CN113167011B

CN113167011B - Drying machine

Info

Publication number: CN113167011B
Application number: CN201980079267.5A
Authority: CN
Inventors: 裴祥训; 赵洪准; 金贤中
Original assignee: LG Electronics Inc
Current assignee: LG Electronics Inc
Priority date: 2018-11-30
Filing date: 2019-11-28
Publication date: 2024-06-11
Anticipated expiration: 2039-11-28
Also published as: CN118374956A; CN118374959A; CN118374952A; AU2023278044A1; CN118374957A; CN113167011A; AU2023263555A1; AU2019386525A1; CN118374953A; KR20200066169A; AU2023263559A1; AU2019386525B2; AU2023214251A1; CN118374954A; CN118374961A; US20210404107A1; CN118374951A; CN118374960A; AU2023263561A1; EP3889340A4

Abstract

The present application relates to a dryer, comprising: a housing forming an appearance; a drum disposed inside the housing and accommodating a drying object; and a driving unit configured to drive the drum, the drum including a motor including a stator and a rotor, wherein the housing includes a rear housing forming a rear appearance of the dryer, the rotor is rotatably supported on the rear housing outside the rear housing so as to be coaxial (axis) with a rotation axis (axis) of the drum, and the stator is fixed to the rear housing outside the rear housing.

Description

Drying machine

Technical Field

The present application relates to a dryer, and more particularly, to a dryer for drying an object in a drum being rotated.

Background

The dryer is a device for drying an object, and may be referred to as a device for drying an object by supplying hot air into an object accommodating portion.

There is widely used a drum dryer in which an object accommodating portion is formed in a cylindrical drum shape, and hot air is supplied into the drum while the drum is rotated. In particular, a drum dryer that rotates about a substantially horizontal axis is widely used as a home dryer.

In such a drum dryer, a motor for rotating a drum is used, and a driving force of the motor is transmitted to the drum through a power transmission part such as a belt, so that the drum rotates. Typically, the rotation axis of the motor and the rotation axis of the drum are different from each other. The drum dryer may be referred to as a belt type.

Therefore, power loss may occur by a power transmission part such as a belt, and a separate space is required inside the housing to install the motor and the power transmission part such as the belt.

In recent years, most of the drum type washing machines produced may be referred to as direct-coupled (or direct-drive) drum type washing machines, rather than the belt type. By direct connection, it is meant that the rotation shaft of the motor and the rotation shaft of the drum are formed in a coaxial form, and the stator of the motor is generally mounted on the rear wall (or lower wall) of the tub. In general, a motor used in a washing machine is referred to as a direct drive (DD: DIRECT DRIVE) motor, and such a washing machine is referred to as a DD washing machine.

The direct connection type has a great advantage over the belt type. As an example, the driving RPM of the drum and the torque of the drum may be variously changed and controlled in various environments. In addition, control of the rotation direction of the drum, control of the rotation angle of the drum, and the like can be very easily performed. In addition, the energy-saving device has the advantages of reducing power loss and saving energy.

Of course, in the case of a laundry dryer (also called a "combination"), an outer tub is provided, and thus a direct connection type can be applied. However, in the case of a simple dryer that does not provide a washing function, there is no constitution equivalent to the tub, and thus it is not easy to implement a direct connection dryer. That is, even the direct connection type having a great advantage over the belt type is not easy to apply to the dryer.

On the other hand, a dryer in which a rotor is directly connected to a rotation shaft for driving a drum is disclosed in JP1982-124674 or KR 291966. However, these prior art patents disclose a configuration in which a fan housing is provided, whereby a motor is supported by the fan housing, or the motor is supported by a separate structure. Therefore, the structure of the driving part is complicated and it is not easy to stably support the motor.

Disclosure of Invention

Problems to be solved by the invention

By the present application, it is intended to provide a direct connection dryer (DD dryer).

With an embodiment of the present application, it is intended to provide a dryer in which a motor is mounted to a rear housing for forming a rear outer shape of the dryer and supporting, so that the motor can be stably supported. That is, by mounting the motor to the rear housing, which is one of the structural frames for forming the outer shape of the dryer and supporting, the additional construction is minimized and a stable dryer is provided.

By an embodiment of the present application, it is intended to provide a direct connection dryer capable of drying using a circulation flow path of air.

With an embodiment of the present application, it is intended to provide a dryer in which a large air volume can be provided and an air volume variable area can be effectively increased by separately controlling RPM of a drum and RPM of a fan by distinguishing a fan motor for circulating air from a motor for driving the drum.

With an embodiment of the present application, it is intended to provide a dryer in which a circulation flow path of air for drying is separated from a motor, thereby preventing flow resistance from being generated by the motor, so that air flow resistance can be reduced.

By an embodiment of the present application, it is intended to provide a direct connection type dryer in which a flow path structure of inflow of dry air from the rear of a drum and discharge of air from the front of the drum can be applied.

With an embodiment of the present application, it is an object to provide a direct connection type dryer in which a motor is disposed in a space outside a housing instead of a space inside the housing for disposing a drum, so that a space inside the housing can be ensured and a degree of freedom in designing a flow path can be improved.

By an embodiment of the present application, it is intended to provide a direct connection type dryer capable of driving a motor at an optimal motor efficiency bandwidth even though there is a difference between a drum rotation bandwidth of the dryer and an optimal efficiency bandwidth of the motor.

By an embodiment of the present application, it is intended to provide a direct connection type dryer capable of improving drying performance by increasing an area of inflow of air to a drum.

By an embodiment of the present application, it is intended to provide a dryer that allows hot air to flow into the interior of a drum through a region of the drum rear wall in the shape of a circular ring (doughnut) from which a central portion and outer corners are removed, thereby enabling the hot air to flow into the interior of the drum three-dimensionally. That is, it is intended to provide a dryer capable of increasing a heat transfer area between hot air and a drying object by supplying the hot air in a cylindrical shape having a hollow center.

By an embodiment of the present application, it is intended to provide a direct connection type dryer in which an increase in the front-rear width or a decrease in the volume of a drum can be prevented by compactly forming the size of a power transmission part between the drum and a motor.

By an embodiment of the present application, it is intended to provide a direct connection type dryer in which a connector is coupled to a stator in such a manner as to overlap in a front-rear direction of the dryer on one side and coupled to a decelerator in such a manner as to overlap in the front-rear direction of the dryer on the other side, by which an increase in a front-rear length of a driving part can be minimized and the stator and the decelerator can be stably fixed to a rear case.

By an embodiment of the present application, it is intended to provide a direct connection type dryer in which a rear housing can be protected by transmitting repulsive force generated by a stator and a decelerator to a connector without being directly transmitted to the rear housing. In particular, it is intended to provide a direct connection dryer in which a connector is formed by injection molding, so that the coupling of the connector with a stator and a decelerator can be facilitated, and the connector can self-cancel repulsive force transmitted from the stator and the decelerator.

By an embodiment of the present application, it is intended to provide a direct connection dryer which is easy to manufacture. In particular, it is intended to provide a direct connection type dryer which can be easily manufactured by omitting a process for coupling a decelerator and a stator to a rear case by coupling a connector to the rear case.

By an embodiment of the present application, it is intended to provide a direct connection type dryer which directly drives a drum by a motor, thereby easily controlling an accurate position and a rotation speed of the drum, and which can reduce power loss by reducing uncertainty and abrasion caused by belt slip to achieve various drum actions and to achieve an optimal drum RPM.

By an embodiment of the present application, it is intended to provide a direct connection type dryer in which an outer diameter is increased instead of an increase in thickness in order to enhance gear strength of a decelerator, so that a reduction in capacity of a drum due to an increase in thickness of the decelerator can be prevented.

By an embodiment of the present application, it is intended to provide a dryer having a front supporter contacting with and rotatably supporting a front of a drum, excluding a rear supporter contacting with and rotatably supporting a rear of the drum, so that a power loss due to the rotation support of the drum can be reduced.

Technical proposal for solving the problems

In order to achieve the above object, according to an embodiment of the present application, there may be provided a dryer including: a housing forming an appearance; a drum disposed inside the housing for accommodating a drying object; and a driving part configured to drive the drum, including a motor having a stator and a rotor, wherein the housing includes a rear housing for forming a rear appearance of the dryer, the rotor is rotatably supported at an outer side of the rear housing to be coaxial (axis) with a rotation axis (axis) of the drum, and the stator is fixed at the rear housing at an outer side of the rear housing.

The driving part includes a power transmission part that transmits a rotational force of the rotor to the drum, and the power transmission part may be disposed between the rotor and the drum. The power transmission portion preferably transmits power in such a manner that the rotor and the drum have the same axis.

The motor is preferably an outer rotor type motor provided so that the rotor rotates radially outward of the stator. The outer rotor type motor may directly use a motor employed in an existing washing machine.

The stator preferably has a hollow portion on the inner side in the radial direction thereof and is fixed to the outer side of the rear case. By inserting at least a part of the power transmission portion into the hollow portion, an increase in the front-rear distance of the power transmission portion or the driving portion can be prevented.

A connector may be included that is disposed between the stator and the rear housing and is configured to secure the stator to the rear housing and to form a front-to-rear space between the stator and the rear housing. By the connector, the stator can be firmly fixed to the rear housing, and the rotor can be rotated without interfering with the rear housing.

A portion of the connector may be inserted into the hollow of the stator. Thus, by the form-fitting, the stator can be more firmly fixed to the connector.

The connector preferably has a hollow portion on the inner side in the radial direction thereof. A part of the power transmission part is configured to be inserted into the hollow part, so that the front-rear length of the power transmission part and the driving part can be prevented from being increased.

The power transmission part may include a decelerator that converts a high RPM low torque of the rotor into a low RPM high torque of the drum. At least a portion of the decelerator is preferably inserted into and located in the hollow portion of the connector.

The power transmission portion may include: a drum shaft connected to the rear of the drum; a rotor shaft connected to the rotor; and a speed reducer disposed between the drum shaft and the rotor shaft.

The rear housing may have a shaft through-hole formed therein, and the drum shaft may pass through the shaft through-hole.

The decelerator may include: a housing; and a converting means provided inside the case for converting the high RPM low torque of the rotor into the low RPM high torque of the drum. The conversion means may comprise a plurality of gears.

The housing of the decelerator may be provided to be fixed to the outside of the rear housing. The housing of the decelerator may be directly fixed to the rear housing.

First, the housing of the decelerator may be fixed to the connector. The connector may then be secured directly to the rear housing. The connector may be disposed around the reducer housing. In this case, the connector may be fixed to the rear housing at a position where the radius in the shaft through hole is large. Therefore, more preferably, the speed reducer housing is not directly coupled with the rear housing, and the speed reducer housing is fixed to the rear housing by the connector.

The housing of the decelerator may include: a drum shaft through hole protruding forward by a predetermined length so that the drum shaft passes through the drum shaft through hole, and a bearing rotatably supporting the drum shaft is mounted therein; and a rotor shaft through hole protruding rearward by a predetermined length so that the rotor shaft passes through the rotor shaft through hole, and a bearing rotatably supporting the rotor shaft is mounted therein.

Preferably, the drum shaft through hole is inserted into and located in a shaft through hole of the rear housing, and the rotor shaft through hole is inserted into and located in a hollow portion of the stator formed on the inner side in the radial direction thereof.

The through-hole ensures a bearing support point of the rotating shaft, and provides sufficient support. The position of the through hole may be substantially a space between the rear wall of the drum and the rear case, or an internal space of the stator. Therefore, the front-rear length of the power transmission portion or the driving portion can be prevented from increasing. That is, a compact power transmission unit or driving unit can be realized.

