Patent Publication Number: US-2020289997-A1

Title: Outpouring assembly

Description:
FIELD OF TECHNOLOGY 
     The present invention belongs to the coating color mixing field, and specifically, to a backflow outpouring assembly. 
     BACKGROUND 
     A color mixer is a commonly used device in the coating field, and is used to take and mix different coatings according to a requirement to obtain a required coating, such as emulsion paint. There are multiple assemblies in the color mixer for outpouring a color paste. The outpouring assemblies include a color paste bucket, a pump body, and the like, and outpour a color paste through a paste discharge channel or a paste discharge nozzle. The outpouring assemblies are arranged on the color mixer in a plurality of manners. Generally, the plurality of outpouring assemblies are arranged in a straight line or in a circle. Paste discharge nozzles of the outpouring assemblies arranged in a circle may be concentrated in one range, and are suitable for an automatic color mixing mechanism that simultaneously outpours at least two color pastes. There are also many types of outpouring assemblies, including a backflow outpouring assembly with a drying prevention function and the like. The patent CN105026307B of ALLOCATION VALVE ASSEMBLY AND COLOR PASTE ALLOCATION APPARATUS FOR COLOR MIXER provides a backflow outpouring assembly and a color paste allocation apparatus. However, some problems still exist. Because of tension of a liquid such as a color paste, the liquid is easily adsorbed at a paste outlet of a paste discharge channel of the outpouring assembly, thereby reducing outpouring precision of the color paste. A residual color paste needs to be cleaned up after the color paste is outpoured. An existing outpouring assembly and a structure of a cleaning mechanism cause insufficient cleaning. 
     SUMMARY 
     The present invention provides a backflow outpouring assembly that facilitates cleaning of a residual color paste and an increase in precision. 
     An outpouring assembly, comprising an outpouring plate, wherein the outpouring plate is provided with a liquid outlet through hole, a paste discharge pipe is disposed in the liquid outlet through hole, the paste discharge pipe moves up and down in the liquid outlet through hole, and when a lower end of the paste discharge pipe extends out of the liquid outlet through hole, the paste discharge pipe is in a liquid outpouring state. 
     A thickness of a wall of a lower end surface of the paste discharge pipe is less than 1 millimeter; or the paste discharge pipe is a thin-wall pipe, and a thickness of the thin-wall pipe is less than 1 millimeter; or a thickness of a wall of a lower end of the paste discharge pipe gradually decreases from top to bottom. 
     The paste discharge pipe moves up and down in the liquid outlet through hole means that the paste discharge pipe is subjected to downward force to extend downwards and is subjected to upward force to retract. 
     An oscillating rod rotatably disposed on the outpouring plate, wherein an upper limiting stopper and a lower limiting stopper are disposed on the paste discharge pipe, and an end A of the oscillating rod is located between the upper limiting stopper and the lower limiting stopper; or a lower limiting stopper is located on the paste discharge pipe, an end A of the oscillating rod is located above the lower limiting stopper, and a spring is disposed between the paste discharge pipe and the outpouring plate. 
     A first valve member, wherein the first valve member comprises at least one backflow channel, and relative movement is performed between the first valve member and the outpouring plate, so that the outpouring assembly performs switching between an outpouring location and a backflow location; and further comprising a mounting bracket, wherein a first linear drive mechanism is disposed on the mounting bracket, and a mobile end of the first linear drive mechanism is fixedly connected to the outpouring plate, to enable the outpouring plate to move; an end B of the oscillating rod is disposed in a horizontal strip-shaped groove of the mounting bracket, and a stroke of horizontal movement of the outpouring plate is greater than a horizontal length of the horizontal strip-shaped groove; a shape of the horizontal strip-shaped groove correspondingly coordinates with an oscillation margin of the oscillating rod. 
     The outpouring assembly is a backflow outpouring assembly, the backflow outpouring assembly further comprises a first valve member, the first valve member comprises at least one backflow channel, and relative movement is performed between the first valve member and the outpouring plate, so that the backflow outpouring assembly performs switching between an outpouring location and a backflow location. 
     A contact surface between the first valve member and the outpouring plate are slope surfaces. 
     Relative movement is performed between the first valve member and the outpouring plate, so that the backflow outpouring assembly performs switching between an outpouring location and a backflow location means that the outpouring plate horizontally moves, and that the first valve member and the outpouring plate coordinately move up and down, so that the two remain in contact through the contact surface. 
     The backflow outpouring assembly further comprises a mounting bracket, a horizontal rail pair is disposed on the mounting bracket, a sliding block of the horizontal rail pair is fixedly connected to a mobile apparatus, the mobile apparatus comprises a mobile bracket, and a lead screw mechanism is disposed on the mobile bracket; the lead screw mechanism comprises a screw and a nut; the screw is rotatably disposed on the mobile bracket, and in a moving direction of the mobile bracket, the contact surface between the outpouring plate and the first valve member is parallel to an axis of the screw; the nut is disposed in a limiting groove of the mounting bracket in a manner of sliding up and down; the limiting groove limits horizontal movement of the nut; the nut is fixedly connected to the first valve member. 
