KR0149907B1

KR0149907B1 - Water dispenser of a refrigerator

Info

Publication number: KR0149907B1
Application number: KR1019950052136A
Authority: KR
Inventors: 오길수
Original assignee: 김광호; 삼성전자주식회사
Priority date: 1995-12-19
Filing date: 1995-12-19
Publication date: 1999-05-01
Also published as: KR970047529A

Abstract

본 발명은 냉장고의 음료공급장치에 관한 것으로, 그 목적은 그 구조를 간단히하여 설치가 용이하도록 하고 청소를 용이하게 할 수 있도록 하여 양호한 위생상태를 유지시킬 수 있으며, 음료통을 도어가 아닌 저장실에 수납시키도록 하여 음료통의 용량을 확대시킬 수 있도록 하는 것이다.The present invention relates to a beverage supply device of the refrigerator, the object of which is to simplify the structure and to facilitate the installation and to facilitate the cleaning can maintain a good hygiene state, the beverage container in the storage compartment rather than the door It is to be stored so that the capacity of the beverage container can be expanded.

본 발명은, 그 내부에 냉장실(11)이 마련된 본체(10), 냉장실(11)을 개폐하는 도어(20), 냉장실(11)에 수납되는 음료통(30), 음료통(30)으로부터 음료를 공급받도록 도어(20)의 외측면에 인입형성된 취출공간(21), 취출공간(21)과 음료통(30)사이에 마련되며 도어(20)의 닫힘시 결합되어 음료통(30)에 저장된 음료의 배출을 제어하는 수단을 포함하여 구성된다.The present invention is a beverage from the main body 10 having the refrigerating chamber 11 provided therein, the door 20 opening and closing the refrigerating chamber 11, the beverage container 30 accommodated in the refrigerating chamber 11, and the beverage container 30. It is provided between the take-out space 21, the take-out space 21 and the beverage container 30 formed in the outer side of the door 20 so as to receive the supply and coupled to the closing of the door 20 is stored in the beverage container 30 And means for controlling the discharge of the beverage.

Description

Beverage supply device of refrigerator

제1도는 일반적인 음료공급장치를 보인 단면도이다.1 is a cross-sectional view showing a general beverage supply device.

제2도는 본 발명에 따른 음료공급장치가 채용된 냉장고의 내부를 보인 도면이다.2 is a view showing the inside of a refrigerator employing a beverage supply apparatus according to the present invention.

제3도는 제2도에 도시된 본 발명에 따른 음료공급장치의 도어 닫힘시의 도면이다.3 is a view when the door of the beverage supply device according to the invention shown in FIG.

제4도는 본 발명에 따른 음료공급장치의 작동상태로서, a는 닫힘시, b는 열림시를 도시한 것이다.4 is an operating state of the beverage supply apparatus according to the present invention, a is shown when closed, b is shown when opened.

* 도면의 주요부분에 대한 부호의 설명* Explanation of symbols for main parts of the drawings

10 : 본체 11 : 냉장실10: body 11: refrigerator

20 : 도어 21 : 취출공간20: door 21: ejection space

30 : 음료통 31 : 배수부30: beverage container 31: drain

41 : 설치관 42 : 유로41: installation pipe 42: euro

43 : 결합안내관 51 : 제1밀폐부재43: coupling guide 51: first sealing member

52 : 제2밀폐부재 61 : 제1작동부재52: second sealing member 61: the first operating member

62 : 제2작동부재 70 : 레버62: second operating member 70: lever

81 : 가스킷81: gasket

본 발명은 냉장고의 음료공급장치에 관한 것으로, 특히 음료통을 냉장실에 수납시키고 도어의 닫힘시 서로 연동되는 작동부재와 밀폐부재를 도어와 음료통에 각각 설치하여 음료통의 음료를 도어의 외부에서 인출할 수 있는 냉장고의 음료공급장치에 관한 것이다.The present invention relates to a beverage supply apparatus of the refrigerator, and in particular, the beverage container is accommodated in the refrigerating chamber, and the operating member and the sealing member interlocked with each other when the door is closed, respectively installed in the door and the beverage container to drink the beverage in the beverage container outside the door. It relates to a beverage supply device of the refrigerator that can be withdrawn.

