# Patent

## Title
Washing machine and control panel assembly thereof

## Abstract

Disclosed is a washing machine, a control panel assembly of which has an improved structure to minimize problems caused by a shaking of a rotary knob and the interference of the rotary knob with other surrounding parts. The control panel assembly of the washing machine includes a control panel, a knob guide installed on the control panel, and a rotary knob rotatably mounted on the knob guide and including a boss passing through the knob guide. The knob guide includes a boss insertion part restricting the boss to prevent the rotary knob from shaking. The boss insertion part includes an extension extended from the bottom surface of the knob guide and forming a boss insertion hole, into which the boss is inserted, therein.

## Background
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation application of U.S. Ser. No. 14/270,571 filed in the United States on May 6, 2014, which is a continuation application of U.S. Ser. No. 12/071,797 filed in the United States on Feb. 26, 2008 that is now patented as U.S. Pat. No. 8,752,405 B2, and claims the priority benefit of Korean Patent Application No. 10-2007-0050632 filed May 25, 2007 in the Korean Intellectual Property Office, the disclosures of which are incorporated herein by reference.


BACKGROUND
1. Field
The present invention relates to a washing machine, and more particularly, to a washing machine, a control panel assembly which has an improved structure to minimize problems caused by a shaking of a rotary knob and an interference of the rotary knob with other surrounding parts.
2. Description of the Related Art
Washing machines are apparatuses that wash clothes using electric power. In general, a washing machine includes a tub storing washing water, and a drum rotatably installed in the tub. When the drum is rotated or a pulsator installed in the drum is rotated under the condition that laundry and washing water containing a detergent are put into the drum, the laundry rubs against the drum and the washing water, thus being washed.
The washing machine further includes a control panel assembly installed on an upper end of a front surface of a main body forming the external appearance of the washing machine to control the operation of the washing machine. FIG. 1 is an exploded perspective view of a control panel assembly of a conventional washing machine.
The control panel assembly of the washing machine shown in FIG. 1 includes a substrate 3, on which various electric components, such as a rotary switch 1 and LEDs 2, are installed, and a control panel 4 covering the substrate 3 to protect the substrate 3 and provided with an opening 4a formed through one side thereof. A decoration window 5 is installed at the opening 4a of the control panel 4. The decoration window 5 transmits light irradiated from the LEDs 2, and is provided with a through hole 5a to pass a rotary knob 6 therethrough. An encoder bracket 7 covering the LEDs 2 to protect the LEDs 2 is installed on the substrate 3, and the rotary knob 6 is connected to a rotary shaft 1a of the rotary switch 1 installed on the substrate 3. When the control panel 4 and the substrate 3 are assembled, the rotary knob 6 is protruded forward from the control panel 4 through the through hole 5a of the decoration window 5.
In such a control panel assembly, when a user manipulates the rotary knob 6, the rotary knob 6 shakes and thus provides an unpleasant feeling to the user. That is, since the rotary switch 1 is fixed to the substrate 3 having a small thickness, the rotary knob 6, which is assembled with the rotary switch 1, is easily shaken together with the rotary switch 1. This problem can be solved by reducing the size of the through hole 5a to allow the decoration window 5 to prevent the shaking of the rotary knob 6. However, in this case, when the rotary knob 6 is manipulated, the rotary knob 6 interferes with the decoration window 5 and thus cannot be smoothly rotated, or the rotary knob 6 provides an unpleasant feeling to the user. Further, noise due to friction occurs.
SUMMARY
Therefore, one aspect of the embodiment is to provide a washing machine, which minimizes a shaking of a rotary knob, and a control panel assembly thereof.
Another aspect of the embodiment is to provide a washing machine, which minimizes problems caused by an interference of a rotary knob with other surrounding parts, and a control panel assembly thereof.
Additional aspects and/or advantages will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the invention.
