EP2327828A1

EP2327828A1 - Clothes drying machine having a heater, and related heater

Info

Publication number: EP2327828A1
Application number: EP10190946A
Authority: EP
Inventors: Jihao Li; Zhihua Yan
Original assignee: BSH Bosch und Siemens Hausgeraete GmbH
Current assignee: BSH Hausgeraete GmbH
Priority date: 2009-11-25
Filing date: 2010-11-12
Publication date: 2011-06-01
Anticipated expiration: 2030-11-12
Also published as: CN102071564A; EP2327828B1; CN102071564B

Abstract

According to the invention, a heater 70 and a clothes drying machine 100 using the same are provided. The clothes drying machine 100 includes a cabinet 10, a drum 30 mounted in the cabinet 10 for containing clothes to be dried, an air duct 60 in communication with the drum 30 to enable an air flow to pass through and into the drum for drying the clothes, and a heater 70 provided with a baffle 711 to disturb the air flow passing by to produce a turbulent flow. With the inventive structure, hot air about to enter the drum 30 may be mixed completely, so that heat exchange performance of the hot air is improved.

Description

The present invention relates to a clothes drying machine having a heater, and a heater related to such clothes drying machine.
In an existing clothes drying machine, such as a dryer or a washer-dryer having functions of washing and drying in one, a drying process is usually as follows. With a heater, dry air is heated by a heater in an air duct into dry hot air, enters a clothes processing drum to exchange heat with wet clothes, take moisture away from the clothes, become wet hot air, and pass through an outlet disposed at the drum to enter a condenser in the air duct. By condensation, moisture in the wet hot air is condensed into water and discharged through a drainage device. After the condensation, the air becomes dry cold air, is guided to the heater again by a blower, becomes dry hot air after heating, and enters another cycle as detailed. The cycle repeats until the drying is completed.
Normally, an air flow flowing through the air duct is laminar, so that after being heated by the heater temperature of the air flow in different layers is not the same. The temperature of the air flow layer near the heating substructures of the heater is higher, and the temperature of the air flow layer away from these substructures (such as near side walls of the air duct) is lower. Therefore, heat exchange efficiency of hot air entering the clothes processing drum may be low.
In order to solve that problem in the prior art, the air flows of different layers are pre-mixed before entering the clothes processing drum, so that overall temperature distribution of the hot air is uniform. For example, a baffle plate is disposed on a side wall of an air duct to disturb the air flow layers passing by to produce a turbulent flow, so as to mix the air. However, because temperature of the air flow layers near the side wall is low, the mixture of the air flow layers near the side wall dose not greatly improve overall heat exchange performance of the hot air. In addition, if the size of the air duct is large, the air flow layers in a central area of the air duct or the air flow layers near an opposite side wall can not be mixed completely. Accordingly, it is necessary to improve the existing clothes drying machine to solve the above problems.
In accordance with the invention there are specified a clothes drying machine and a heater related to such machine, which are provided for heating an air flow and disturbing the air flow to produce a turbulent flow, in accordance with the respective independent claim. Preferred embodiments of the invention are subjects of dependent claims and the subsequent description. Preferred embodiments of the inventive machine correspond to preferred embodiments of the inventive heater, even if not specified explicitly herein.
In order to achieve the above object, the present invention provides a clothes drying machine, which includes a cabinet; a drum, mounted in the cabinet for containing clothes to be dried; an air duct, in communication with the drum to define an air path through which an air flow passes and into the drum for drying the clothes; and a heater, disposed in the air duct for heating the air flow about to flow into the drum, and disposed with a baffle to disturb the air flow passing by to produce a turbulent flow.
As a preferred embodiment of the present invention, the baffle is formed by deforming a body of the heater.
As another preferred embodiment of the present invention, the heater has an upstream end and a downstream end, and the baffle is positioned at the downstream end of the heater.
As a further preferred embodiment of the present invention, the heater includes a first heating tube winding and defining a first plane, and the baffle is formed by means of bending a distal end thereof at an angle with respect to the first plane.
As yet another preferred embodiment of the present invention, the heater further includes a second heating tube winding and defining a second plane substantially parallel to the first plane, and the baffle is bent toward the second plane.
As yet a further preferred embodiment of the present invention, the air duct includes a plurality of side walls connected to each other to enclose the heater, and at least one side wall of the plurality of side walls is disposed with a projection disturbing the air flow passing by to produce a turbulent flow.
As still another preferred embodiment of the present invention, the clothes drying machine further includes a condensation device for condensing the air flow flowing from the drum.
As still a further preferred embodiment of the present invention, the clothes drying machine further includes a blower, disposed in the air duct for enabling air to circulate along the air path, and the heater is positioned in the downstream of the blower.
As again another preferred embodiment of the present invention, the clothes drying machine is a dryer or a washer-dryer.
As again a further preferred embodiment of the present invention, the first heating tube includes a plurality of segments extending in a direction substantially parallel to the air path.
In order to achieve the above object, the present invention also provides a heater, applied to a clothes drying machine. The heater is disposed with a baffle for disturbing the air flow passing by to produce a turbulent flow.
As a preferred embodiment of the present invention, the baffle is formed by deforming a body of the heater.
As another preferred embodiment of the present invention, the heater has an upstream end and a downstream end, and the baffle is positioned at the downstream end.
As a further preferred embodiment of the present invention, the heater includes a first heating tube winding and defining a first plane, and the baffle is formed by means of bending a distal end thereof at an angle with respect to the first plane.
As yet another preferred embodiment of the present invention, the heater further includes a second heating tube winding and defining a second plane substantially parallel to the first plane, and the baffle is bent toward the second plane.
Compared with the prior art, beneficial effects of the present invention include the following. The heater is disposed with the baffle, so the air flow layers of high temperature near the heater are mixed first, and are then further mixed with the air flow layers near side walls of the air duct, so that overall heat exchange performance of the hot air in the air duct is ensured to be high. Furthermore, a projection is further disposed on the side walls of the air duct to enhance the mixture of the air flow layers near the projection and the air layers near the heater, so as to further enhance the heat exchange performance of the hot air about to enter the drum.
Preferred embodiments are now described with references to the attached drawing. In the drawing,