제1도는 일반적인 냉장고의 음료공급장치를 보인 도면이다. 이에 도시한 바와 같이, 냉장고 도어(1)에는 상하로 형성되어 도어(1)의 내부와 외부를 연통시키는 설치공(9)이 형성되고, 설치공(9)의 내부에는 중공의 설치관(2)이 결합설치된다. 설치관(2)의 상부에는 음료통(3)이 도치상태로 결합되고, 설치관(2)의 내부에는 그 내부에 상하로 연통되어 공기가 흡입되는 흡입유로(7)가 형성된 중공의 유로관(4)이 승강가능하게 설치된다. 이때 유로관(4)은 물이 배출되는 배출유로(8)를 형성하기 위하여 설치관(2)의 내측면으로부터 일정간격 이격되어 설치된다. 유로관(4)의 외곽에는 배출유로(8)와 흡입유로(7)를 개폐하는 개폐관(5)이 설치되는데, 개폐관(4)은 흡입유로(7)를 먼저 개방시킨후 배출유로(8)를 개방시키도록 유로관(4)에 일정폭 상하유동하도록 설치된다. 그리고 설치관(2)과 유로관(4) 사이에는 유로관(4)을 탄성복원시키는 스프링(6)이 설치된다.1 is a view showing a beverage supply device of a general refrigerator. As shown in the figure, an installation hole 9 is formed in the refrigerator door 1 and is formed up and down to communicate the inside and the outside of the door 1, and inside the installation hole 9, a hollow installation tube 2 ) Is installed in combination. The upper part of the installation pipe (2) is connected to the beverage container (3) in the inverted state, and the inside of the installation pipe (2) is a hollow flow path tube formed with a suction flow path (7) in which air is sucked up and down inside the installation pipe (2) (4) is installed to be movable. At this time, the flow path pipe 4 is installed spaced apart from the inner surface of the installation pipe (2) to form a discharge flow path (8) through which water is discharged. The opening and closing pipe 5 for opening and closing the discharge flow path 8 and the suction flow path 7 is installed outside the flow path pipe 4, and the opening and closing pipe 4 opens the suction flow path 7 first and then discharges the flow path ( It is provided to flow up and down a certain width in the flow path 4 to open 8). A spring 6 for elastically restoring the flow path tube 4 is installed between the installation pipe 2 and the flow path tube 4.

이와 같이 구성된 종래 냉장고의 음료공급장치의 음료취출과정은 다음과 같다. 유로관(4)의 하단부를 상측으로 밀면, 유로관(4)이 상승하면서 흡입유로(7)를 개방시킨후, 개폐관(5)과 함께 상승하여 배출유로(8)를 개방시킨다. 이렇게 개방된 흡입유로(7)로 공기가 흡입되면서 배출유로(8)를 통하여 음료가 배출되는 것이다.The beverage taking process of the beverage supply device of the conventional refrigerator configured as described above is as follows. When the lower end portion of the flow path pipe 4 is pushed upward, the flow path pipe 4 rises to open the suction flow path 7, and then rises together with the opening and closing pipe 5 to open the discharge flow path 8. As air is sucked into the open suction channel 7, the beverage is discharged through the discharge channel 8.

그러나 이와 같은 종래 냉장고의 음료공급장치는, 음료의 배출을 제어하는 구조가 다수개의 중공관으로 이루어져 제조와 설치공정이 난해한 문제가 있었다. 또한 그 직경이 작은 중공관의 내부를 청소하기 힘들어 장치의 청결도가 떨어져 비위생적인 문제가 있었다.However, the conventional beverage supply apparatus of the refrigerator has a problem that the manufacturing and installation process is difficult because the structure for controlling the discharge of the beverage is composed of a plurality of hollow tubes. In addition, it is difficult to clean the inside of the hollow tube with a small diameter, the cleanliness of the device was unsanitary problem.

또한 음료통이 도어의 내부 상측에 수용설치되기 때문에 용량을 크게 할 수 없어 음료를 자주 공급해야 함으로써 번거러움이 따랐다.In addition, because the beverage container is housed on the upper side of the door, the capacity cannot be increased, and the drink has to be frequently supplied.

