A formed around the inner space part 112 of the motor housing 11. A terminal space 121B through which a terminal cover 25 having a bus bar terminal 26 penetrates is formed at one side of the disk part 121. A cylindrical part 122 of the drawing sleeve 12 is extended downwardly, and a screw shaft 10 and a ball nut 17 for moving the piston (not illustrated) up and down are located in the central space 122A therein.
Fig. 6 is an exploded bottom perspective view of a rear cover 15 of the hollow shaft motor 100 according to the present invention. As illustrated in Fig. 6, the rear cover 15 is coupled to the inner side of the lower protruding part 115 at a lower end portion of the body part 111 of the motor housing 11. The rear cover 15 comprises a cup-shaped cover part 151, and a flange part 152 extended in the circumferential direction from an upper end portion of the cover part 151. The flange part 152 is located inside the lower end of the lower protruding part 115, and at the same time, coupled to be in contact with a lower portion of the outer race of the lower bearing 14. Additionally, a curling part 115A formed by curling a lower end of the lower protruding part 115 solidly couples the flange part 152 at a lower end of the flange part 152. This structure provides a more solid coupling structure between the rear cover 15 and the lower protruding part 115.
Fig. 7 is a cross-sectional view showing another embodiment of the rear cover 15' taken along the A-A' direction of Fig. 1. A rear cover 15' according to another embodiment of the present invention comprises a cup-shaped cover part 151' and a side wall part 152' upwardly extended from the cover part 151'. The inner circumferential portion of the side wall part 152' is press-fitted and coupled to the outer circumferential portion of the lower protruding part 115. This structure allows the coupling structure to be much simpler, thereby saving processing costs.
The detailed description of the present invention described as above simply explains examples for understanding the present invention, but does not intend to limit the scope of the present invention. The scope of the present invention is defined by the accompanying claims. Additionally, it should be construed that simple modifications or changes of the present invention fall within the scope of the present invention.

Claims (6)

  1. A hollow shaft motor, comprising:
    a motor housing 11 having a cylindrical shape;
    a drawing sleeve 12 coupled to an upper portion of the motor housing 11;
    a rear cover 15 coupled to a lower portion of the motor housing 11;
    a stator assembly 20 located in the motor housing 11 with a bus bar housing 24 coupled to an upper portion thereof; and
    a rotor assembly 30 located in the stator assembly 20 to rotate, comprising a hollow shaft 31, a rotor core 32 coupled to an outer circumference of the hollow shaft 31, and a plurality of magnets 33 attached to an outer circumference of the rotor core 32,
    wherein the drawing sleeve 12 comprises a disk-shaped disk part 121, and a cylindrical part 122 having a cylindrical shape downwardly extending from a central portion of the disk part 121, and the inside of the cylindrical part 122 comprises a central space 122A which is an open space penetrating from the upper portion to the lower portion.
  2. The hollow shaft motor of claim 1, wherein the hollow shaft 31 comprises: a hollow shaft housing 311 having a cylindrical shape; an upper bearing coupling groove 312 formed in an upper portion of the hollow shaft housing 311; an upper stepped part 313 bent outwardly in an upper portion of the upper bearing coupling groove 312; a lower stepped part 314 formed in a lower portion of the upper bearing coupling groove 312; and a lower bearing supporting part 316 protruding to a lower portion of the hollow shaft housing 311, wherein an inner race of an upper bearing 13 is press-fitted to the upper bearing coupling groove 312.
  3. The hollow shaft motor of claim 2, wherein an outer race of the upper bearing 13 is supportedly coupled to an upper bearing supporting part 24C formed in an inner circumferential portion of the bus bar housing 24.
  4. The hollow shaft motor of claim 1, wherein a lower protruding part 115 protruding downwardly to the center of a bottom part 114 is formed in a lower portion of the body part 111 of the motor housing 11, a lower bearing coupling part 116 to which a lower bearing 14 is coupled is formed in a space inside the lower protruding part 115, and a curved bent part 117 in which the bottom part 114 and the lower protruding part 115 are connected is formed in an upper end portion of the lower bearing coupling part 116.
  5. The hollow shaft motor of claim 4, wherein the curved bent part 117 supports an upper outer circumferential surface of the lower bearing 14.
  6. The hollow shaft motor of claim 4, wherein a flange part 152 of the rear cover 15 is coupled by a curling part 115A inwardly formed in a lower end of the lower protruding part 115.
PCT/KR2020/004389 2019-06-13 2020-03-31 Hollow shaft motor WO2020251146A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
KR10-2019-0069913 2019-06-13
KR1020190069913A KR102155450B1 (en) 2019-06-13 2019-06-13 Hollow Shaft Motor