The foregoing and/or other aspects are achieved by providing a washing machine having a control panel assembly to control an operation of the washing machine, the control panel assembly including a control panel; a knob guide installed on the control panel and including a boss insertion part; and a rotary knob rotatably mounted on the knob guide and including a boss passing through the knob guide, wherein the boss insertion part restricts the boss to prevent the rotary knob from shaking.
The boss insertion part may include an extension extended from a bottom surface of the knob guide and forming a boss insertion hole, into which the boss is inserted, therein.
An inner surface of the extension forming the boss insertion hole may be inclined such that a distance between the inner surface of the extension and the boss gradually increases from a point at which the extension abuts the boss.
A diameter of the boss insertion hole may be varied in an extended direction of the extension.
The rotary knob may include a connection part connected to the knob guide when the rotary knob is mounted on the knob guide; and the knob guide may include a restriction part restricting the connection part of the rotary knob.
The connection part may include at least one hook protruded towards the knob guide and connected to the knob guide when the rotary knob is mounted on the knob guide, and the restriction part may include at least one hook protruded towards the rotary knob and restricting the rotary knob when the rotary knob is mounted on the knob guide.
The connection part may include first hooks protruded towards the knob guide, and the restriction part may include second hooks protruded towards the rotary knob and engaged with the first hooks of the connection part.
The foregoing and/or other aspects are achieved by providing a control panel assembly of a washing machine including a rotary knob including a boss protruded therefrom; and a knob guide including a base panel to pass the boss through a central portion thereof, and an extension extending from the base panel to restrict the boss.
The extension may be inclined such that a distance between the extension and the boss gradually decreases in an extended direction of the extension to a point at which the extension abuts the boss.
The rotary knob may include first hooks protruded towards the knob guide, and the knob guide may include second hooks protruded towards the rotary knob and engaged with the first hooks when the boss of the rotary know is passed through the central portion of the base panel of the knob guide.
Drain holes to drain water flowing from an outside to the base panel may be formed through the base panel.
The foregoing and/or other aspects are achieved by providing a washing machine, including: a drum to receive laundry to be washed; and a control panel assembly, including: a rotary knob including a boss extending therefrom; and a knob guide receiving the boss and including an angled extension contacting the received boss to restrict the boss.
The angled extension may abut the boss at an abutting point and angle away from the boss from the abutting point to increase a diameter of a boss insertion hole formed between the angled extension and the boss.
The knob guide may include a restriction part and the rotary knob may include a connection part, the restriction part and the connection part being engaged to fix the rotary knob to the knob guide when the boss is received by the knob guide.
At least one of the knob guide and the rotary knob may include a connection part and an other of the knob guide and the rotary knob may include connection holes formed through the other of the knob guide and the rotary knob, the connection part being received into the connection holes to affix the rotary knob and the knob guide to one another.
The foregoing and/or other aspects are achieved by providing a washing machine, including: a drum to receive laundry to be washed; and a control panel assembly, including: a rotary knob including a connection part extending therefrom; and a knob guide including a restriction part extending therefrom, wherein the connection part and the restriction part are engaged to fix the rotary knob to the knob guide.
The rotary knob may include a boss extending therefrom and the knob guide receives the boss and includes an angled extension contacting the received boss to restrict the boss.
The angled extension may abut the boss at an abutting point and angle away from the boss from the abutting point to increase a diameter of a boss insertion hole formed between the angled extension and the boss.