따라서 본 발명은 상기한 문제를 해결하기 위한 것으로, 본 발명의 목적은 그 구조를 간단히하여 설치가 용이하도록 하고 청소를 용이하게 할 수 있도록 하여 양호한 위생상태를 유지시킬 수 있는 냉장고의 음료공급장치를 제공하는 것이다.Therefore, the present invention is to solve the above problems, an object of the present invention is to provide a beverage supply apparatus of the refrigerator which can maintain a good hygiene state by simplifying the structure to facilitate installation and easy cleaning To provide.

본 발명의 다른 목적은 음료통을 도어가 아닌 저장실에 수납시키도록 하여 음료통의 용량을 확대시키는 냉장고의 음료공급장치를 제공하는 것이다.It is another object of the present invention to provide a beverage supply apparatus of a refrigerator which expands the capacity of the beverage container by storing the beverage container in the storage compartment instead of the door.

상기 목적을 달성하기 위한 본 발명은, 그 내부에 저장실이 마련된 본체, 저장실을 개폐하는 개폐하는 도어, 저장실에 수납되는 음료통, 음료통으로부터 음료를 공급받도록 도어의 외측면에 인입형성된 취출공간, 취출공간과 음료통사이에 마련되며 도어의 닫힘시 결합되어 음료통에 저장된 음료의 배출를 제어하는 수단을 포함하는 구성이다.The present invention for achieving the above object is, the main body is provided with a storage compartment, the door to open and close the storage compartment, the beverage container accommodated in the storage compartment, the take-out space formed in the outer side of the door to receive the beverage from the beverage container, It is provided between the take-out space and the beverage container and is coupled to the closing of the door is configured to include a means for controlling the discharge of the beverage stored in the beverage container.

이하에서는 첨부도면을 참조하여 본 발명의 바람직한 실시예를 상세하게 설명하겠다.Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention.

제2도는 본 발명에 따른 음료공급장치가 채용된 냉장고의 내부를 보인 도면이다. 이에 도시한 바와 같이, 전면이 개방된 사각통상의 본체(10)의 내부에는 저장실이 마련된다. 저장실은 중간격(12)에 의하여 냉동실(미도시)과 냉장실(11)로 상하 구획되고, 냉장실(11)의 우측 본체(10)에는 도어(20)가 결합설치되어 냉장실(11)을 개폐할 수 있도록 한다. 냉장실(11)의 상부에는 지지판(13)이 설치되고, 지지판(13)의 상측에는 음료가 저장된 음료통(30)이 수용설치된다.2 is a view showing the inside of a refrigerator employing a beverage supply apparatus according to the present invention. As shown in the drawing, a storage chamber is provided inside the rectangular cylindrical body 10 having a front surface open. The storage compartment is divided up and down into a freezing compartment (not shown) and the refrigerating compartment 11 by the intermediate space 12, and the door 20 is coupled to the right main body 10 of the refrigerating compartment 11 to open and close the refrigerating compartment 11. To help. A support plate 13 is installed at an upper portion of the refrigerating chamber 11, and a beverage container 30 storing beverages is installed at an upper side of the support plate 13.

그리고 제3도와 제4도의 a와 b에 도시한 바와 같이, 음료통(30)에 대향하는 도어(20)의 외측면에는 내측으로 인입형성된 취출공간(21)이 설치되고, 취출공간(21)과 음료통(30)의 배수부(31)사이에는 음료통(30)에 저장된 음료를 취출공간(21)으로 배출시키는 구조가 제공된다. 먼저 도어(20)에는 취출공간(21)과 도어(20)의 내부 냉장실(21)을 연통시키는 설치홀(22)이 전후로 형성된다. 이 설치홀(22)에는 그 내부에 전후로 연통된 유로(42)가 형성된 설치관(41)이 결합설치되는데, 이 설치관(41)의 내측단부에는 결합안내관(43)이 결합설치되어 도어(20)의 닫힘시 배수부(31)가 결합설치되도록 한다. 한편 유로(42)는 전단부가 하측으로 굴곡되어 취출공간(21)과 연통된다.3 and 4, the outer side of the door 20 facing the beverage container 30 is provided with a draw-out space 21 inwardly formed, the take-out space 21, as shown in a and b of FIG. Between the drain portion 31 of the beverage container 30 is provided with a structure for discharging the beverage stored in the beverage container 30 to the take-out space 21. First, the installation hole 22 which communicates the taking-out space 21 and the internal refrigerating chamber 21 of the door 20 is formed in the door 20 back and forth. The installation hole 22 is provided with an installation tube 41 having a flow path 42 communicated back and forth inside the installation hole 22, the coupling guide tube 43 is coupled to the inner end of the installation tube 41 to the door When the closing of the 20, the drain 31 is to be coupled to install. On the other hand, the flow path 42 is bent downward to communicate with the take-out space 21.