Publications (1)

Publication Number Publication Date
WO2020251146A1 true WO2020251146A1 (en) 2020-12-17

Family

ID=72472550

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/KR2020/004389 WO2020251146A1 (en) 2019-06-13 2020-03-31 Hollow shaft motor

Country Status (2)

Country Link
KR (1) KR102155450B1 (en)
WO (1) WO2020251146A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102021102500A1 (en) 2021-02-03 2022-08-04 Nidec Motors & Actuators (Germany) Gmbh Electric motor with deep-drawn motor housing

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20230149963A (en) * 2022-04-21 2023-10-30 엘지이노텍 주식회사 Motor
KR102575324B1 (en) 2023-03-30 2023-09-07 디와이오토 주식회사 Hollow shaft motor provided with improved rotational axis separation prevention structure

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2013162730A (en) * 2012-02-08 2013-08-19 Nsk Ltd Rotary electric machine
KR20140003674A (en) * 2012-06-22 2014-01-10 엘지이노텍 주식회사 Motor
KR20160001681A (en) * 2014-06-27 2016-01-06 로베르트 보쉬 게엠베하 Pressure generator for a hydraulic vehicle brake system
KR20160082053A (en) * 2014-12-30 2016-07-08 엘지이노텍 주식회사 Motor
KR20170011142A (en) * 2015-07-21 2017-02-02 엘지이노텍 주식회사 Housing of motor, Motor and Stabilizer apparatus having the same
KR101917961B1 (en) * 2017-09-26 2018-11-13 (주)타마스 Electronic Brake System with Ball Screw

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2013162730A (en) * 2012-02-08 2013-08-19 Nsk Ltd Rotary electric machine
KR20140003674A (en) * 2012-06-22 2014-01-10 엘지이노텍 주식회사 Motor
KR20160001681A (en) * 2014-06-27 2016-01-06 로베르트 보쉬 게엠베하 Pressure generator for a hydraulic vehicle brake system
KR20160082053A (en) * 2014-12-30 2016-07-08 엘지이노텍 주식회사 Motor
KR20170011142A (en) * 2015-07-21 2017-02-02 엘지이노텍 주식회사 Housing of motor, Motor and Stabilizer apparatus having the same
KR101917961B1 (en) * 2017-09-26 2018-11-13 (주)타마스 Electronic Brake System with Ball Screw

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102021102500A1 (en) 2021-02-03 2022-08-04 Nidec Motors & Actuators (Germany) Gmbh Electric motor with deep-drawn motor housing

Also Published As

Publication number Publication date
KR102155450B1 (en) 2020-09-11

Similar Documents

Publication Publication Date Title
WO2020251146A1 (en) Hollow shaft motor
WO2021002603A1 (en) Hollow shaft motor
WO2020096191A1 (en) Hollow shaft motor
CN102256750B (en) Electrical motor having rotor support shield
US4355785A (en) Electrically driven sheave
WO2019066257A1 (en) Electronic brake motor structure with ball screw
EP0762611B1 (en) Compound ball bearing
CN1322248C (en) Braking device structure for lifter
WO2020080657A1 (en) Hollow shaft motor
EP1018604A3 (en) Dynamic pressure bearing motor
CN106655592A (en) Moment motor structure
WO2020159078A1 (en) Motor with novel hollow shaft
CN1390163A (en) Overmolded motor bearing
EP0758155B1 (en) Electric drive motor with a compound bearing assembly
EP4101054A1 (en) Hollow shaft motor
WO2019209093A1 (en) Wheel bearing assembly
WO2023017971A1 (en) Hollow shaft motor
WO2020159231A1 (en) Vehicle wheel bearing having improved sealing function
CN112503094A (en) Axial magnetic suspension bearing, motor and air conditioner
CN101877510B (en) Motor component used for anti-lock brake system
WO2022177309A1 (en) Motor
CN216530855U (en) Integrated bearing structure and external rotor motor using same
WO2022220588A1 (en) Motor
CN216774472U (en) Direct-current brushless outer rotor motor
WO2004034550A1 (en) High axial force motor

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 20823631

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 20823631

Country of ref document: EP

Kind code of ref document: A1