The decelerator may include: a first sun gear that rotates integrally with the rotor shaft; a gear ring; a plurality of first planetary gears disposed between the ring gear and the first sun gear; and a first carrier rotatably supporting a plurality of the first planetary gears.

The power of the rotor shaft may be converted to a first stage at the first mount.

The first sun gear is located in front of the rotor shaft and may be formed integrally with the rotor shaft.

The decelerator may include: a second sun gear that rotates integrally with the first carrier; a gear ring; a plurality of second planetary gears disposed between the ring gear and the second sun gear; and a second carrier rotatably supporting the plurality of second planetary gears, and integrally rotating with the drum shaft.

The power of the rotor shaft can be converted into two stages at the second bracket.

The second bracket is located behind the drum shaft and may be formed integrally with the drum shaft.

The first carrier may be integrally formed with the second sun gear.

The decelerator may include an intermediate shaft extending from the first bracket toward the rear and extending from the second sun gear toward the front, and forming a coaxial line with the drum shaft and the rotor shaft between the drum shaft and the rotor shaft.

The first carrier, the second sun gear, and the intermediate shaft may be integrally formed.

Preferably, one end of the intermediate shaft is supported by a bearing so as to be rotatable independently and coaxially with the rotor shaft inside the rotor shaft, and the other end of the intermediate shaft is supported by a bearing so as to be rotatable coaxially with the drum shaft inside the drum shaft.

The ring gear for performing the first-stage conversion and the ring gear for performing the second-stage conversion are preferably single ring gears.

The first stage conversion ratio and the second stage conversion ratio are preferably the same. Thus, a very compact reduction gear can be realized. A two-stage planetary gear reducer can be realized.

The plurality of gears includes: a single gear ring; a first sun gear integrally rotated with the rotor shaft behind the inside of the ring gear; a plurality of first planetary gears disposed between the ring gear and the first sun gear; a first carrier rotatably supporting a plurality of the first planetary gears; a second sun gear that rotates integrally with the first carrier; a plurality of second planetary gears disposed between the ring gear and the second sun gear; and a second carrier rotatably supporting a plurality of second planetary gears, preferably helical gears, which rotate integrally with the drum shaft in front of the inside of the ring gear.

Preferably, the radii of the first and second planetary gears are identical to each other, and the height (thickness) of the second planetary gear is greater than the height (thickness) of the first planetary gear.

The front-rear width of the gear for performing the secondary conversion is preferably larger than the front-rear width of the gear for performing the primary conversion.

The rear housing may have a shaft through hole through which a drum shaft connected to the drum for transmitting power of the rotor to the drum passes, and may have a mounting region for mounting the driving unit radially outward around the shaft through hole.

An air supply region for supplying air to the inside of the drum may be formed at the rear case, and the air supply region may be formed at a radially outer side of the installation region centering on the installation region.

An air suction region for sucking air from the drum may be formed at the rear case, and the air suction region may be formed at a radially outer side of the air supply region.

An inflow region of air may be formed at the rear wall of the drum except for a central portion and an outermost portion in a radius direction thereof. Therefore, the hot air can be uniformly supplied to the entire drum. In particular, since the air supply area can be increased, deviation of the flow velocity of air from the rear wall of the drum to the front can be significantly reduced. Thus, uniform drying can be achieved.

It is preferable that a flow path duct is provided to be combined with the rear housing at an outer side of the rear housing and to cover the air suction area and the air supply area to form an air flow space between the flow path duct and the rear housing. That is, a part of the section for supplying air to the inside of the drum is preferably provided outside the rear casing, that is, outside the casing, through the flow path duct.

The flow path conduit preferably includes: an inner bonding part bonded with the rear housing between a mounting area and an air supply area of the rear housing; an outer bonding part surrounding the entire air supply area and air suction area of the rear housing and bonded with the rear housing; and an expansion part which expands from between the inner and outer combining parts toward the rear of the rear housing to form an air flow space.

Therefore, the air flowing into the inside of the flow path duct from the one side lower portion of the rear casing can flow into the inside of the drum through the flow path duct in a state having a very wide area except for the center and edge portions of the drum.

In order to cover the driving part exposed to the outside of the dryer from the inside in the radial direction of the inside joint part, a driving part cover coupled to the flow path pipe from the rear of the flow path pipe may be included to cover the inside joint part.

The driving portion cover is preferably formed with a plurality of openings that allow air to flow in and out into the space for accommodating the power transmission portion. The power transmission portion may be cooled by flowing air having a relatively low temperature into the power transmission portion, and discharging air having a relatively high temperature. That is, cooling can be performed by natural convection due to a temperature difference. In particular, when the power transmission unit is provided with a rotor, forced air flow may be generated by rotation of the rotor. Such a flow of air may include air flowing in through an opening portion located at the driving part cover, and may include air discharged through another opening portion located at the driving part cover.

An electric wire drawing hole for drawing electric wires from the inside of the dryer housing to the outside may be formed at an upper portion of the rear housing, the electric wires may extend to a mounting area of the rear housing through the outside of the flow path duct and be connected to the stator.

An electric wire cover covering the electric wire at an outer side of the rear housing may be provided.

The flow path pipe may be formed with a seating portion recessed toward the front for seating the wire cover, and both ends of the wire cover may be respectively combined with the rear housing.

A wire cover coupling region for coupling one end of the wire cover may be formed between the mounting region and the air supply region of the rear case.

The rear wall of the drum is preferably formed with: a mounting area opposite to the mounting area of the rear housing; and an air intake area opposite to the air supply area of the rear housing.

A gasket disposed between the rear case and the rear wall of the drum may be included such that air supplied from the air supply area of the rear case flows into the air suction area of the drum.

The gasket may include: an inner gasket provided to prevent air from leaking between the rear case and the rear wall of the drum to a radially inner side of an air suction area of the drum; and an outer gasket provided to prevent air from leaking between the rear case and the rear wall of the drum to a radially outer side of an air suction area of the drum.

The inner gasket may include an extension portion extending obliquely toward the radially inner side and the rear wall of the drum, and the outer gasket may include an extension portion extending obliquely toward the radially outer side and the rear wall of the drum.

The gasket is preferably arranged to extend towards the drum after being fixed to the inner side of the rear housing. That is, it is preferable to mount the gasket to the fixed rear housing, not the drum that rotates.

The blower fan for making the air flow into the flow channel pipe and the heating part for heating the air flowing into the flow channel pipe are preferably provided in the inner space of the housing. The heating portion may be implemented by a heat pump. By the heat pump, the air can be heated, and moisture in the air can be condensed.

The heated air is guided by the blower fan to the inside of the flow path duct as the outside of the drying. The heated air flows into the drum from the rear of the drum through the flow path duct. The air heat-exchanged inside the drum is discharged from the front of the drum. The discharged humid air is cooled in the evaporator of the heat pump, the moisture contained therein is condensed and converted into dry air, and the dry air is heated in the condenser of the heat pump. The heated air again flows into the inside of the drum, whereby a circulation structure of the air can be formed.

In order to achieve the above object, according to an embodiment of the present application, there may be provided a dryer including: a rear housing forming a rear appearance of the dryer; a drum disposed in front of the rear housing for accommodating a drying object; a motor configured to drive the drum, the motor including a stator fixed to the rear housing from a rear outer side of the rear housing, and a rotor rotatably supported to the rear housing at the rear outer side of the rear housing and configured to rotate at a radially outer side of the stator; and a flow channel pipe which is positioned at the periphery of the motor at the rear outer side of the rear housing and is fixed to the rear housing, and is configured to guide the hot air flowing from the front of the rear housing to the inside of the drum.

In order to achieve the above object, according to an embodiment of the present application, there may be provided a dryer including: a rear housing forming a rear appearance of the dryer; a drum disposed in front of the rear housing for accommodating a drying object; a power transmission unit configured to drive the drum, the power transmission unit being rotatably fixed to the rear outer side of the rear housing; and a flow channel pipe which is positioned on the outer periphery of the driving part at the rear outer side of the rear housing and is fixed to the rear housing, and is arranged to guide the hot air flowing from the front of the rear housing to the inside of the roller.

The power transmission part is located at a position corresponding to the rotation center part of the drum, and thus, hot air can be supplied to the outer side of the rotation center part of the drum in the radial direction via the flow path duct. That is, the hot wind may be supplied to the inside of the drum in a circular ring shape. Thus, a three-dimensional large air volume can be supplied to the inside of the drum.

The rear housing and the flow path duct may be coupled to each other, thereby forming an air flow space inside. Thus, a portion of the rear housing may also form a portion of the duct. That is, the flow path duct may form an air flow space between it and the rear housing. Therefore, the duct can be easily formed by closely bonding the flow path duct of the front opening to the rear case.

The flow path conduit may include: an inner joint part which is combined with the rear shell; an outer joining portion joined to the rear housing outside the inner joining portion; and an expansion part which expands from between the inner and outer combining parts toward the rear of the rear housing to form an air flow space.

The space for disposing the motor and the air flow space are preferably partitioned by the flow path duct at the rear of the rear housing. In other words, the space for disposing the motor may be divided by the space inside the flow path duct, and the rear housing. Therefore, the flow resistance of the air caused by the motor is not generated.

The inner joining portion may be joined to the rear case from a radially outer side of the stator or the rotor.

Thus, the flow path pipe may have a circular ring shape surrounding the installation space of the motor. Of course, a part of the annular shape may be deformed.

In order to cover the drive unit exposed to the outside of the dryer from the inside in the radial direction of the inside joint, it is preferable that the drive unit cover is coupled to the flow path duct at the rear of the flow path duct. That is, the center portion of the annular shape is preferably covered by the driving portion cover. Therefore, the rotor in rotation and the stator connected to the electric wire can be prevented from being exposed to the outside of the dryer.

The rear case is preferably formed with: an air supply area for supplying air to the inside of the drum; and an air suction area for sucking air from the inside of the drum. That is, the air passes through the region from the front to the rear of the rear case or from the rear to the front. Herein, the front of the rear housing may be referred to as an inner space of the dryer surrounded by the housing.

The air suction region may be formed at a radially outer side of the air supply region. When the air supply area is substantially the upper, lower, left, right, central portion of the rear housing, the air intake area may be formed at the left lower portion of the rear housing.

That is, the air discharged from the inside of the dryer through the left lower portion of the rear housing may flow toward the upper right along the inside of the flow path duct and then be supplied to the inside of the drum.

The flow path duct may be provided to cover both the air suction area and the air supply area. Thus, the circular ring-shaped flow path duct may have a shape of which a portion extends to the left lower portion of the rear housing.

A blower fan for generating air flow and a heating part for heating air may be included, and the blower fan and the heating part may be located in front of the rear housing, i.e., inside the housing. Therefore, a structure for heating and flow generation of air is not provided behind the rear case. Thereby, an increase in the degree of freedom of design of the flow path and a simple structure can be achieved.

The air may flow into the inside of the flow path duct from the front to the rear of the air suction area of the rear case, and the air may flow into the inside of the drum from the rear to the front of the air supply area of the rear case.

A shaft through hole is formed in the rear case, a drum shaft connected to the drum to transmit power of the rotor to the drum penetrates the shaft through hole, and an attachment region for attaching the motor is preferably formed radially outward around the shaft through hole.

Preferably, the flow path duct is coupled to the rear housing at a radially outer side of the installation region, and an air flow space inside the flow path duct is separated from the installation region and the motor.

An air supply region covered by the flow path duct for supplying air to the inside of the drum may be formed at the rear housing, and an air suction region opposite to the air supply region of the rear housing may be formed at the rear wall of the drum.

The air supply area of the rear housing may have a circular ring shape, and the air suction area of the drum opposite thereto may also have a circular ring shape.