유로(42)의 내부에는 유로(42)를 개폐하는 제1밀폐부재(51)가 설치된 제1작동부재(61)가 전후왕복운동 가능하게 삽입설치되고, 배수부(31)에는 배수부(31)를 개폐하는 제2밀폐부(52)가 설치된 제2작동부재(62)가 제1작동부재(61)와 함께 전후왕복 운동하도록 설치되어 음료통(30)에 저장된 음료의 배출을 제어한다.The first operating member 61 provided with the first sealing member 51 for opening and closing the flow passage 42 is inserted into the flow passage 42 so as to be movable back and forth, and the drain portion 31 has a drain portion 31. The second actuating member 62 provided with a second sealing part 52 for opening and closing a) is installed to reciprocate back and forth with the first actuating member 61 to control the discharge of the beverage stored in the beverage container 30.

이를 좀 더 상세하게 설명하면, 먼저 제1작동부재(61)의 전단부(61a)는 설치관(41)의 전면을 관통하여 취출공간(21)으로 일정길이 돌출되도록 연장되고, 후단부(61b)는 결합안내관(43)의 내부까지 연장된다. 결합안내관(43)의 내부에 위치하는 제1작동부재(61)의 후단부(61b)에는 유로(42)를 폐쇄하기 위한 제1밀폐부재(51)가 결합설치되고, 제1밀폐부재(51)의 전면에 대응하는 결합안내관(43)의 내부에 형성된 유로(42)의 직경은 축소되어 제1밀폐부재(51)에 의하여 유로(42)가 폐쇄되도록 하며 제1밀폐부재(51)의 후방에 위치하는 유로(42)는 확관되어 제1밀폐부재(51)가 후측으로 이동할 수 있도록 한다. 이때 제1작동부재(61)는 판의 양측에 봉이 설치된 형태를 취하여 유로(42)를 막지않도록 하며, 봉형상으로 이루어진 전방부에 대향하는 유로(42)는 축소되고, 축소부위의 후방에 대향하는 제1작동부재(61)에는 제3밀폐부재(53)가 설치되어 유로(42)를 폐쇄시킨다. 한편 제1작동부재(61)의 후방 봉상으로 이루어진 부위에는 스프링(64)이 설치되어 제1작동부재(61)를 전방측으로 탄성바이어스하며, 스프링(64)의 전후단은 제1작동부재(61)에 마련된 리브(63)와 결합안내관(43)에 의하여 지지된다.To explain this in more detail, first, the front end portion 61a of the first operating member 61 extends to protrude a predetermined length through the front of the installation pipe 41 to the ejection space 21, and the rear end portion 61b. ) Extends to the inside of the coupling guide tube 43. The first sealing member 51 is installed at the rear end portion 61b of the first operating member 61 positioned inside the coupling guide tube 43 to close the flow passage 42, and the first sealing member ( The diameter of the flow path 42 formed inside the coupling guide tube 43 corresponding to the front surface of the 51 is reduced so that the flow path 42 is closed by the first sealing member 51 and the first sealing member 51 is closed. The flow path 42 located at the rear of the pipe is expanded so that the first sealing member 51 can move to the rear side. At this time, the first actuating member 61 has a shape in which rods are installed at both sides of the plate so as not to block the flow passage 42, and the flow passage 42 facing the front portion formed in the rod shape is reduced and opposed to the rear portion of the reduced portion. A third sealing member 53 is installed in the first operating member 61 to close the flow passage 42. On the other hand, a spring 64 is installed at a portion formed of the rear rod of the first operating member 61 to elastically bias the first operating member 61 to the front side, and the front and rear ends of the spring 64 are the first operating member 61. It is supported by the rib 63 and the coupling guide tube 43 provided in the).