FIG. 1 is a schematic plane view of a clothes drying machine;
FIG. 2 is a schematic plane view of a heater;
FIG. 3 is a schematic working view of the heater in FIG. 2 applied to the clothes drying machine in FIG. 1; and
FIG. 4, similar to FIG. 3, discloses another embodiment in which a heater is applied to a clothes drying machine.

A clothes drying machine 100 shown in FIG. 1 is a washer-dryer 100 having functions of washing and drying. Definitely, it should be understood that the clothes drying machine 100 may also be a dryer only having a drying function or other machines. Therefore, the implementation of the present invention is described below by taking a washer-dryer 100 as an example, but the present invention is not limited thereto.
As shown in FIG. 1, a washer-dryer 100 includes a cabinet 10, a tub 20 disposed in the cabinet, a drum 30 rotatably disposed in the tub 20, a motor 40 for driving the drum 30 to rotate, a drainage system 50, 51 in communication with the tub 20, and an air duct 60 in communication with the drum. A front part of the cabinet 10 is disposed with a door 11 capable of being opened and closed in a pivotable manner for inputting clothes to be washed or to be dried into the drum 30. Normally, the tub 20 is supported by a damping device (not shown) in the cabinet 10. The drum 30 is substantially cylindrical, and a wall thereof is disposed with a plurality of through holes (not shown) for discharging water or air. Usually, an inner wall of the drum 30 is further disposed with a plurality of lifting ribs (not shown) distributed along the circumference, so that the clothes are lifted to a higher place and then dropped to the bottom inside the drum when the drum rotates. A rotation shaft (not marked) extends from a rear wall of the drum 30, and a strap 41 connects the rotation shaft to a motor shaft (not marked) of the motor 40, so that the motor 40 can drive the drum 30 to rotate. The drainage system 50, 51 includes a drainage pump 50 and a drainage tube 51, so that washing water can be discharged from the cabinet 10 by the operation of the drainage pump 50.
In this embodiment, the air duct 60 is in double communication with the drum 30 to form an air path substantially closed in itself. A blower 80 is disposed in the air duct 60, and can produce a blowing force and a suction force, so as to drive the air flow to flow along the air path, as indicated by arrows. The air duct 60 includes a condensation section 61 and a heating section 62. A heater 70 is disposed in the heating section 62 to heat the air flow passing through the heating section 62 and about to enter the drum 30. In this embodiment, an air condenser 90 is disposed in the condensation section 61, which air condenser 90 includes a plurality of first ducts (not marked and perpendicular to the drawing) and second ducts (not marked and parallel to the air path) intersecting but not in communication with each other. The first ducts allow external air to pass through, and the second ducts allow wet air discharged from the drum 30 to pass through. With the structure, moisture in the wet air of high temperature can be condensed into water completely, thus achieving a good condensation effect. It should be obvious that, the condensation device may also be a spraying device disposed in a condensation area or a liquid condensation device capable of performing heat exchange with the condensation area.
Referring to FIG. 2 and FIG. 3, in this embodiment, the heater 70 is substantially positioned in a central area of the heating section 62, and is located in the downstream of a blower 82. The heater 70 includes a first heating tube 71 and a second heating tube 72, which are distributed one above the other and parallel to each other. The first heating tube 71 is under the second heating tube 72, and is formed by a plurality of winding segments and substantially parallel to the air path, and the plurality of segments defines a fist plane. The second heating tube 72 also includes a plurality of winding segments and substantially parallel to the air path, and the plurality of segments defines a second plane substantially parallel to the first plane. But in an extension direction of the air path, the second heating tube 72 is shorter than the first heating tube 71. It should be known that the heating tubes 71 and 72 include high-impedance conductors, and negative and positive terminals of the conductors are connected to a 220 V or 110 V alternating current power supply through wires, so that the conductors can transform electricity into heat energy to heat the air passing along.