     A lower portion of the first valve member is elastically connected to a compression sliding block, and the compression sliding block and a second rail on the mobile bracket constitute a second rail pair; an axis of the second rail is parallel to the axis of the screw. 
     A location sensor or a stroke switch for determining a moving distance of the outpouring plate is disposed between the outpouring plate and the first valve member. 
     A paste discharge pipe is disposed in the liquid outlet through hole, the paste discharge pipe moves up and down in the liquid outlet through hole, and when a lower end of the paste discharge pipe extends out of the through hole, the paste discharge pipe is in a liquid outpouring state; that the paste discharge pipe moves up and down in the liquid outlet through hole means that the paste discharge pipe is subjected to downward force to extend downwards and is subjected to upward force to retract. 
     A paste discharge pipe is disposed in the liquid outlet through hole, the paste discharge pipe moves up and down in the liquid outlet through hole, and when a lower end of the paste discharge pipe extends out of the through hole, the paste discharge pipe is in a liquid outpouring state; that the paste discharge pipe moves up and down in the liquid outlet through hole means that the paste discharge pipe is subjected to downward force to extend downwards and is subjected to upward force to retract. 
     An oscillating rod rotatably disposed on the outpouring plate, wherein an upper limiting stopper and a lower limiting stopper are disposed on the paste discharge pipe, and an end A of the oscillating rod is located between the upper limiting stopper and the lower limiting stopper; an end B of the oscillating rod is disposed in a horizontal strip-shaped groove of the mounting bracket, and a stroke of horizontal movement of the outpouring plate is greater than a horizontal length of the horizontal strip-shaped groove; a shape of the horizontal strip-shaped groove correspondingly coordinates with an oscillation margin of the oscillating rod. 
     An oscillating rod rotatably disposed on the outpouring plate, wherein a lower limiting stopper is disposed on the paste discharge pipe, an end A of the oscillating rod is located above the lower limiting stopper, and a spring is disposed between the paste discharge pipe and the outpouring plate; an end B of the oscillating rod is disposed in a horizontal strip-shaped groove of the mounting bracket, and a stroke of horizontal movement of the outpouring plate is greater than a horizontal length of the horizontal strip-shaped groove; a shape of the horizontal strip-shaped groove correspondingly coordinates with an oscillation margin of the oscillating rod. 
     A sealing mechanism is disposed between the liquid outlet through hole and the paste discharge pipe. 
     A beneficial effect of the present invention is as follows: A contact surface between a first valve member and an outpouring plate is a plane, in other words, an axis or a length direction of a liquid outlet through hole is perpendicular to the contact surface. In such a structure, it is inconvenient to clean a residual color paste after a color paste is outpoured. In the present invention, the contact surface between the first valve member and the outpouring plate is set to a slope plane. There is an included angle between the axis or the length direction of the liquid outlet through hole and the contact surface. In such a structure, it is easier for the residual color paste to gather downwards at a cleaning location, facilitating cleaning by a cleaning tool. 
     Because a liquid such as the color paste or water has surface tension, the color paste adheres to a surface of an outlet. The outpouring plate is in a planar state in most cases, and when the color paste is directly outpoured from the liquid outlet through hole, relatively many color pastes adhere to the outlet of the liquid outlet through hole, thereby affecting a quantity of outpoured color pastes. In this case, outpouring precision of the outpouring assembly is affected. A paste discharge pipe is disposed in the liquid outlet through hole, so that a quantity of color pastes adhered to a paste discharge outlet of the paste discharge pipe can be effectively reduced. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic diagram of distribution of outpouring assemblies in a color mixer and a cleaning mechanism; 
         FIG. 2  is a diagram of circumferential distribution of outpouring assemblies in a color mixer; 
         FIG. 3  is a schematic diagram of a backflow outpouring assembly; 
         FIG. 4  is a schematic diagram of an outpouring plate; 
         FIG. 5  is a section view of  FIG. 4 ; 
         FIG. 6  is a schematic diagram of a cleaning mechanism; 
         FIG. 7  is a schematic diagram of an elevating mechanism in an extended state; 
         FIG. 8  is a section view of  FIG. 3 ; and 
         FIG. 9  is a schematic diagram of a first valve member, where  1  indicates a rack,  11  indicates a base,  12  indicates outlet space,  2  indicates a backflow outpouring assembly,  20  indicates an outpouring plate,  200  indicates a backflow through hole,  201  indicates a liquid outlet through hole,  21  indicates a backflow pipe,  22  indicates a paste discharge pipe,  220  indicates an upper limiting stopper,  221  indicates a lower limiting stopper,  23  indicates a sealing mechanism,  24  indicates an oscillating rod,  25  indicates a spring,  26  indicates a first valve member,  260  indicates a backflow channel,  27  indicates a cleaning groove,  3  indicates a mounting bracket,  30  indicates a horizontal strip-shaped groove,  31  indicates a limiting groove,  4  indicates a horizontal rail pair,  40  indicates a sliding block,  5  indicates a mobile bracket,  50  indicates a screw,  51  indicates a nut,  52  indicates a first motor,  53  indicates a second rail,  54  indicates a sensor,  6  indicates a compression sliding block,  60  indicates a guiding column,  61  indicates a compression spring,  7  indicates a cleaning mechanism,  70  indicates a brush,  71  indicates a mounting plate,  72  indicates an upper support arm,  73  indicates a lower mounting plate,  74  indicates a lower support arm,  75  indicates a second lead screw mechanism,  76  indicates a linear telescopic mechanism,  77  indicates an engaged tooth, and  78  indicates a plurality of sections of sleeves. 