그리고 제2작동부재(62)는 봉상으로 형성되어 그 전단(62a)이 제1작동부재(61)의 후단(61b)에 접하도록 배수부(31)의 내부에 삽입설치된다. 제2작동부재(62)의 후단(62b)은 배수부(31)를 통과하여 음료통(30)의 내부까지 연장형성되고, 배수부(31)의 후측에 위치하는 제2작동부재(62)에는 배수부(31)의 후측면에 밀착되는 제2밀폐부재(52)가 설치되어 배수부(31)를 폐쇄시킨다. 이때 배수부(31)에는 제2작동부재(62)가 전후왕복운동하도록 지지하는 리브(65)가 설치되고, 이 리브(65)와 제2작동부재(62)의 전단(62a)에 형성된 리브(66)사이에는 스프링(67)이 설치되어 제2작동부재(62)를 전방측으로 탄성바이어스한다.In addition, the second operating member 62 is formed in a rod shape, and the front end 62a is inserted into the drainage portion 31 so as to contact the rear end 61b of the first operating member 61. The rear end 62b of the second actuating member 62 extends through the drain portion 31 to the inside of the beverage container 30 and is located at the rear side of the drain portion 31. The second sealing member 52 in close contact with the rear side of the drain 31 is provided to close the drain 31. At this time, the drain portion 31 is provided with a rib 65 for supporting the second operation member 62 to move back and forth, ribs formed on the front end (62a) of the rib 65 and the second operation member 62. A spring 67 is provided between the 66 to elastically bias the second operating member 62 to the front side.

한편 취출공간(21)에는 그 상측이 도어(20)의 외측면에 전후 회동가능하도록 결합된 레버(70)가 그 일면이 설치관(41)의 전방으로 돌출된 제1작동부재(61)의 전단(61a)에 밀착되도록 설치되어 제1작동부재(61)를 용이하게 후방으로 밀도록 한다.Meanwhile, in the ejection space 21, a lever 70 having an upper side coupled to the outer side of the door 20 so as to be rotatable back and forth has one surface of the first operating member 61 protruding forward of the installation pipe 41. It is installed to be in close contact with the front end (61a) to easily push the first operating member 61 to the rear.

그리고 결합안내관(43)에 삽입되는 배수부(31)의 외곽에는 음료의 누수를 방지하기 위한 링형 가스킷(81)이 설치된다.And the outer portion of the drain 31 is inserted into the coupling guide tube 43 is provided with a ring-shaped gasket 81 for preventing the leakage of the beverage.

이와 같이 구성된 본 발명에 따른 냉장고의 음료공급장치의 작동과 그에 따른 효과를 설명하면 다음과 같다.Referring to the operation and the effects thereof of the beverage supply device of the refrigerator according to the present invention configured as described above are as follows.

먼저 배수부가 닫혀 음료가 배출되지 않을때을 제4도의 a를 참조하여 설명한다. 제1작동부재와 제2작동부재는 스프링에 의하여 탄성바이어스되어 전방측으로 이동된 상태여서 배수부는 제2밀폐부재에 의하여 폐쇄되고, 유로는 제1밀폐부재와 제2밀폐부재에 의하여 폐쇄된 상태이다. 이때 제1밀폐부재와 제2밀폐부재는 음료의 배출을 억제하고 제3밀폐부재는 외부공기가 내부로 유입되는 것을 방지한다.First, it will be described with reference to a of FIG. 4 when the drainage portion is closed and no beverage is discharged. The first actuating member and the second actuating member are elastically biased by a spring and moved to the front side, so that the drain portion is closed by the second sealing member, and the flow path is closed by the first sealing member and the second sealing member. . At this time, the first sealing member and the second sealing member to suppress the discharge of the beverage and the third sealing member to prevent the outside air from flowing into.

이 상태에서 레버를 후방측으로 밀면, 제4도의 b에 도시한 바와 같이, 레버에 밀착되어 있던 제1작동부재가 스프링의 탄성력으로 이기고 후방으로 이동함과 동시에 제1작동부재에 접하는 제2작동부재도 후방측으로 이동한다. 이로써 제1밀폐부재와 제3밀폐부재가 제1작동부재를 따라서 후방으로 이동하여 유로를 개방하고, 제2작동부재가 후방으로 이동하여 배수구를 개방시킨다. 이런 과정에 의하여 개방된 배수부와 유로를 통하여 음료통에 저장된 음료가 취출공간으로 배출되는 것이다.When the lever is pushed to the rear side in this state, as shown in b of FIG. 4, the second actuating member which contacts the first actuating member while moving backwards with the elastic force of the spring wins with the elastic force of the spring. Also moves to the rear side. As a result, the first sealing member and the third sealing member move backward along the first operating member to open the flow path, and the second operating member moves backward to open the drain hole. Through this process, the beverage stored in the beverage container is discharged to the discharge space through the open drainage part and the flow path.