The circular ring-shaped air suction area may supply stereoscopic hot air inside the drum. That is, hot air having a hollow cylindrical shape in the center can be supplied into the drum. The air suction area is preferably not formed at the outer corner of the rear wall of the drum. By such cylindrical three-dimensional hot air, the heat exchange area with the drying object in the drum can be effectively increased.

Preferably, a gasket is provided between the rear case and the rear wall of the drum such that air supplied from the air supply area of the rear case flows into the air suction area of the drum.

Therefore, it is possible to prevent the hot air from leaking to the outside from between the drum and the rear case, and also to prevent the hot air from flowing into the decelerator or the motor.

Preferably, the inner gasket includes an extension portion extending obliquely toward the radially inner side and the rear wall of the drum, and the outer gasket includes an extension portion extending obliquely toward the radially outer side and the rear wall of the drum.

By means of such an extension, the sealing efficiency can be improved and friction and damage of the gasket can be minimized.

Preferably, a wire drawing hole for drawing out a wire from the front to the rear is formed in an upper portion of the rear case, the wire extending to a mounting area of the rear case via an outside of the flow path pipe and being connected to the motor.

After the motor and the flow path duct are mounted to the rear housing, the wire connection can be easily performed, and the wires can be protected by the wire cover. Further, after the wire cover is mounted, the driving part cover may be finally coupled to the flow path duct or the rear case.

In order to achieve the above object, according to an embodiment of the present application, there may be provided a dryer including: a housing forming an external appearance of the dryer; a drum disposed inside the housing for accommodating a drying object; a driving part configured to drive the drum, including a motor having a stator and a rotor; and a flow path duct for allowing air sucked from the inside of the drum to flow into the inside of the drum, wherein the casing includes a rear casing forming a rear appearance of the dryer, having a power transmission part installation area for transmitting a driving force to the drum, an air suction area, and an air supply area, the power transmission part being installed to the installation area from the rear of the rear casing, the flow path duct covering the air suction area and the air supply area except the installation area and being combined with the rear casing, and an air flow space is formed between the flow path duct and the rear casing.

In order to achieve the above object, according to an embodiment of the present application, there may be provided a dryer having: a housing forming an appearance; a drum disposed inside the housing for accommodating a drying object; and a driving part configured to drive the drum, including a motor having a stator and a rotor, wherein the housing includes a rear housing forming a rear appearance of the dryer, the rotor is rotatably supported at an outer side of the rear housing to be coaxial (axis) with a rotation axis (axis) of the drum, and the stator is fixed to the rear housing at an outer side of the rear housing.

In order to achieve the above object, according to an embodiment of the present application, there may be provided a dryer including: a rear housing forming a rear appearance of the dryer; a drum disposed in front of the rear housing for accommodating a drying object; a motor configured to drive the drum, the motor including a stator fixed to the rear case at a rear outer side of the rear case, and a rotor rotatably supported by the rear case at a rear outer side of the rear case and configured to rotate at a radially outer side of the stator; a rotor shaft integrally rotated with the rotor, extending from a rear wall of the drum to a rear of the rear housing through the rear housing; a drum shaft integrally rotated with the drum; and a speed reducer including an intermediate shaft that performs power conversion between the rotor shaft and the drum shaft, connecting the rotor shaft and the drum shaft to be coaxial.

The intermediate shaft may be inserted into the hollow of the drum shaft and the hollow of the rotor shaft such that the three shafts form a coaxial shaft. The manufacturing process is very easy since the three shafts are simply connected by insertion.

The drum shaft, the reducer and the rotor shaft may be manufactured and treated as one assembly. The coupling of the drum shaft and the drum may be performed at the inner side of the drum, and the coupling of the rotor shaft and the rotor may be performed at the rear outer side of the rotor. Therefore, the combination of the drum, the drum shaft, the decelerator, the rotor shaft, and the rotor can be performed very easily.

The rotor shaft, the drum shaft, and the intermediate shaft may be separately formed, and may be sequentially connected for power transmission. Such a connection location is preferably located inside the housing of the retarder. Therefore, the disconnection between the shafts can be prevented by the housing of the reduction gear.

The rotor shaft and the intermediate shaft may be connected to rotate independently of each other through bearings, and the drum shaft and the intermediate shaft may also be connected to rotate independently of each other through bearings.

The stator may have a hollow portion on an inner side in a radial direction thereof, and be fixed to a rear outer side of the rear case.

Preferably, a connector is provided between the stator and the rear housing, arranged to fix the stator to the rear housing, and a front-rear space is formed between the stator and the rear housing.

A portion of the connector may be inserted into the hollow of the stator. That is, the stator and the connector may be coupled to each other in such a manner as to overlap in the front-rear direction of the dryer. This minimizes an increase in the front-rear length of the driving section. In addition, the bonding strength can be further increased by the form-bonding of the two.

The connector may have a hollow portion on the inner side in the radial direction thereof.

The decelerator includes the housing and the intermediate shaft, and may include a conversion device provided inside the housing for converting a high RPM low torque of the rotor into a low RPM high torque of the drum.

At least a portion of the decelerator may be inserted into and located in the hollow portion of the connector. That is, at least a portion of the reducer case may be inserted into the hollow portion of the connector. Therefore, the decelerator and the connector can be coupled to each other in such a manner as to overlap in the front-rear direction of the dryer. This minimizes an increase in the front-rear length of the driving section. In addition, the bonding strength can be further increased by the form-bonding of the two.

The housing of the decelerator may be provided to be fixed to the outside of the rear housing.

The connector may be fixedly coupled to the rear of the rear housing. The reducer housing and the stator may be fixedly coupled to the connector. Thus, the reducer housing and stator may be indirectly secured to the rear housing through the connector. That is, first, the decelerator housing and the stator may be fixedly coupled to the connector, and then, the connector may be fixedly coupled to the rear housing. Accordingly, a process and a coupling structure (e.g., a stud, a bolt, or a screw) for fixedly coupling the speed reducer housing and the stator to the rear housing can be omitted.

Therefore, the repulsive force generated by the decelerator and the stator can be transmitted to the connector without being directly transmitted to the rear housing. This can protect the rear case.

The connector may be formed by injection molding. Can be manufactured from plastics, in particular engineering plastics. The repulsive force can be offset by itself in terms of the characteristics of the material. Further, since the shape molding becomes easy, the molded structure can be formed with the stator and the decelerator very accurately.

The conversion device may include: a first sun gear that rotates integrally with the rotor shaft; a gear ring; a plurality of first planetary gears disposed between the ring gear and the first sun gear; and a first carrier rotatably supporting the plurality of first planetary gears, wherein the power of the rotor shaft is converted into a first stage.

Preferably, the first sun gear is located in front of the rotor shaft and is integrally formed with the rotor shaft.

The conversion device may include: a second sun gear that rotates integrally with the first carrier; a gear ring; a plurality of second planetary gears disposed between the ring gear and the second sun gear; and a second carrier rotatably supporting the plurality of second planetary gears, the second carrier being rotatable integrally with the drum shaft, the power of the rotor shaft being convertible to a second stage.

Preferably, the second bracket is located behind the drum shaft and is integrally formed with the drum shaft.

The first carrier is preferably integrally formed with the second sun gear.

The intermediate shaft may be formed to extend rearward from the first carrier and forward from the second sun gear.

The first carrier, the second sun gear and the intermediate shaft are preferably integrally formed.

One end of the intermediate shaft may be supported by a bearing so as to be rotatable independently of the rotor shaft coaxially with the rotor shaft inside the rotor shaft, and the other end of the intermediate shaft may be supported by a bearing so as to be rotatable independently of the drum shaft coaxially with the drum shaft inside the drum shaft.

The speed reducer is a two-stage planetary gear speed reducer, and the first-stage conversion ratio and the second-stage conversion ratio may be set to be the same.

The decelerator may include: a single gear ring; a first sun gear integrally rotated with the rotor shaft behind the inside of the ring gear; a plurality of first planetary gears disposed between the ring gear and the first sun gear; a first carrier rotatably supporting a plurality of the first planetary gears; a second sun gear that rotates integrally with the first carrier; a plurality of second planetary gears disposed between the ring gear and the second sun gear; and a second carrier rotatably supporting the plurality of second planetary gears, and integrally rotating with the drum shaft in front of the inside of the ring gear.

In order to achieve the above object, according to an embodiment of the present application, there may be provided a dryer including: a rear housing forming a rear appearance of the dryer and supporting; a drum disposed in front of the rear housing for accommodating a drying object; a motor configured to drive the drum, including a stator having a hollow portion and a rotor configured to rotate radially outward of the stator; a connector having one side inserted into the hollow portion of the stator and coupled to the stator and the other side coupled to the rear housing from the rear of the rear housing and having a hollow portion; and a decelerator inserted into the hollow of the connector and coupled with the connector, configured to convert power of the rotor and transmit to the drum.

The driving part may include a power transmission part transmitting a rotational force of the rotor to the drum, and the power transmission part may be disposed between the rotor and the drum. The power transmission part preferably transmits power in such a manner that the rotor and the drum have the same axis.

The housing of the decelerator may be provided to be fixed to the outside of the rear housing. The reducer housing may be directly secured to the rear housing.

The housing of the decelerator may include: a drum shaft through hole protruding forward by a predetermined length so that the drum shaft penetrates the drum through hole, and a bearing rotatably supporting the drum shaft is mounted therein; and a rotor shaft through hole protruding rearward by a predetermined length so that the rotor shaft passes through the rotor shaft through hole, and a bearing rotatably supporting the rotor shaft is mounted therein.

The first sun gear is located in front of the rotor shaft and may be integrally formed with the rotor shaft.

The second bracket is located at a rear of the drum shaft, and may be integrally formed with the drum shaft.

The first carrier may be integrally formed with the second sun gear.

Preferably, one end of the intermediate shaft is supported by a bearing so as to be rotatable independently of the rotor shaft coaxially with the rotor shaft, and the other end of the intermediate shaft is supported by a bearing so as to be rotatable independently of the drum shaft coaxially with the drum shaft inside the drum shaft.

Effects of the invention

The application can provide a direct-connected dryer. In particular, it is possible to provide a direct connection type dryer capable of using a direct connection type motor employed in the existing washing machine.

By an embodiment of the present application, it is possible to provide a dryer in which a motor is mounted to a rear housing for forming a rear outer shape of the dryer and supporting, so that the motor can be stably supported.

In the present application, it is possible to minimize additional constitution and provide a stable dryer by mounting a motor to a rear housing which is one of structural frames for forming an outer shape of the dryer and supporting.

According to an embodiment of the present application, a direct connection dryer capable of drying using a circulation flow path of air can be provided.

By an embodiment of the present application, it is possible to provide a dryer in which a larger air volume can be provided and an air volume variable region can be effectively increased by separately controlling RPM of a drum and RPM of a fan by distinguishing a fan motor for circulating air from a motor for driving the drum.

By an embodiment of the present application, it is possible to provide a dryer in which a circulation flow path of air for drying is separated from a motor, thereby preventing flow resistance from being generated by the motor, and thus enabling air flow resistance to be reduced.

By an embodiment of the present application, it is possible to provide a direct connection type dryer in which a flow path structure of flowing dry air from the rear of a drum and discharging air from the front of the drum can be applied.

By an embodiment of the present application, it is possible to provide a direct connection type dryer in which a motor is disposed in a space outside a housing instead of a space inside the housing for disposing a drum, so that a space inside the housing can be ensured and a degree of freedom in designing a flow path can be improved.

By an embodiment of the present application, it is possible to provide a direct connection type dryer capable of driving a motor at an optimal motor efficiency bandwidth even though there is a difference between a drum rotation bandwidth of the dryer and an optimal efficiency bandwidth of the motor.

By an embodiment of the present application, it is possible to provide a direct connection type dryer capable of improving drying performance by increasing an area of inflow of air to a drum.