BRIEF DESCRIPTION OF THE DRAWINGS
These and/or other aspects and advantages will become apparent and more readily appreciated from the following description of the embodiment, taken in conjunction with the accompanying drawings in which:
FIG. 1 is an exploded perspective view of a control panel assembly of a conventional washing machine;
FIG. 2 is a perspective view of a washing machine in accordance with a present embodiment;
FIG. 3 is an exploded perspective view of a control panel assembly of the washing machine in accordance with the present embodiment;
FIG. 4 is a sectional view of the control panel assembly of the washing machine in accordance with the present embodiment; and
FIGS. 5A to 5C are views illustrating a process of assembling the control panel assembly of the washing machine in accordance with the present embodiment.



DETAILED DESCRIPTION OF THE EMBODIMENTS
Reference will now be made in detail to the embodiment, an example of which is illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. The embodiment is described below to explain the present invention by referring to the annexed drawings.
FIG. 2 is a perspective view of a washing machine in accordance with the present embodiment.
As shown in FIG. 2, the washing machine in accordance with the present embodiment includes a main body 10 forming an external appearance of the washing machine, a tub (not shown) installed in the main body 10 to store washing water, and a drum 12 rotatably installed in the tub to wash laundry. An opening 13 is formed through a front surface of the main body 10 so that a user can put laundry into an inside of the tub through the opening 13, and a door 14 to open and close the opening 13 is installed. A control panel assembly 100 to control an operation of the washing machine is provided on an upper portion of the front surface of the main body 10.
FIG. 3 is an exploded perspective view of the control panel assembly of the washing machine in accordance with the present embodiment, and FIG. 4 is a sectional view of the control panel assembly of the washing machine in accordance with the present embodiment. As shown in FIGS. 3 and 4, the control panel assembly 100 includes a control panel 110 provided with an opening 111 formed through one side thereof, and a circuit board 120 installed in the control panel 110.
A rotary switch 121 is installed on the circuit board 120, and a plurality of LEDs 122 is installed on the circuit board 120 around the rotary switch 121. The rotary switch 121 includes a push shaft 121a protruded forwardly, and a rotary shaft 121b surrounding a lower portion of the push shaft 121a. A knob assembly 150 including a rotary knob 160 and a push button 151 is assembled with the rotary switch 121. A user rotates the rotary shaft 121b of the rotary switch 121 or presses the push shaft 121a of the rotary switch 121 through the rotary knob 160 and the push button 151, and thus is capable of selecting a function, such as a washing course or a washing time.
An encoder bracket 130, provided with cylindrical cell parts 131 respectively covering the LEDs 122 to protect the LEDs 122 and guiding light irradiated from the LEDs 122 forwardly is installed on the circuit board 120. A through hole 132 to pass the rotary shaft 121b and the push shaft 121a of the rotary switch 121 is formed through a central portion of the encoder bracket 130.
A knob guide 140 is installed at the opening 111 of the control panel 110, and the knob assembly 150 is mounted on a front surface of the knob guide 140. The knob guide 140 serves to support the knob assembly 150 to prevent the knob assembly 150 from shaking, and to display a function, selected by rotating or pressing the knob assembly 150, to the user.
The knob guide 140 includes a base panel 141, on which the knob assembly 150 is mounted, a ring-shaped display panel 142 formed along a circumference of the base panel 141, and protrusions 143 formed along a circumference of the display panel 142. Letters or marks are printed on the display panel 142 so that the user can recognize the function selected by the knob assembly 150. The display panel 142 has light transmission parts 142a to transmit the light irradiated from the LEDs 122 of the circuit board 120 in a forward direction. The protrusions 143 are fastened to an edge of the opening 111 when the knob guide 140 is installed on the control panel 110. Drain holes 141a to drain water flowing from the outside into the base panel 141 are formed through the base panel 141.
The knob assembly 150 includes the rotary knob 160 rotatably mounted on the base panel 141 of the knob guide 140, the push button 151 disposed on the rotary knob 160, and a button cover 152 covering an edge of the push button 151.
The rotary knob 160 includes a knob body 161 having a button reception part 161a to receive the push button 151 formed on an upper portion thereof and a circumferential surface 161b to be held by a user when the operation of the washing machine is controlled, and a boss 162 protruded downwardly from a central portion of the knob body 161. A shaft insertion hole 163 is formed in the boss 162, and a connection protrusion 163a connected with the rotary shaft 121b of the rotary switch 121 is provided in the shaft insertion hole 163. The connection protrusion 163a is connected to a connection groove 121c of the rotary shaft 121b when the rotary shaft 121b of the rotary switch 121 is inserted into the shaft insertion hole 163. A button shaft 151a of the push button 151 is also inserted into the shaft insertion hole 163. The button shaft 151a inserted into the shaft insertion hole 163 is connected to the push shaft 121a of the rotary switch 121 in the shaft insertion hole 163. Thus, the user can operate the rotary switch 121 by rotating the rotary knob 160 or pushing the push button 151, thereby selecting a desired function.