음료의 배출을 종료하고자 밀고 있던 레버를 놓으면 제1작동부재와 제2작동부재는 스프링의 탄성력에 의하여 복귀된다. 이로써 제2밀폐부재가 배수부에 밀착되어 배수부를 폐쇄하고, 제1밀폐부재가 유로를 폐쇄하여 음료의 배출을 중지시킨다.When the lever pushed to end the discharging of the beverage is released, the first actuating member and the second actuating member are returned by the spring force. As a result, the second sealing member is in close contact with the drainage portion to close the drainage portion, and the first sealing member closes the flow path to stop the discharge of the beverage.

이상에서 상세하게 설명한 바와 같이, 본 발명에 따른 냉장고의 음료공급장치는 음료의 배출을 조절하는 구조를 단순화시킴으로써 그 청소가 용이해져 양호한 위생상태를 유지시킬 수 있는 이점이 있다. 또한 그 제조와 설치를 쉽게 할 수 있는 이점이 있다.As described in detail above, the beverage supply apparatus of the refrigerator according to the present invention has the advantage of being easy to clean and maintain a good hygiene state by simplifying the structure for controlling the discharge of the beverage. It also has the advantage of easy manufacturing and installation.

그리고 음료통을 저장실에 수납시키기 때문에 음료통의 용량을 원하는 만큼 크게 구성할 수 있는 이점이 있다.And since the beverage container is stored in the storage compartment, there is an advantage that the capacity of the beverage container can be configured as large as desired.

Claims

The refrigerator 10 includes a main body 10 having a refrigerating compartment 11, a door 20 opening and closing the refrigerating compartment 11 of the main body 10, and a take-out space 21 formed in the outer surface of the door 20. In the beverage supply device of the beverage storage 30 so that the beverage is supplied to the take-out space 21 and the beverage container 30 is installed on the top of the refrigerating chamber 11 to be withdrawn via the support plate 13, and the The beverage stored in the beverage container 30 is formed of a hollow body formed with a flow path 42 so that the beverage is discharged into the dispensing space 21. The installation pipe 41 is exposed and installed in the door 20 and the insertion pipe 41 is inserted and installed to reciprocate in the interior of the installation pipe 41 to open and close the flow path 42 to open and close the first sealing member 51 and the third. The first operating member 61 with a sealing member 53 and the beverage container 30 facing the first operating member 61. And a second sealing member 52 provided at the end thereof so as to reciprocate in the drainage portion 31 so as to control the discharge of the beverage to the drainage portion 31 and the drainage portion 31 installed at the front surface of the drainage portion 31. Beverage supply device of the refrigerator, characterized in that consisting of two operating members (62).

2. The beverage supply apparatus of claim 1, wherein the first operating member (61) and the second operating member (62) are elastically restored by the elastic force of the springs (64).

The beverage supply apparatus according to claim 1, wherein a rib (65) is formed in the drain part (31) to support a reciprocating motion of the second operation member (62).

According to claim 1, At the end of the first operating member 61, the first operating member 61 is moved inward of the door 20 so that the beverage of the beverage container 20 is the take-out space Beverage supply apparatus of the refrigerator, characterized in that the upper portion of the lever 70 is rotatably coupled to the take-out space 21 to be supplied to the 21.

The beverage supply of the refrigerator according to claim 1, wherein the drainage part 31 is provided with a coupling guide tube 43 which is coupled to an end of the installation tube 41 when the door 20 is closed. Device.

6. The beverage supply apparatus of the refrigerator according to claim 5, wherein a gasket (81) is provided at a coupling portion of the coupling guide tube (43) and the drainage portion (31) to prevent leakage of the beverage.

According to claim 1, wherein the end of the flow path 42 of the installation pipe 41, the beverage supply apparatus of the refrigerator, characterized in that the convexly formed in the downward direction so that the beverage is supplied to the discharge space (21).