An object of an embodiment of the present application is to provide a dryer that allows hot air to flow into the drum through a circular ring-shaped area of the rear wall of the drum from which the central portion and the outer corners are removed, thereby allowing the hot air to flow into the drum three-dimensionally. That is, it is possible to provide a dryer capable of increasing the heat transfer area between the hot air and the drying object by supplying the hot air having a hollow cylindrical shape at the center.

By an embodiment of the present application, it is possible to provide a direct connection type dryer in which an increase in the front-rear width or a decrease in the volume of a drum can be prevented by compactly forming the size of a power transmission part between the drum and a motor.

By an embodiment of the present application, it is possible to provide a direct connection type dryer in which a connector is coupled to a stator in such a manner as to overlap in a front-rear direction of the dryer on one side and coupled to a decelerator in such a manner as to overlap in the front-rear direction of the dryer on the other side, by which an increase in a front-rear length of a driving part can be minimized and the stator and the decelerator can be stably fixed to a rear case.

By an embodiment of the present application, it is intended to provide a direct connection type dryer in which a rear housing can be protected by transmitting repulsive force generated by a stator and a decelerator to a connector without being directly transmitted to the rear housing. In particular, it is possible to provide a direct connection type dryer in which a connector is formed by injection molding, so that the coupling of the connector with the stator and the decelerator can be facilitated, and the connector can self-cancel repulsive force transmitted from the stator and the decelerator.

By an embodiment of the present application, it is intended to provide a direct connection dryer which is easy to manufacture. In particular, it is possible to provide a direct connection type dryer which can be easily manufactured by omitting a process for coupling a decelerator and a stator to a rear case by coupling a connector to the rear case.

By an embodiment of the present application, it is possible to provide a direct connection type dryer which directly drives a drum by a motor, thereby easily controlling an accurate position and a rotation speed of the drum, and which can reduce power loss by reducing uncertainty and abrasion caused by belt slip to achieve various drum actions and to achieve an optimal drum RPM.

By an embodiment of the present application, it is possible to provide a direct connection type dryer in which an outer diameter is increased instead of a thickness is increased in order to reinforce a gear lightness of a decelerator, so that a reduction in capacity of a drum due to an increase in thickness of the decelerator can be prevented.

By an embodiment of the present application, it is possible to provide a dryer having a front supporter in contact with and rotatably supporting a front of a drum, excluding a rear supporter in contact with and rotatably supporting a rear of the drum, so that power loss due to the rotational support of the drum can be reduced.

Drawings

Fig. 1 shows a cross section of a dryer according to an embodiment of the present application.

Fig. 2 illustrates a rear state of a dryer according to an embodiment of the present application.

Fig. 3 shows a portion of a driving part of a dryer in an enlarged manner according to an embodiment of the present application.

Fig. 4 illustrates a state in which the drum, the rear housing, and the driving part of the dryer according to an embodiment of the present application are disassembled.

Fig. 5 illustrates a front state of a drum according to an embodiment of the present application.

Fig. 6 illustrates a rear state of the drum according to an embodiment of the present application.

Fig. 7 illustrates an air inflow structure in a driving part of a dryer according to an embodiment of the present application.

Fig. 8 illustrates a state in which a rear housing portion is viewed from the outside of the dryer according to an embodiment of the present application.

Fig. 9 shows a state in which the rear housing portion is viewed from the inside of the dryer according to an embodiment of the present application.

Fig. 10 shows a graph showing the necessity of a decelerator and a deceleration ratio in a dryer according to an embodiment of the present application.

Fig. 11 shows a state in which a decelerator constitution of a dryer according to an embodiment of the present application is disassembled.

Fig. 12 shows a combined state of the constitution for the one-stage conversion of the speed reducer.

Fig. 13 shows a combined state of the constitution for the two-stage conversion of the speed reducer.

Fig. 14 is a graph comparing a standard deviation of speeds of drum cross-sectional positions in a dryer and a conventional dryer according to an embodiment of the present application.

Detailed Description

Hereinafter, a dryer according to an embodiment of the present application will be described in detail with reference to the accompanying drawings.

First, the main configuration of the dryer will be described with reference to fig. 1 and 2. In this specification, for convenience of explanation, the direction of the door 140 of the dryer shown in fig. 1 is referred to as a front direction, and the direction of the driving part 200 is referred to as a rear direction.

The dryer 10 includes: a housing (case) 100, 120, 130, 150 for forming an outline; and a drum 20 disposed inside the housing. A drying object may be provided inside the drum 20. In the case of a laundry dryer, laundry may be put into the inside of the drum 20 and dried.

The housing may include: an upper housing 100 for forming a top surface of the dryer 10; a front housing 120 for forming a front face; a rear case 130 for forming a rear surface; and a side case 150 for forming a side. Further, the housing may include: a dryer base 155 for forming the bottom of dryer 10. The cabinet is formed with an inner space in which the drum 20 is included for accommodating various constitutions.

Further, the upper case 100, the front case 120, the rear case 130, the side case 150, and the base 155 are structurally coupled to each other. Thus, each of the housing and the base forms not only an external appearance of the dryer 10 in any one direction, but also a support structure for supporting an external appearance of the dryer.

A door 140 may be provided at the front case 120, and laundry may be put into the drum 20 by opening the door 140.

The drum 20 may be provided to be rotatable with respect to a horizontal axis parallel to the ground.

The drum 20 is formed in a cylindrical shape, and the front of the drum 10 is opened to allow laundry to be put in.

A plurality of lifting ribs (lifter) 30 may be provided on the inner wall of the drum 20. The lifting rib 30 may be provided to extend in the front-rear direction. The lifting rib 30 may be provided to rotate integrally with the drum 20. As the drum 20 rotates, the lifting ribs 30 lift the laundry, and if the drum 20 rotates further, the laundry leaves the lifting ribs 30 and falls under the force of gravity. As the drum 20 rotates, the shaking of the laundry inside the drum 20 can be smoother and more active by means of the lifting ribs 30. Accordingly, the laundry may be uniformly exposed to the hot wind.

In the present embodiment, a driving part 200 for driving the drum 20 is located at the rear of the drum 20. The driving unit 200 includes a motor 260, and the motor 260 includes a rotor 270 and a stator 280. The rotation axis (axis) of the rotor 270 and the rotation axis (axis) of the drum 20 may be formed to be coaxial. That is, the drum 20 and the rotor 270 are rotated in a state having the same rotation center. Therefore, the dryer of the present embodiment may be referred to as a direct connection dryer.

In order to transmit the power of the rotor 270 to the drum 20, a drum shaft (drum shaft) 210 is provided at the drum 20. The drum shaft 210 is connected to the center of the rear wall 22 of the drum 20. Accordingly, as the drum shaft 210 rotates, the drum 20 rotates integrally with the drum shaft 210.

For supporting the front of the drum 20, a front supporter (supporter) 160 may be provided. The front support 160 may be coupled to the rear of the front housing 120, or may be formed as a part of the front housing 120.

In a conventional belt type dryer, an opening is formed not only in front of a drum but also in rear of the drum, and substantially, only a cylindrical side wall having an opening in front and rear is formed in the drum. Further, a rear supporter is provided at a rear opening of the drum. That is, the rear supporter supports the drum in a state where the rear opening is blocked. Since the rear support is fixed, only the side wall of the drum rotates by the belt.

However, in the present embodiment, the drum 20 includes not only the cylindrical side wall 21 but also the rear wall 22, and the side wall 21 rotates integrally with the rear wall 22. Therefore, the drum rear supporting structure in this embodiment is different from the existing belt dryer.

Unlike the drum of the conventional dryer, in the drum of the present embodiment, the side wall 21 of the drum 20 rotates integrally with the rear wall 22. The drum in this embodiment may be similar to that of a washing machine. However, since it is not a drum for performing washing, the sidewall of the drum in the present embodiment is not formed with a through hole for air or water to enter and exit. However, a plurality of through holes or through portions are formed in the rear wall 22 to allow communication of air and to exclude the entry and exit of laundry. This will be described later.

The rear of the drum 20 may be rotatably supported by the drum shaft 210. More specifically, since the drum shaft 210 is rotatably supported by the rear housing 130, the rear of the drum is rotatably supported with respect to the rear housing 130. The rear housing 130 is a structure for forming a supporting structure of the entire dryer. Accordingly, the rear of the drum 20 may be rotatably and firmly supported by the rear housing 130 as a supporting structure of the dryer.

As shown in fig. 3, the drum shaft 210 extends rearward from the center of the rear wall 22 of the drum 20. Further, a driving part 200 and power transmission parts 210, 220, 230 are provided at the rear of the drum rear wall 22. The power transmission parts 210, 220, 230 include the drum shaft 210, and the driving part 200 includes the motor 260 and the power transmission parts 210, 220, 230.

The power transmission parts 210, 220, 230 are disposed between the drum 20 and a rotor 270 of a motor 260, thereby transmitting the driving force of the rotor to the drum 20. Accordingly, the driving part 200 including the power transmission parts 210, 220, 230 may be located at the rear of the drum 20.

The motor 260 may include: a stator 280; and a rotor 270 rotatably provided on the outer side of the stator 280 in the radial direction. Accordingly, the motor 260 may be referred to as an outer rotor type motor. Such an outer rotor type motor is widely used in direct connection type washing machines. However, in the conventional dryer, as described above, it is difficult to realize the direct connection type dryer, and thus it is not easy to use the outer rotor type motor.

In the present embodiment, the stator 280 is preferably disposed outside the rear housing 130. In particular, it is preferable to be provided to be fixed to the outside of the rear case 130. The rear housing 130 is a structure that forms an outer shape of the dryer 10 and an inner space of the dryer 10 at the rear of the dryer 10. Therefore, the rear housing 130 is fixed. Accordingly, by fixing the stator 280 to the outside of the rear case 130, the stator 280 can be firmly fixed.

Since the motor 260 is disposed at the outside of the rear housing 130, the interval between the inside of the rear housing 130 and the drum rear wall 22 may be only provided to avoid interference with the rotation of the drum 20. In addition, since the motor 260 is disposed at the outside of the rear housing 130, it is very easy to manufacture.

The stator 280 may be disposed to be spaced apart from the rear surface of the rear housing 130. That is, it is preferable that the stator 280 is coupled not to contact the rear housing 130. A connector 250 is provided between the rear housing 130 and the stator 280. The stator 280 may be said to be coupled to the rear housing 130 by the connector 250.

The decelerator 230 may be provided in the connector 250, specifically, in a hollow portion 250a of the connector 250 located at the inner side in the radial direction. That is, the decelerator 230 may be inserted into the inside of the connector 250. Therefore, the increase in the front-rear interval between the driving section 200 or the power transmission sections 210, 220, 230 can be minimized by the speed reducer 230.

The decelerator 230 may be located between the rotor 270 and the drum 20. The decelerator 230 may be configured to convert the driving force of the rotor 270 and transmit to the drum 20. Specifically, the decelerator 230 may be configured to convert the high RPM low torque of the rotor 270 into the low RPM high torque of the drum 20.

A drum shaft 210 coupled to the drum 20 is provided in front of the decelerator 230, and a rotor shaft 220 coupled to the rotor 270 is provided behind the decelerator 230. The rotor shaft 220 rotates integrally with the rotor 270, and the drum shaft 210 rotates integrally with the drum 20. Accordingly, the decelerator 230 may constitute a power transmission part converting the power of the rotor shaft and transmitting to the drum shaft 210. To ensure the efficiency and ease of such power transmission, the drum shaft 210 and the rotor shaft 220 are preferably formed coaxially.