The knob body 161 of the rotary knob 160 is seated on the base panel 141 of the knob guide 140, and the boss 162 of the rotary knob 160 passes through the base panel 141 and is extended downwardly. The knob guide 140 further includes a boss insertion part 170, which restricts the boss 162 to prevent the rotary knob 160 from shaking. Since the boss insertion part 170 prevents the rotary knob 160 from shaking, as described above, when the rotary knob 160 and the knob guide 140 contact each other, an area of friction therebetween is reduced. That is, when a conventional rotary knob rubs against surrounding parts, the circumferential surface of the body of the rotary knob rubs against the surrounding parts. However, in the present embodiment, the boss 162, which has a relatively small diameter, rubs against the boss insertion part 170, and thus noise and malfunction caused by the friction are reduced.
The boss insertion part 170 is provided with an extension 170a extended upwardly from the base panel 141 of the knob guide 140. A boss insertion hole 171, into which the boss 162 of the rotary knob 160 is inserted, is formed within the extension 170a. Although this embodiment illustrates the extension 170a extended upwardly, the extension 170a is not limited thereto and thus may be extended downwardly from the base panel 141, for example.
An inner surface of the extension 170a, which forms the boss insertion hole 171, is provided with an inclined surface 171a such that a distance between the inner surface of the extension 170a and the boss 162 gradually increases. That is, the extension 170a is provided with the inclined surface 171a such that a diameter of at least a part of the boss insertion hole 171 in an extended direction of the extension 170a is varied. The inclined surface 171a causes contact of the boss 162 of the rotary knob 160 with the extension 170a of the knob guide 140, which is similar to line contact, and thus an area of friction between the boss 162 and the extension 170a when the boss 162 and the extension 170a rub with each other is minimized.
The rotary knob 160 includes a connection part 164, which is connected to the knob guide 140, and the knob guide 140 includes a restriction part 144, which restricts the connection part 164. The connection part 164 and the restriction part 144 serve to allow the rotary knob 160 to be rotatably mounted on the knob guide 140 and to prevent the rotary knob 160 from being separated from the knob guide 140 when the user pulls the rotary knob 160.
The connection part 164, as shown in FIG. 4, may include at least one hook 164a (hereinafter, referred to as a ‘first hook’) protruded from a rear surface of the button reception part 161a toward the knob guide 140. Further, the restriction part 144 may include at least one hook 144a (hereinafter, referred to as a ‘second hook’) protruded from the base panel 141 toward the rotary knob 160 to be engaged with the first hook 164a. 
Although FIG. 3 illustrates three first hooks 164a and three second hooks 144a respectively provided in the circumferential directions of the rotary knob 160 and the knob guide 140, the number of the first hooks 164a and the second hooks 144a may be properly modified as the occasion demands in terms of design.
Further, although FIG. 4 illustrates the rotary knob 160 connected to the knob guide 140 by the engagement between the first hooks 164a and the second hooks 144a, the rotary knob 160 may be connected to the knob guide 140 by hooks, which are formed on one of the rotary knob 160 and the knob guide 140, and connection holes, which are formed through the other one of the rotary knob 160 and the knob guide 140 such that the hooks are inserted into the connection holes. Here, the connection holes must have a ring shape in consideration of the rotation of the rotary knob 160.
Hereinafter, a process of assembling the control panel assembly of the washing machine in accordance with the present invention will be described with reference to FIG. 3 and FIGS. 5A to 5C.
First, as shown in FIG. 5A, when the knob guide 140 is inserted into the opening 111 of the control panel 110 from the rear of the control panel 110, the display panel 142 and the base panel 141 are exposed from the front surface of the control panel 110 to the outside through the opening 111. The encoder bracket 130 is assembled with the circuit board 120 to protect the rotary switch 121 and the LEDs 122 installed on the circuit board 120. Here, the push shaft 121a and the rotary shaft 121b of the rotary switch 121 are protruded forward from the encoder bracket 130 through the through hole 132 of the encoder bracket 130.
Thereafter, as shown in FIG. 5B, the circuit board 120 is fixed to the control panel 110 on which the knob guide 140 is installed by fastening members, such as screws. Then, the push shaft 121a and the rotary shaft 121b of the rotary switch 121 are exposed from the front surface of the control panel 110 to the outside through the boss insertion part 170 of the knob guide 140.
Thereafter, as shown in FIG. 5C, the rotary knob 160 is assembled with the knob guide 140 from the front of the control panel 110. Here, the boss 162 of the rotary knob 160 is inserted into the boss insertion part 170, and the first hooks 164a of the rotary knob 160 are engaged with the second hooks 144a of the knob guide 140. When the boss 162 of the rotary knob 160 is inserted into the boss insertion part 170, the rotary shaft 121b of the rotary switch 121 is inserted into the shaft insertion hole 163 formed in the boss 162, and thus is connected to the boss 162. Finally, the push button 151 is assembled with the button reception part 161a of the rotary knob 160. Here, the button shaft 151a of the push button 151 is connected to the push shaft 121a of the rotary switch 121 in the shaft insertion hole 163. When the assembling of the push button 151 with the button reception part 161a is completed, the button cover 152 is put on the push button 151, thus finishing the appearance of the knob assembly 150.
As apparent from the above description, the present embodiment provides a washing machine that prevents a rotary knob from shaking, and a control panel assembly thereof, thereby providing a comfortable feeling to a user manipulating the rotary knob and thus improving the reliability of a product.
Further, even when the rotary knob interferes with a surrounding knob guide, the area of friction between the rotary knob and the knob guide is minimized. Thus, noise and malfunction caused by the friction are minimized.
Although an embodiment has been shown and described, it would be appreciated by those skilled in the art that changes may be made in this embodiment without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents.