In this embodiment, a downstream end of the first heating tube 71 is bent at an angle with respect to the first plane toward the second plane to form a baffle 711. In the embodiment as shown in FIG. 2 and FIG. 3, the baffle 711 is positioned at an arcuate transition end at a distal end of the first heating tube 71, and the number of the baffles 711 is 3, which are disposed horizontally. The baffle 711 is for changing directions of air flow layers (including air flow layers shown in FIG. 2 distributed horizontally and air flow layers shown in FIG. 3 distributed vertically) passing by to produce a turbulent flow, so that air flows in different layers are mixed to improve the overall heat exchange performance of hot air. In this embodiment, because the first heating tube 71 is positioned in a lower place in the heating section 62, the baffle 711 is bent upward. It should be understood that if the first heating tube 71 is disposed in a higher place in the air duct, it is better for the baffle 711 to be bent downward. In addition, the baffle 711 may also be bent in a horizontal direction to enhance mixture of the air flow layers in the horizontal direction. The bending angle may be determined by a vertical size or a horizontal size of the air duct 60. If the vertical or horizontal size is large, the bending angle may better be large, so that more air flows are mixed. Furthermore, the same baffle 711 may also be formed at a distal end of the second heating tube 72, or a third heating tube or a fourth heating tube with the same baffle 711 may be added above the second heating tube 72 or below the first heating tube 71. Since the heater 70 is usually disposed in a central area of the heating section, the baffle 711 disposed on the body of the heater 70 can enable the air flow layers of high temperature near the heater 70 be mixed first, and then further be mixed with the air flow layers near side walls 621 and 622 of the air duct 60, so that overall heat exchange performance of the hot air in the air duct 60 is ensured to be high. Although in this embodiment, the baffle 711 is integrally formed at the distal end of the body of the heater 70, in other embodiments, the baffle 711 may disposed on the heater 70 by assembly, such as by traditional fixing methods of welding or buckling. Additionally, the disposition location of the baffle 711 is not limited to the downstream end of the heater 70, and may be at other places on the body of the heater 70.
Referring to FIG. 3, in another embodiment, since a structure of a heater 70 is identical with that of the heater 70 in the above embodiment, the reference numerals of the parts of the heater 70 are kept consistent with those in the above embodiment. The difference lies in that, a projection 6251 projected into the air duct 60 is further disposed on an upper side wall 625 of the heating section 62. The projection 6251 also has the same function of disturbing the air flow, so that the air flow layers near the upper side wall 625 can be further mixed with the air flow layers near the heater 70 completely. Thereby, further improving the heat exchange performance of the hot air about to enter the drum 30 are attained. The projection 6251 may be integrally formed on the upper side wall 625, or may be installed on the side wall 625. Additionally, projections may further be disposed on other side walls, such as a lower side wall 626, to enhance mixture of the air flow layers nearby and the air flow layers near the heater.