The decelerator 230 may be installed at the rear housing 130. The decelerator 230 may be installed to directly contact the rear surface of the rear housing 130. Further, a connector 250 may be provided at the outer side of the decelerator 230 in the radial direction, and the stator 280 may be mounted to the rear housing 130 through the connector 250.

The rotor 270 rotates on the outer side in the radial direction of the stator 280, and the rotor 270 is formed to extend further forward than the stator 280 toward the rear housing 130 on the outer side in the radial direction of the stator 280. Therefore, it can be said that the front-rear separation distance between the rear housing 130 and the stator 280 is ensured by the connector 250 in order to ensure the rotation space of the rotor 270.

Further, the decelerator 230 is provided in the form of being inserted into the connector 250. Therefore, the front-rear width of the driving part 200 formed by the decelerator 230 and the motor 260 can be formed very compact. Thereby, the width expansion toward the outside of the rear housing 130 can be minimized.

Further, the driving part 200 including the power transmission parts 210, 220, 230 may be supported on a rear housing for forming an outer shape of the rear of the dryer and forming a supporting structure of the dryer.

In the present embodiment, the motor 260 and the decelerator 230 are located at the rear of the rear housing 130, and thus, there is a concern that these components may be exposed to the outside. Therefore, these structures need to be protected. For this, as shown in fig. 4, a driving part cover 180 for covering the driving part 200 may be provided at the rear of the dryer 10.

Among the structures constituting the driving unit 200, the structure formed to be maximum in the radial direction may be referred to as a rotor 270. Therefore, the structure of the driving unit 200 other than the rotor 270 may be located radially inward of the rotor 270. Therefore, the driving unit cover 180 may be formed so as to cover the rotor 270 entirely. That is, the driving part cover 180 may be formed in a disc shape having an outer diameter slightly larger than that of the rotor 270.

The driving part cover 180 may be coupled with the rear housing 130 at the rear of the rear housing 130. In contrast, the driving unit cover 180 may be coupled to a channel pipe (duct) 170 described later. The driving part cover 180 and the flow path pipe 170 described later are located only at the rear of the rear housing 130, not forming a supporting structure of the dryer. Therefore, even if the driving part cover 180 and the flow path duct 170 are removed, the support structure of the dryer is not changed. However, in the present embodiment, the drive unit cover 180 and the flow path duct 170 can be said to be provided by expanding a part of the drive unit 200 and the air flow path to the rear outside of the rear housing 130 instead of the inside of the housing 10.

In the present embodiment, there may be a rear air inflow structure that may supply air to the drum 20 from the outside of the rear housing 130. Specifically, the flow path duct 170 is mounted to the rear housing 130, whereby air is supplied to the inside of the drum 20 via the flow path duct 170.

The flow path pipe 170 may be installed at the rear surface of the rear housing 130, and a space 171 for flowing air may be formed therein. The flow channel 170 may be formed radially outward of the driving unit 200. That is, the flow path pipe 170 may be formed to surround the driving part 200.

Accordingly, the air flow space 171 inside the flow path duct 170, the motor 260, and the decelerator 230 may be structurally distinguished or separated outside the rear housing 130. Accordingly, the air flow can be smoothly performed, and the inflow of the hot air or the humid air to the motor 260 and the decelerator 230 can be prevented.

The air communication structure between the duct 170, the rear housing 130, and the drum 20 will be described later.

The motor 260 is located on the rear outside of the rear housing 130. Further, the motor 260 is surrounded by the flow path pipe 170 on the rear outside of the rear housing 130. Accordingly, the electric wire or the signal wire extends inside the housing 100, and is not easily connected to the motor 260.

In the present embodiment, the electric wire or the signal wire penetrating the rear case 130 may extend from the radially outer side to the radially inner side of the flow channel pipe 170 and be connected to the motor 260. At this time, the electric wire or the signal wire may be exposed to the outside. To prevent such exposure, a wire cover 190 may be provided.

Hereinafter, the connection and positional relationship among the drum rear wall 22, the rear housing 130, and the driving part 200 will be described in detail with reference to fig. 3 and 4. Fig. 3 is an enlarged cross-sectional view of a rear portion of the dryer shown in fig. 1, and fig. 4 is an exploded perspective view of the drum, the rear housing, and the driving part.

The rear housing 130 is located behind the drum rear wall 22. The drum rear wall 22 is constructed to rotate so that it is located at a position spaced apart from the rear housing 130.

A motor 260 is provided outside the rear housing 130. The stator 280 of the motor 260 is located at a position spaced rearward from the rear surface of the rear housing 130 by the connector 250 and is fixed to the rear housing 130.

In order to transmit the driving force of the rotor 270 of the motor to the drum 20, power transmission parts 210, 220, 230 are provided. The power transmission parts 210, 220, 230 include a drum shaft 210, a decelerator 230, and a rotor shaft 220.

In order to transmit the driving force of the rotor 270, the rotor 270 is coupled with the rotor shaft 220. The rotor shaft 220 is coaxial with the rotation shaft of the rotor 270, and integrally rotates with the rotor 270. Therefore, in order to ensure firm fastening and reliability of power transmission, a coupling (coupler) 296 may be provided. The coupling 296 may be referred to as a rotor coupling 296.

The rotor coupling 296 may be coupled to the inner side of the rotor 270 by a plurality of bolts. In addition, rotor shaft 220 may extend through rotor coupling 296 and be coupled to rotor 270 by studs (stud) 294. A spacer 295 may be interposed between the stud 294 and the rotor 270 so that the coupling based on the stud 294 becomes firm.

An internal thread may be formed at the center of the rotor shaft 220 so that the stud 294 can be fastened to the rotor shaft 220.

Additionally, the rotor shaft 220 may be serration coupled with the rotor coupling 296. The outer peripheral surface of the rotor shaft 220 may be provided with serrations, and the rotor coupling through which the rotor shaft passes may be provided with serrations. Accordingly, the driving force of the rotor can be firmly transmitted to the rotor shaft 220.

The driving force of the rotor shaft 220 is converted by the decelerator 230 and transmitted to the drum shaft 210. The drum shaft 210 may have the same or similar fastening structure as the rotor shaft 220 and is combined with the drum rear wall 22.

That is, a stud (stud) 291, a washer 292, and a roller coupling 293 may be provided. These may be the same or similar in shape and configuration as studs 294, shims 295, and rotor coupling 296 used to secure rotor shaft 220.

The stud 291 penetrates the stud through hole 29a from the inside to the outside (from the front to the rear) of the drum, and is coupled to the drum shaft 210. Further, the stud 294 penetrates through the stud through-hole from the outside to the inside (from the rear to the front) of the rotor, and is coupled to the rotor shaft 220.

The rotor shaft 220 rotates integrally with the rotor 270, and the drum shaft 210 rotates integrally with the drum 20. Accordingly, the decelerator 230 may be referred to as a device performing power conversion between the rotor shaft 220 and the drum shaft 210.

The decelerator 230 includes: a housing (housing) 231; and a switching device 240 provided inside the housing 231. The conversion device 240 may include various gears. The rotor shaft 220 and the drum shaft 210 may extend to the inside of the housing 231 and be connected to the conversion device 240. The rotor shaft 220 and the drum shaft 210 may be part of the decelerator 230 or part of the conversion device 240.

A drum shaft through hole 232 for passing the drum shaft 210 is formed in front of the housing 231. The drum shaft through hole 232 may be formed to extend forward. That is, the predetermined straight-ahead distance may be set. The drum shaft through hole 232 may be formed through the shaft through hole 130a of the rear housing 130.

The shaft through-hole 130a is formed so that the drum shaft 210 penetrates the rear case 130 from the rear wall 22 of the drum 20 and extends to the decelerator 230. Here, the drum shaft 210 is not preferably rotatably supported through the shaft through-hole 130a. This is because the rear housing 130 is formed of a plate having a relatively thin thickness, such as a steel plate, and thus it is not easy and preferable to form a bearing support structure in the through-hole formed in the plate.

Therefore, the diameter of the shaft through-hole 130a is preferably formed so that not only the drum shaft 210 but also the drum shaft through-hole 232 of the housing 231 of the reduction gear can be inserted.

The housing 231 of the decelerator may be fixedly coupled to the rear housing 130 at the rear of the rear housing 130. The drum shaft through hole 232 of the speed reducer housing 231 may extend further forward through the shaft through hole 130 a.

A bearing 234 may be provided in the drum shaft through hole 232. The drum shaft 210 may be inserted into the bearing 234. Accordingly, the drum shaft 210 may be rotatably supported by the housing 231 through the bearing 234. Since the housing 231 is fixed to the rear housing 130, the drum shaft 210 is rotatably provided to the rear housing 130 through the housing 231.

In addition, the housing 231 of the decelerator 230 may be fixedly coupled to the connector 250. The housing 231 of the decelerator may be coupled to the inside of the connector 250 in a form-fitting manner. The connector 250 may surround the housing 231 of the decelerator and be fixed to the rear housing 130 from the rear of the rear housing 130.

Accordingly, the decelerator 230 may be firmly fixed to the rear housing 130 through the connector 250. This is because the radius of the portion of the connector 250 that is coupled with the rear housing 130 (e.g., the coupling portion using bolts or studs) is larger than the radius of the housing 231 of the reduction gear.

As described above, the motor 260 may be an outer rotor type motor. Therefore, the rotor 260 rotates radially outward of the stator 280. With this structure, the hollow portion 280a can be formed inside the stator 280 in the radial direction.

A portion of the connector 250 may be inserted into the hollow 280a. Thereby, an increase in the front-rear length of the driving part 200 can be prevented, and the stator 280 can be firmly coupled to the connector 250.

The speed reducer 230 can increase the front-rear length for connecting the rotary shaft (which is a rotary shaft including a drum shaft, an intermediate shaft described later, and a rotor shaft) between the rotor 270 and the drum 20. Therefore, it is important to ensure a rotatable support point of the rotation shaft. However, in order to secure the above-described supporting point, it is not preferable to increase the entire length of the rotation shaft.

A rear portion of the housing 231 of the decelerator is preferably inserted into the hollow portion 280a of the stator 280.

A rotor shaft through hole 233 for passing the rotor shaft 220 is formed at the rear of the housing 231 of the reduction gear. The rotor shaft through hole 233 may be formed to extend rearward. That is, the predetermined rearward linear distance may be set. The rotor shaft through hole 233 is preferably inserted into the hollow portion 280a of the stator 280.

A bearing 236 may be provided in the rotor shaft through hole 233. The rotor shaft 220 may be inserted into the bearing 236. Accordingly, the rotor shaft 220 may be rotatably supported to the housing 231 through the bearing 236. The housing 231 may be fixed to the rear housing 130, in particular by means of a connector, so that the rotor shaft 220 may be said to be rotatably arranged also to the rear housing 130.

As described above, the bearing support point of the drum shaft 210 is substantially located in the space between the drum rear wall 22 and the front surface of the rear housing 130. The bearing support point of the rotor shaft 220 is substantially located inside the stator 280, that is, the hollow 280a. Therefore, the bearing support point of the entire rotation shaft can be ensured smoothly, and thus the length of the entire rotation shaft can be prevented from increasing.

In addition, since the bearings 234, 236 can be mounted to the speed reducer housing 231 in advance, manufacturing becomes very easy.

The decelerator 230 may include an intermediate shaft 241. The conversion means 240 of the reduction gear may comprise said intermediate shaft 241. The intermediate shaft 241 is a shaft 241 for connecting the rotor shaft 220 and the drum shaft 210 to be coaxial, and is configured to rotate independently of the drum shaft 210 and the rotor shaft 220.