## Claims

1. A laundry machine comprising:
a main body;
a circuit board provided in the main body;
a rotary switch on the circuit board to allow a user to select one of a plurality of laundry programs while rotating and having a shaft protruding forwardly;
a plurality of LEDs (light emitting diodes) provided on the circuit board around the rotary switch and where each of the LEDs respectively indicates the one of the plurality of programs selected by the rotary switch;
a rotary knob having a knob body and a boss protruding from a central portion of the knob body; and
a knob guide encompassing at least a part of the boss to support the boss when the knob is used,
wherein at least a part of the knob guide is formed in a shape where an inner diameter of a surface of the knob guide facing the boss increases away from a boss insertion opening.

2. The laundry machine according to claim 1, further comprising:
wherein the knob guide comprises a base part, an extension part extended from the base, and the boss insertion opening formed at a one end of the extension part, and an inner diameter of the extension part gradually increases from the boss insertion opening to an other end of the extension part.

3. The laundry machine according to claim 1, further comprising a bracket covering the LEDs, the bracket having a plurality of windows to respectively protect the LEDs and the bracket having a through hole formed in central portion of the bracket.

4. The laundry machine according to claim 3, wherein the knob guide comprises a base panel to pass the boss through a central portion thereof, and an extension extending from the base panel, and the boss insertion opening is formed at one end of the extension.

5. The laundry machine according to claim 4, wherein the knob guide further comprises a display panel formed along a circumference of the base panel, and the display panel comprises one of printed letters and marks so that the user can recognize the one of the plurality of programs selected by the rotary switch.

6. The laundry machine according to claim 4, wherein the display panel has light transmission parts to transmit the light irradiated from the LEDs of the circuit board forwardly.

7. The laundry machine according to claim 3, wherein the knob guide being disposed on a central portion of the bracket.

8. The laundry machine according to claim 1, further comprising a control panel disposed in front of the main body and the control panel is provided with an opening through which the boss passes.

9. The laundry machine according to claim 1, wherein a diameter of the boss is smaller than a diameter of the boss insertion opening to minimize contact between the boss and boss insertion opening.

10. The laundry machine according to claim 1, wherein the knob guide comprises a stabilization structure to prevent the rotary knob from shaking.

11. The laundry machine according to claim 10, wherein the stabilization structure provides support for the knob boss.

12. The laundry machine according to claim 10, wherein the rotary knob has a button end and an end opposite a button and the stabilization structure is positioned closer to the button end than the end opposite the button.

13. A laundry machine comprising:
a main body;
a circuit board provided in the main body;
a rotary switch on the circuit board to allow a user to select one of a plurality of laundry programs while rotating and having a shaft protruding forwardly;
a rotary knob having a knob body and a boss protruding from a central portion of the knob body; and
a stabilization structure having a boss insertion opening,
wherein a portion of the stabilization structure is formed in a shape where an inner diameter of a surface of the portion facing the boss decreases toward the boss insertion opening to reduce rotary knob shaking.

14. The laundry machine according to claim 13, wherein the stabilization structure prevents the knob from shaking.

15. The laundry machine according to claim 14, wherein the rotary knob has a button end and an end opposite a button, the stabilization structure provides support for the knob boss and the stabilization structure is positioned closer to the button end than the end opposite the button in association with the knob boss.

16. A laundry machine comprising:
a main body;
a circuit board provided in the main body having a plurality of LEDs (light emitting diodes) to indicate a selected laundry program;
a rotary switch on the circuit board to allow a user to select one of a plurality of laundry programs while rotating and having a shaft protruding forwardly, the plurality of LEDs being provided around the rotary switch;
a rotary knob having a knob body and a boss protruded from a central portion of the knob body; and
a support structure having a boss insertion opening,
wherein a portion of the support structure is formed in a shape where an inner diameter of a surface of the portion facing the boss decreases toward the boss insertion opening to provide lateral support to the rotary knob during movement thereof.

17. The laundry machine according to claim 16, wherein the support structure prevents the knob from shaking.

18. The laundry machine according to claim 17, wherein the support structure is near a top of the rotary knob.