Claims

A clothes drying machine (100) comprising:
a cabinet (10);

a drum (30) mounted in the cabinet (10) for containing clothes to be dried;

an air duct (60) connected with the drum (30) to define an air path through which a laminar air flow passes about and into the drum (30) for drying the clothes;

a heater (70) disposed in the air duct (60) for heating the laminar air flow, said heater (70) generally extending along the air path and having a baffle (711) to break up and mix the laminar air flow.
The clothes drying machine according to claim 1, wherein said baffle (711) is formed by deforming a body of the heater (70).
The clothes drying machine according to one of the preceding claims, wherein said heater (70) has an upstream end (701) and a downstream end (702), wherein said baffle (711) is positioned at the downstream end (702).
The clothes drying machine according to one of the preceding claims, wherein said heater (70) comprises a first heating tube winding (71) and defining a first plane, and wherein said baffle (711) is formed by means of bending a distal end of the heater (70) at said first heating tube winding (71) at an angle with respect to the first plane.
The clothes drying machine according to claim 4, wherein said heater (70) further comprises a second heating tube winding (72) and defining a second plane substantially parallel to the first plane; wherein said baffle (711) is bent towards the second plane.
The clothes drying machine according to claim 5, wherein said air duct (60) comprises a plurality of side walls (625, 626) connected to each other to enclose the heater (70), and at least one (625) of said side walls provides a projection (6251) projected towards the baffle (711).
The clothes drying machine according to one of the preceding claims, further comprising a condensation device (90) associated with the air duct (60) for condensing air withdrawn from the drum (30).
The clothes drying machine according to one of the preceding claims, further comprising a blower (80) disposed in the air duct (60) for enabling air to circulate along the air path, wherein said heater (70) is positioned downstream from the blower (80).
The clothes drying machine according to one of the preceding claims, wherein said clothes drying machine (100) is a dryer (100) or a washer-dryer (100).
A heater (70) for a drying machine (100), the heating machine (100) comprising a cabinet (10), a drum (30) mounted in the cabinet (10) for containing clothes to be dried, and an air duct (60) connected with the drum (30) to define an air path through which a laminar air flow passes and into the drum (30) for drying the clothes; said heater (70) comprising a baffle (711) for breaking up and mixing the laminar air flow.
The heater (70) according to claim 10, wherein said baffle is formed by deforming a body of the heater (70).
The heater (70) according to one of claims 10 and 11, wherein said heater (70) has an upstream end (701) and a downstream end (702), wherein said baffle (711) is positioned at the downstream end (702).
The heater (70) according to one of claims 10 to 12, wherein said heater (70) comprises a first heating tube winding (71) and defining a first plane, and wherein said baffle (711) is formed by means of bending a distal end of the heater (70) at said first heating tube winding (71) at an angle with respect to the first plane.
The heater (70) according to claim 13, further comprising a second heating tube winding (72) and defining a second plane substantially parallel to the first plane; wherein said baffle (711) is bent towards the second plane.