The intermediate shaft 241 is inserted into the centers of the rotor shaft 220 and the drum shaft 210, respectively, which shafts are coaxial. Bearings 235 are provided on the outer side of the intermediate shaft 241 and the inner side of the drum shaft 210. The intermediate shaft 241 and the drum shaft 210 may be independently rotated by the bearings 235. A bearing 237 is provided on the outside of the intermediate shaft 241 and the inside of the rotor shaft 220. The intermediate shaft 241 and the rotor shaft 220 may be independently rotated by the bearing 237.

The drum 20, the rear case 130, the power transmission unit, and the driving unit can be assembled very easily.

First, the decelerator 230 and the connector 250 are coupled. The connector 250 is coupled to the rear housing 130. After the stator 280 is coupled to the connector 250, the connector 250 may be coupled to the rear housing 130. Then, the stator 280 is temporarily coupled to the connector 250. The rotor shaft 220 is inserted into and temporarily coupled to the center of the rotor 260, and the drum shaft 210 may be inserted into and temporarily coupled to the center of the drum rear wall 22.

Inside the drum, the rear wall of the drum and the drum shaft 210 are coupled by a stud 291. Further, the rotor 270 and the rotor shaft 220 are coupled by the stud 294 at the outer rear of the rotor 270.

Through the above-described sequence, the combination of the drum 20, the rear housing 130, the power transmission parts 210, 220, 230, and the motor 260 can be easily performed. Then, the flow path pipe 170 is coupled to the rear Fang Waike from the rear of the rear housing 130, and the driving part cover 180 may be coupled to the flow path pipe 170 to protect the driving part 200. Further, after the electric wire or the signal wire is wired to the motor 260, the electric wire or the signal wire may be protected using the electric wire cover 190. One end of the wire cover 190 may be coupled to the rear housing 130 at the outside in the radial direction of the flow path pipe, and the other end thereof may be coupled to the flow path pipe or the rear housing 130 at the inside in the radial direction of the flow path pipe 170. The wire cover 190 may be coupled first, and then the driving part cover 180 may be coupled.

Hereinafter, the drum 20 applicable to the present embodiment will be described in detail with reference to fig. 5 and 6.

Fig. 5 is a front perspective view of the drum, and fig. 6 is a rear front view of the drum.

The drum 20 may include a side wall 21 and a rear wall 22 in the form of an opening at the front thereof. Further, the drum 20 may be formed in a cylindrical structure of which rear is blocked by the rear wall 22. Here, being blocked means that laundry is formed to be illegally put in and out, and air can be communicated.

A mounting region 23 is formed in a central portion of the rear wall 22. The mounting region 23 is a region for mounting the drum shaft 210, and may be a region opposite to the decelerator 230. An air suction area 24 may be formed on the outer side of the mounting area 23 in the radial direction. Further, a rear wall edge region 25 may be formed on the outer side of the air intake region 24 in the radial direction, and the rear wall edge region 25 may be connected to the side wall 21.

When the rear wall 22 is circular, the mounting region 23 is formed so as not to communicate air and to mount the drum shaft at the center, and an air suction region 24 for passing air therethrough may be formed on the outer side of the mounting region 23 in the radial direction.

A plurality of holes 26 are formed in the air suction area 24 so that air is communicated. Specifically, the air intake area 24 is formed in a mesh shape. The wider the air suction area 24 is, the more air can be uniformly supplied to the inside of the drum 20, so that the drying efficiency can be improved. The diameter of the hole 29 is very small. This is because the laundry is prevented from being damaged by being inserted into the hole 26. Therefore, the number of the holes 26 has to be very large so that air is smoothly supplied to the inside of the drum 20.

However, the rigidity of the rear wall 22 may be weakened by the holes 26. Thus, to enhance the rigidity of the rear wall 22 by such an air intake area 24, the air intake area 24 may include a plurality of radius bridges 27 and circumferential bridges 28. The radius bridges 27 may be provided to divide the air intake area 24 in the circumferential direction, and the circumferential bridges 28 may be provided to divide the air intake area 24 into an inner side and an outer side in the radial direction.

The radius bridge 27 may extend from the mounting area 23 through the air intake area 24 to the rear wall edge area 25. Furthermore, the radius bridges 27 may be connected with the circumferential bridges 28.

Holes 26 are preferably not formed in the radius bridges 27 and the circumferential bridges 28. Accordingly, as a support structure for supporting the air suction area 24 of the mesh structure formed by the plurality of holes 26, a radius bridge 27 and a circumferential bridge 28 may be formed. The radius bridges 27 and the circumferential bridges 28 are preferably formed to protrude forward or to protrude rearward to strengthen the rigidity thereof.

Also, the holes 26 are preferably not formed in the rear wall edge region 25. Since the rear wall edge region 25 is connected to the side wall 21, the rigidity of the rear wall edge region 25 is prevented from weakening. In addition, in the case where air flows in from the rear wall edge region 25, the air may be supplied to laundry clinging to the inner side wall of the drum 20, or to a position where no laundry is present. Therefore, in order to improve the drying efficiency, it is preferable to intensively supply air from the air suction area 24 instead of supplying air from the rear wall edge area 25.

A stud hole (stud hole) 29a may be formed at the center of the mounting area 23 at the center of the drum rear wall 22. Further, a spacer (washer) mounting portion 29c may be formed on the outer side in the radial direction around the stud hole 29a. A plurality of bolt fastening portions 29b may be formed on the radially outer side of the spacer mounting portion 29c. Here, in the present embodiment, it may be named a stud, a bolt, or a screw according to the relative size of the fastening device for convenience. Therefore, the fastening device is not limited by a specific name.

The mounting area 23 may be an area fastened to the drum shaft 210. In order to firmly fasten the drum shaft 210 to the drum 20 and to secure reliability of power transmission, a coupling is provided. This may be referred to as a roller coupler 293 (see fig. 3).

In essence, the hot air does not preferably flow into the drum 20 through the central portion of the drum rear wall 20. Therefore, the mounting region 23 preferably extends further radially outward of the roller coupling 293.

Fig. 6 shows the state in which the washers 40, 50 are projected to the drum rear wall 22. The gaskets 40, 50 may be provided for sealing air between the drum rear wall 22 and the rear housing 130. That is, the air flowing into the inside from the outside of the rear case 130 passes through the air suction area 24 and flows into the inside of the drum 20 by the seal formed by the gasket between the drum rear wall 22 and the rear case 130.

The position, structure and function of the washers 40, 50 will be described in detail with reference to fig. 7. Fig. 7 is a cross-sectional view of the drum, the driving part, and the flow path pipe part on the gasket part.

The washers 40, 50 may include an inner washer 40 radially inward and an outer washer 50 radially outward. The inside gasket 40 divides the installation area 23 of the drum 20 and the air suction area 24. Accordingly, the hot air can be prevented from leaking from the outside of the drum 20 toward the direction (radially inward) of the attachment area of the drum 20. The outside gasket 50 divides the air suction area 24 and the rear wall edge area 25 of the drum 20. Accordingly, the leakage of the hot wind from the outside of the drum 20 toward the rear wall edge region 25 of the drum 20 can be prevented.

The inner gasket 40 may include a fixing portion 41 and an extension portion 42, and a fastening portion 43 may be formed at the fixing portion 41. The inner gasket 40 may be mounted to an inner side surface of the rear case 130 by a fixing portion 41 and a fastening portion 43, and the extension portion 42 may be formed to extend from the fixing portion 41 toward the drum rear wall 22. The extension 42 may be placed in contact with the drum rear wall 22, thereby performing a seal. The extending portion 42 may extend obliquely from the outer side toward the inner side in the radial direction. That is, the extension portion 42 may be located radially inward of the fixing portion 41.

Also, the outer gasket 50 may include a fixing portion 51 and an extension portion 52, and a fastening portion 53 may be formed at the fixing portion 51. The outer gasket 50 may be mounted to an inner side surface of the rear case 130 by a fixing portion 51 and a fastening portion 53, and the extension portion 52 may be formed to extend from the fixing portion 51 toward the drum rear wall 22. The extension 52 may be placed in contact with the drum rear wall 22, thereby performing a seal. The extending portion 52 may extend obliquely from the inner side toward the outer side in the radial direction. That is, the extension portion 52 may be located radially outward of the fixing portion 51.

The extension portions 42, 52 of the inner and outer washers 40, 50 may both extend obliquely from the fixing portions 41, 51 toward the drum rear wall 22. Thereby, it is possible to minimize friction between the rotating drum 20 and the ends of the extensions 42, 52 and perform sealing against air.

Of course, unlike the above, the washers 40, 50 may be mounted to the drum 20 instead of the rear housing 130. However, it is preferable that the gasket is mounted to the rear housing 130 that has been fixed, not the drum 20 as a structure to be rotated. Thus, not only is it easy to manufacture, but also the sealing site can be formed in the lower part (down stream) of the flow path of air instead of in the upper part (up stream), thus facilitating sealing more.

Further, as shown in fig. 7, the power transmission portion may be located in the closed space. As an example, the motor and the decelerator including the stator 280 and the rotor 260 may be located inside a space surrounded by the rear housing 130, the flow path pipe 170, and the driving part cover 180.

The decelerator and the motor, particularly the stator, may generate heat as the drum is driven, and elimination of such heat is very advantageous in ensuring performance. Therefore, it is preferable to add a structure for heat dissipation or cooling.

It is possible to secure cooling performance by utilizing natural convection or convection generated by rotation of the rotor, instead of adding a separate structure such as a cooling fan.

The rotor 260 may be formed with a plurality of openings 260a, and air may flow into the rotor 260 from the outside of the rotor 260 as the rotor 260 rotates. The inflowing air may flow toward the stator 280.

Further, the air flowing into the rotor 260 is preferably external air. For this purpose, the driving unit cover 180 may be provided with a plurality of openings 180a, and the plurality of openings 180a may be provided.

The air flowing in from the opening 180a of the driving part cover 180 passes through the opening 260a of the rotor and cools the stator inside the rotor. Here, it is necessary to discharge the air cooled by the rotor to the outside so as to generate efficient circulation or flow of the air. Therefore, the driving unit cover 180 preferably has a discharge unit 180b for discharging air to the outside.

As shown in fig. 7, with this structure, the flow of air is generated, whereby effective cooling can be performed.

Here, the opening 260a of the rotor and the opening 180a of the driving part cover 180 are preferably positioned opposite to each other. Accordingly, the flow resistance of the air can be minimized. On the other hand, in the case where air flows in from the outside, an excessively high inflow pressure is not preferable. Therefore, the number of the openings 180a and the total area of the openings are preferably larger than the number of the openings of the rotor and the total area of the openings.

In addition, the inflow portion position of the air and the discharge portion position of the air in the driving portion cover 180 are preferably different from each other to smoothly perform inflow and discharge of the air. That is, the position of the discharge portion is preferably located radially outward of the position of the inflow portion.

Therefore, an opening for allowing air to flow in and out is easily formed in the driving part cover 180, so that the motor and the decelerator can be cooled effectively.

The air flow path of the dryer according to an embodiment of the present application will be described in detail with reference to fig. 8 and 9.

An exhaust port 131 for exhausting air from the inside to the outside of the dryer may be formed at the rear housing 130. Further, an inflow port 135 for allowing air discharged through the discharge port 131 to flow into the inside of the dryer may be formed at the rear housing 130. The outlet 131 is a single outlet, and the inflow port 135 may be formed in plural.

The inflow port 135 may be formed at an air supply region 134 of the rear case 130, and the air supply region 134 may be formed at a radially outer side of the installation region 136. The air supply area 134 may be formed to surround the mounting area 136.

The discharge port 131 may be formed at an air suction area of the rear housing 130. The air intake region may be disposed radially outward of the air supply region 134. The discharge port 131 may be formed as a single discharge port, and thus may be referred to as an air suction area.

The air flowing into the inside of the flow path pipe 170 through the outlet 131 flows into the inside of the dryer through the inlet 135. Specifically, air passing through the inflow port 135 may pass between the drum rear wall 22 sealed by the gasket 40, 50 and the rear case front and flow into the inside of the drum 20.

The inflow port 135 is preferably formed to be larger than the size of the hole 26 for flowing air into the inside of the drum 20 to reduce the resistance of the air flowing in through the inflow port 135. As shown, the number of holes 26 of the drum projected to one inflow port 135 may be 10 or more.

The region in which the holes 26 of the drum are formed may be continuously formed along the circumferential direction except at the radius rib 27. In contrast, the inflow port 135 and the inflow port 135 may be disposed to be spaced apart from each other in the circumferential direction. The area of the portion of the air inflow region 134 where the inflow port 135 is formed may be similar to the area of the portion where the inflow port 135 is not formed.

The width of the inflow port 135 in the radial direction is preferably smaller than the width of the drum in the radial direction of the air intake area 24. That is, the area of sucking air from the drum is preferably larger than the area for supplying air to the drum from the rear housing. This makes it possible to more smoothly perform the air inflow and to uniformly flow the air into the drum.

The flow path duct 170 may be provided to cover all of the air suction area 131 and the air supply area 134 of the rear housing 130 except for the installation area of the rear housing 130. Accordingly, the air flowing into the inside of the flow path duct 170 through the air suction region 131 can be branched to both sides of the installation region and flow along the periphery of the installation region, and can be discharged from the flow path duct through the inflow port 134.

The air discharged through the inflow port 135 flows into the drum through the plurality of holes 29 formed in the air suction region 24 formed in the drum rear wall 22. The air flowing into the drum is discharged to the front of the drum, passes through the heat pump 300 and the fan 179, and is discharged to the outside of the rear housing 130 of the dryer through the discharge port 131 of the rear housing 130.

On the other hand, although not shown, the heat pump 300 may be replaced with a heating unit. That is, the configuration for condensing the moisture in the air may be omitted. That is, the air outside the dryer is flowed into the dryer and then heated,

With this structure, in the dryer of the present embodiment, drying can be performed while circulating air. May include: a fan 179 for generating a circulating flow of air; a heat pump 300 as an example of a structure for heating and condensing air; and a flow path pipe 170 and a connection pipe 179 for forming a flow path of air.

In addition, a fan mounting portion 132 protruding rearward may be provided at the rear case 130. The discharge port 131 may be formed at the fan mounting portion 132. Further, a wire drawing hole 133 may be formed at an upper portion of the rear housing 130.

The flow path pipe 170 may include an inner coupling portion 172 and an outer coupling portion 171. The inside coupling portion 172 may be coupled with the rear housing 130 between the mounting region and the air supply region of the rear housing 130. The outside coupling portion 171 may surround the air supply area and the air suction area of the entire rear case 130 and be coupled with the rear case 130. An expansion 173 is formed between the outer coupling portion 171 and the inner coupling portion 172, thereby forming an air flow space 171.

The expansion 173 may be formed to protrude rearward from the rear housing 130. Therefore, the electric wire extending to the outside of the rear case 130 through the electric wire drawing hole 133 needs to be connected to the motor located radially inward of the inner joint 172 of the flow path pipe 170, across the expansion 173. Accordingly, the wire cover 133 for protecting the crossing wire also crosses the expanding portion 173. The front-rear width of the dryer may be increased by such a wire cover 133. Therefore, it is preferable that a seating portion 173 is formed at a portion of the expansion portion 173, which is recessed toward the front, thereby seating the wire cover.

Between the air supply area 134 and the mounting area 136 of the rear housing 130, a wire bonding area or a wire cover bonding area 137 may be formed. The wire bonding area 137 may be an area where a part of the mounting area 136 is expanded to the outside in the radial direction. Therefore, the radial width of the inflow port 135 formed outside the wire bonding region in the radial direction may be narrowed by the wire bonding region 137.

The flow path pipe may be formed with a wire bonding area corresponding to the wire bonding area of the rear case 130. One end of the wire cover 190 may be fixedly coupled through the wire coupling region.

As described above, the dryer of an embodiment of the present application preferably includes the decelerator 230. The reason why the reduction gear is required and the optimal reduction ratio in one embodiment of the present application will be described below with reference to fig. 10.

In DIRECT DRIVE type devices, an outer rotor type motor in which permanent magnets are provided to a rotor is widely used in order to easily control torque and RPM of the motor. In order to apply such an outer rotor type motor to the present embodiment, it is necessary to check the efficiency of the motor. The efficiency of the motor based on the current phase angle is shown in fig. 10, where the motor uses 269W of power consumption.

As shown in the drawings, it can be seen that the efficiency of the outer rotor type motor is high in a high speed operation region, for example, in a region of 600 to 750 RPM. However, in a low-speed operation around 50RPM, which is a general driving RPM of the dryer drum, efficiency is significantly reduced, or the drum itself is not rotated due to insufficient torque. That is, there may be a case where the drum cannot be driven. For this reason, there is a need for a decelerator capable of driving a motor at an RPM having an optimal efficiency and driving a drum at approximately 50 RPM. Therefore, in the present embodiment, as an example, a reduction ratio of 15 may be provided: 1. The optimal reduction ratio may vary due to differences in the motor itself and differences in the drum drive RPM, but is approximately equal to 15:1 are similar.

In general, a reduction gear using a planetary gear is manufactured for the purpose of reducing the speed of a sub motor or the like, and is fastened to the front surface of the motor. Therefore, the limitation of the motor to the outer diameter of the reduction gear is generally in the form of securing a safety factor by increasing the thickness of the planetary gear (the axial length of the gear).

However, in the decelerator of the dryer of an embodiment of the present application, a compact design for the height (axial length) may be required as compared to the outer diameter of the decelerator. This is because the motor in the present embodiment is an outer rotor type motor, and thus the outer diameter of the decelerator can be maximally close to the outer diameter of the rotor.

To achieve a higher reduction ratio (e.g., 15:1), a two-stage planetary-gear type reducer may be employed. One-stage planetary-style reducers are generally at 9:1, and 15 in the first-stage planetary gear type speed reducer due to the geometric feature of the reduction mechanism: the number of planetary gears with a reduction ratio of about 1 is two. Thus, the stability is very poor. Therefore, in the present embodiment, in order to achieve a high reduction ratio and ensure safety, a two-stage planetary gear type speed reducer that performs speed reduction by four planetary gears in the primary speed reduction, with the result that the secondary speed reduction is performed, may be applied.

On the other hand, in the case of using a secondary gear, the thickness (axial length of the reduction gear) is increased by the gear, and therefore a compact and lightweight design is highly required. In this embodiment, a speed reducer that converts a high RPM low torque secondary to a low RPM high torque may be provided between the rotor and the drum. Further, in consideration of the power conversion characteristics in the dryer, a speed reducer that is compact and capable of achieving light weight can be provided.

In the primary power conversion, the thickness of the gear can be reduced in consideration of the characteristic that the torque of the input shaft (rotor shaft in the present embodiment) is low. In addition, the gear may be formed of an engineering plastic such as polyoxymethylene (POM: poly Oxy Methylene) based material instead of a steel based material. Therefore, by reducing the thickness and weight of the gear in proportion to the strength of the gear, a compact and lightweight design can be achieved.

However, in the secondary power conversion, the torque of the output shaft (the drum shaft in the present embodiment) is in a state that is increased by the primary power conversion, and thus higher gear strength is required. Therefore, in the secondary power conversion, it is preferable to relatively increase the height of the gear, and to form the gear from steel.

In view of this, in particular, there is a thickness of the gear for power conversion in the secondary power conversion, and it may be difficult to realize a compact speed reducer.

In an embodiment of the present application, improvement in gear strength by increasing the outer diameter of the gear is focused instead of improvement in gear strength by increasing the thickness of the gear.

The overall outer diameter of the planetary gear is increased with the same reduction ratio and the same ratio constitution, whereby the gear strength can be increased. This is because, in gears having the same number of gear teeth, if the outer diameter increases, the support area of the gear teeth increases. In other words, the support area of the gear teeth can be increased by increasing the size of the gear teeth, instead of increasing the thickness of the gear.

The strength of such gears ensures that it can be applied not only to primary power conversion but also to secondary power conversion as well. Thus, a very compact front-to-back reduction can be achieved in all primary and secondary gears having the same outer diameter. In particular, since the decelerator in the present embodiment converts the power of the outer rotor type motor, the outer diameter of the decelerator can be sufficiently allowed to increase. In particular, the outer diameter of the decelerator may be increased corresponding to the inner diameter of the hollow part 250a of the connector fixing the stator to the rear housing.

Hereinafter, a decelerator and a deceleration principle according to an embodiment of the present application will be described in detail with reference to fig. 11 to 13. Fig. 11 is an exploded perspective view of the decelerator, fig. 12 shows a connection structure of the decelerator for primary conversion of power, and fig. 13 shows a connection structure of the decelerator for secondary conversion of power.

The decelerator 230 may include a housing 231, and the housing 231 may include a front housing 231a and a rear housing 231b. Inside the housing 231, a configuration for various conversion devices may be accommodated. A fastening portion 231c may be provided in the housing 231. The rear housing 231b may be substantially configured to accommodate the conversion device, and the front housing 231a may perform a cover function of covering the rear housing 231b. Of course, the opposite may be true.

When the rear housing 231b is substantially configured to accommodate the conversion device, the fastening portion 231c may be provided at the rear housing 231b. The rear housing 231b is inserted into the hollow portion 250a of the connector 250, and is fixedly coupled to the connector 250 by the fastening portion 231 c.

A through hole 233 of the rotor shaft 220 is formed in a central portion of the rear housing 231b, and a bearing 236 rotatably supporting the rotor shaft 220 is provided in the through hole 233.

A through hole 232 of the drum shaft 210 is formed in a central portion of the front housing 231a, and a bearing 234 rotatably supporting the drum shaft 210 is provided in the through hole 232.

The input RPM in the primary power conversion may be referred to as a high RPM. Accordingly, the bearing 336 supporting the rotor shaft 220 is preferably a ball bearing. Also, the ball bearings are preferably provided in two along the rotor shaft 220. The output RPM in the two-stage power conversion may be referred to as a low RPM. Therefore, the bearings for supporting the drum shaft 210 are preferably oil-free bearings. That is, this is to ensure reliability and reduce manufacturing costs.

The power of the rotor 260 is directly transmitted to the rotor shaft 220. The rotor shaft 220 is securely coupled to the rotor 260 by a rotor coupling 296, shims 295, and studs 194. One side of the rotor shaft 220 may be combined with the rotor and the other side may form a first sun gear 221. Accordingly, the rotor shaft 220 and the first sun gear 221 may be one component or structure. May be formed of a single material.

The same first planetary gear 223 is provided on the outer side in the radial direction of the first sun gear 221, and the first sun gear and the first planetary gear are meshed together. If the first planetary gears are provided with the same interval along the circumferential direction of the first sun gear, as an example, four first planetary gears may be provided.

The first planetary gear 223 may be rotatably provided with reference to a roller shaft (roller shaft) 222, and the roller shaft 222 may be fixed to the first bracket 243. In order to achieve the fixation of the front-rear position of the first planetary gear and the fixation of the roller shaft, a first stand support 224 may be provided. Accordingly, the first planetary gear 223 may be rotatably provided to the first bracket 243, and the first bracket 243 rotates as the first planetary gear 223 revolves around the first sun gear 221.

The first planetary gears 223 may be meshed with the ring gear 244 in an inscribed manner.

In the case where the reduction ratio in each step is set to a, and the ring gear 244 is provided to be fixed inside the housing 231 of the reduction gear, a has a value added to 1 at the value of the number of gear teeth of the ring gear 244 divided by the number of teeth of the sun gear.

If motor power is input to the rotor shaft 220 at N RPM and T torque, the first sun gear 221 has the same N RPM and T torque.

As the rotor shaft 220 rotates, the first planetary gears 223 and the first bracket 243 also rotate. At this time, the first bracket 243 has a reduction ratio of a, an RPM of N/a, and a torque of t×a. Thus, the power of the rotor shaft 220 may be first-stage converted through the first bracket 243.

A first planetary gear 223 is rotatably provided on one side (rotor shaft side) of the first bracket 243. Further, a second sun gear 242 may be provided on the other side (drum shaft side) of the second bracket 243. The second carrier 243 and the second sun gear 242 may be integrally formed as a single component. Accordingly, the second bracket 243 and the second sun gear 242 integrally rotate. Accordingly, the second sun gear 242 has a reduction ratio of a, an RPM of N/a, and a torque of T x a.

As the second sun gear rotates, the second planetary gears 213 and the second carrier 211 also rotate. The second planetary gear 213 may be rotatably provided to the second bracket 211 by a roller shaft 212. In order to achieve the fixation of the front-rear position of the second planetary gear 213 and the fixation of the roller shaft 212, a second carrier support 214 may be provided.

As the second planetary gears 213 revolve around the second sun gear 242, the second carrier 211 rotates.

At this time, the second bracket 211 has a value of a reduction ratio a, RPM N/a/a, and torque ta.

The second bracket 211 may be combined with the drum shaft 210. Preferably, the second bracket 211 and the drum shaft 210 may be provided as a single component or constructed. Thus, the drum shaft 210 has an RPM of N/a/a and a torque of Ta.

As described above, the reduction ratio of the speed reducer in the present embodiment is 15:1. thus, in the case where the first-stage reduction ratio and the second-stage reduction ratio both have the same value of a, the value of a may have a square root of 15, i.e., a value of 3.871.

Here, it is very effective to set the first-stage reduction ratio to a and the second-stage reduction ratio to a, and finally to have a reduction ratio of the square value of a. This is because the ring gear for the deceleration of the first stage and the second stage can be realized by a single ring gear. That is, the rear of the fixed single ring gear may mesh with the first planetary gears and the front of the single ring gear may mesh with the second planetary gears. Therefore, the decelerator can be realized very easily.

In addition, the planetary gear and the carrier have the same radius. Thus, a reduction gear having a cylindrical shape and the same front-rear diameter can be realized. Of course, except for the fastening portion structure for the fixed coupling of the decelerator.

The drum shaft 210 may be fixedly secured to the drum rear wall by a drum shaft coupler 293, shims 292, and studs 291.

As a result, according to the present embodiment, the decelerator 230 may be disposed between the rear wall of the drum and the inner side wall of the rotor, converting the high RPM low torque of the rotor into the low RPM high torque of the drum.

Further, the rotor shaft 220 and the drum shaft 210 are spaced apart from each other in the front-rear direction. It is necessary to make the rotor shaft 220 and the drum shaft 210 coaxial and to firmly maintain the coaxial.

For this purpose, an intermediate shaft 241 may be provided. One side of the intermediate shaft 241 may be connected to and formed coaxially with the rotor shaft 220, and the other side may be connected to and formed coaxially with the drum shaft 210.

The intermediate shaft 241 may be integrally formed with the first bracket 243 and the second sun gear 242. That is, it may be constructed as a single structure or component. Accordingly, the intermediate shaft 241 may be integrally rotated with the first bracket 243. This means that the rotational speed of the first carrier is different from the rotational speed of the rotor shaft and the drum shaft, respectively.

Therefore, a structure is required that is supported in such a manner that the intermediate shaft 241, the drum shaft 210, and the rotor shaft 220 can be rotated at different rotational speeds from each other, or in such a manner that they can be rotated independently from each other. Of course, such a support structure may be referred to as a structure for forming and maintaining coaxiality.

The intermediate shaft 241 is inserted into and located at the center of the drum shaft 210 and the center of the rotor shaft 220. A hollow may be formed at a portion of the drum shaft and the rotor shaft so as to insert the intermediate shaft. Bearings 235 may be provided between the drum shaft and the intermediate shaft, and likewise bearings 237 may be provided between the rotor shaft and the intermediate shaft.

The thrust generated between the rotor 260 and the drum rear wall 22 may be supported by the bearings 236, 234 described above. As an example, the oil-free bearing 234 may be supported by bringing a step formed on the outer periphery of the side drum shaft and an annular ring (not shown in fig. 10) fastened to the side surface of the ball bearing 236 and the shaft into contact. Therefore, friction caused by the thrust force at the driving portion or the power transmitting portion can be minimized.

On the other hand, a reduction gear of a form different from that of the planetary gear reduction gear in the above-described embodiment of the present application may also be applied to the dryer of the embodiment of the present application. As an example, a cycloidal pin gear (cyclic) reducer may be applied.

The cycloidal pin gear speed reducer is a speed reducer using a speed reducer having cycloidal pin gear tooth shapes. Wherein the gear teeth are shaped as a continuous curve of cycloidal pin tooth profiles and are in rolling contact. Since the input shaft and the output shaft may be formed coaxially, the present embodiment can also be applied.

According to the dryer of an embodiment of the present application, uniform drying can be performed. As shown in fig. 14, it can be seen that there is a uniform air flow velocity in the dryer of an embodiment of the present application regardless of the front and rear positions of the drum.

The standard deviation of the velocity refers to a deviation of the air flow velocity in the entire cross section at the cross section position of the drum. A small standard deviation of velocity means that the velocity variation is not large over the whole area of a specific section.

Thus, according to the present embodiment, the standard deviation of the velocity at 7 cross-sectional positions between the front surface and the rear surface of the drum is substantially 0.7 or less, and it can be seen that all but the rear surface of the drum is substantially 0.6 or less. The inflow of air at the rear surface of the drum is performed only on a predetermined area, so that the result can be predicted.

However, in the existing dryer having a structure in which air flows in from the rear of the drum, it can be seen that the speed standard deviation increases significantly according to the sectional position of the drum. In particular, it can be seen that the standard deviation of velocity is greater in all positions than in the present application. In addition, it can be seen that the standard deviation of the velocity becomes significantly higher near the rear of the drum. This shows in contrast that the standard deviation of velocity in an embodiment of the application becomes significantly lower behind the drum.

It is presumed that the speed standard deviation characteristic of such a dryer of an embodiment of the present application is caused by the annular air supply area of the rear casing and the annular air suction area of the rear wall of the drum. That is, the position where the air flows into the drum is the same regardless of whether the drum is rotated or not and the rotation speed of the drum, and thus it can be presumed that the drum has such characteristics. Further, it is presumed that the area where air flows into the inside of the drum and the area where air is supplied toward the drum are increased as compared with the conventional dryer.

In particular, according to the present embodiment, it can be seen that air can flow into the inside of the drum through the entire 360 degrees. Therefore, it can be seen that more air quantity can be supplied to the inside of the drum, and air can be uniformly supplied. In addition, according to the dryer of the present embodiment, the drying efficiency can be improved, and uniform drying can be performed.

Claims

1. A dryer, wherein the dryer comprises:

A housing configured to form an external appearance of the dryer and to support the dryer;

A drum disposed inside the housing and accommodating a drying object;

a driving part configured to drive the drum and including a motor having a stator and a rotor;

a drum shaft connected to the rear of the drum;

A rotor shaft connected to the rotor; and

A decelerator configured to transmit a rotational force of the rotor shaft to the drum shaft,

The housing includes a rear housing forming a rear appearance of the dryer and supporting,

The rotor is rotatably supported on the rear housing outside the rear housing coaxially with the rotation axis of the drum,

The rear housing is provided in a plate shape facing the rear surface of the drum,

The stator is fixed to the rear housing at an outer side of the rear housing,

The rear housing is disposed between the drum and the decelerator,

The drum is configured to be separated from a side of the rear housing,

The decelerator is disposed outside the rear case so as to be separated from the drum.

2. The dryer of claim 1, wherein the dryer further comprises a dryer housing,

The motor is an outer rotor type motor provided so that the rotor rotates radially outward of the stator.

3. The dryer of claim 1, wherein the dryer further comprises a dryer housing,

The stator has a hollow portion on the inner side in the radial direction thereof and is fixed to the outer side of the rear housing.

4. The dryer as claimed in claim 3, wherein,

Comprising a connector disposed between the stator and the rear housing and configured to secure the stator to the rear housing and to form a front-rear space therebetween.

5. The dryer of claim 4, wherein the drying unit comprises a dryer,

A portion of the connector is inserted into the hollow of the stator.

6. The dryer of claim 4, wherein the drying unit comprises a dryer,

The connector has a hollow portion on the inner side in the radial direction thereof.

7. The dryer of claim 6, wherein the dryer further comprises a dryer housing,

The decelerator converts the high RPM low torque of the rotor into the low RPM high torque of the drum,

At least a portion of the decelerator is inserted into and positioned in the hollow portion of the connector.

8. The dryer of claim 1, wherein the dryer further comprises a dryer housing,

The rear housing has a shaft through hole formed therein, and the drum shaft penetrates the shaft through hole.

9. The dryer of claim 8, wherein the dryer further comprises a dryer housing,

The speed reducer includes:

A housing; and

And a conversion device provided inside the case and converting the high RPM low torque of the rotor into the low RPM high torque of the drum.

10. The dryer of claim 9, wherein the dryer further comprises a dryer housing,

The housing of the speed reducer is arranged to be fixed to the outside of the rear housing.

11. The dryer as claimed in claim 10, wherein,

The housing of the speed reducer includes:

A drum shaft through hole protruding forward by a predetermined length so that the drum shaft passes through the drum shaft through hole, and a bearing rotatably supporting the drum shaft is mounted in the drum shaft through hole; and

A rotor shaft through hole protruding rearward by a predetermined length so that the rotor shaft passes through the rotor shaft through hole, and a bearing rotatably supporting the rotor shaft is mounted in the rotor shaft through hole.

12. The dryer of claim 11, wherein the dryer further comprises a dryer housing,

The drum shaft through hole is inserted into and positioned at the shaft through hole of the rear housing,

The rotor shaft through hole is inserted into and located in a hollow portion of the stator formed radially inward.

13. The dryer as claimed in any one of claims 1 to 12, characterized in that,

A shaft through hole is formed in the rear case, a drum shaft connected to the drum and transmitting power of the rotor to the drum penetrates the shaft through hole,

The rear housing has a mounting region for mounting the drive unit on the outer side in the radial direction around the shaft through hole.

14. The dryer of claim 13, wherein the dryer further comprises a dryer housing,

An air supply area for supplying air to the inside of the drum is formed at the rear housing,

The air supply region is formed radially outward of the mounting region with the mounting region as a center.

15. The dryer of claim 14, wherein the dryer further comprises a dryer housing,

An air suction area for sucking air from the drum is formed at the rear housing,

The air intake region is formed radially outward of the air supply region.

16. The dryer of claim 15, wherein the dryer further comprises a dryer housing,

Comprises a flow path duct which is provided to be coupled to the rear housing at an outer side of the rear housing and covers the air suction area and the air supply area to form an air flow space between the flow path duct and the rear housing.

17. The dryer of claim 13, wherein the dryer further comprises a dryer housing,

An air suction area of a circular ring shape is formed at a rear wall of the drum, the air suction area being opposite to an air supply area of the rear housing.

18. The dryer of claim 17, wherein the dryer further comprises a dryer housing,

Comprises a gasket disposed between the rear case and the rear wall of the drum such that air supplied from an air supply area of the rear case flows into an air suction area of the drum.