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     As shown in  FIG. 1  to  FIG. 9 , an outpouring assembly is provided, including an outpouring plate  20 . The outpouring plate  20  is provided with a liquid outlet through hole  201 , a paste discharge pipe  22  is disposed in the liquid outlet through hole  201 , the paste discharge pipe  22  moves up and down in the liquid outlet through hole  201 , and when a lower end of the paste discharge pipe  22  extends out of the liquid outlet through hole  201 , the paste discharge pipe  22  is in a liquid outpouring state. The paste discharge pipe  22  herein communicates with a color paste pump by using a pump body. Because a liquid such as the color paste or water has surface tension, the color paste adheres to a surface of an outlet. The outpouring plate  20  is in a planar state in most cases, and when the color paste is directly outpoured from the liquid outlet through hole  201 , relatively many color pastes adhere to the outlet of the liquid outlet through hole  201 , thereby affecting a quantity of outpoured color pastes. In this case, outpouring precision of the outpouring assembly is affected. The paste discharge pipe  22  is disposed in the liquid outlet through hole  201 , so that a quantity of color pastes adhered to the paste discharge outlet of the paste discharge pipe can be effectively reduced. 
     A thickness of a wall of a lower end surface of the paste discharge pipe  22  is less than 1 millimeter. With a same inner diameter of paste discharge outlets of the paste discharge pipe  22 , a smaller wall thickness leads to higher precision. The thickness of the wall may be preferably 0.5 millimeter or lower. Alternatively, the paste discharge pipe  22  is a thin-wall pipe, and the thickness of the thin-wall pipe is less than 1 millimeter. Alternatively, the thickness of the wall at a lower end of the paste discharge pipe  22  gradually decreases from top to bottom. The thickness of the end surface, in other words, the thickness of the wall at the paste discharge outlet, is less than 1 millimeter. A sealing mechanism  23  is disposed between the liquid outlet through hole  201  and the paste discharge pipe  22 . A sealing ring may be selected as the sealing mechanism  23 . 
     That the paste discharge pipe  22  moves up and down in the liquid outlet through hole  201  means that the paste discharge pipe  22  is subjected to downward force to extend downwards and is subjected to upward force to retract. A specific structure may be as follows: The outpouring assembly further includes an oscillating rod  24  rotatably disposed on the outpouring plate  20 . An upper limiting stopper  220  and a lower limiting stopper  221  are disposed on the paste discharge pipe  22 , and an end A of the oscillating rod  24  is located between the upper limiting stopper  20  and the lower limiting stopper  221 . When the end A of the oscillating rod  24  rotates downwards, the end A of the oscillating rod  24  pushes the lower limiting stopper  221  and the paste discharge pipe  22  to move downwards together. When the oscillating rod  24  rotates upwards, the end A of the oscillating rod  24  pushes the upper limiting stopper  220  and the paste discharge pipe  22  to move upwards together. A power source needs to be provided to the oscillating rod  24  to enable the oscillating rod to rotate. A common mechanism may be used as a power source for oscillation. The oscillating rod  24  may be set to a shape of “7” or another shape according to an actual case. The upper limiting stopper  220  and the lower limiting stopper  221  are located above the outpouring plate  20 , in other words, on a side far away from a contact surface between the outpouring plate  20  and the first valve member  26 . 
     Alternatively, the outpouring assembly further includes an oscillating rod  24  rotatably disposed on the outpouring plate  20 . The paste discharge pipe  22  is located above the outpouring plate  20 , a lower limiting stopper  221  is disposed above the paste discharge pipe  22 , an end A of the oscillating rod is located above the lower limiting stopper  221 , and a spring  25  is disposed between the paste discharge pipe and the outpouring plate  20 . When the end A of the oscillating rod  24  rotates downwards, the end A of the oscillating rod pushes the lower limiting stopper  221  and the paste discharge pipe  22  to move downwards together. When the end A of the oscillating rod  24  rotates upwards, resilience force of the spring  25  provides the paste discharge pipe with upward force. The spring  25  may also be added to the previous embodiment. However, the spring  25  in the previous embodiment makes a cushioning effect. 
     To prevent a color paste from drying in a channel or at an outpouring outlet, an outpouring assembly having a backflow function may be used, in other words, a backflow outpouring assembly  2 . The backflow outpouring assembly  2  further includes a first valve member  26 , the first valve member  26  includes at least one backflow channel  260 , and relative movement is performed between the first valve member  26  and the outpouring plate  20 , so that the backflow outpouring assembly  2  performs switching between an outpouring location and a backflow location. The contact surface between the first valve member  26  and the outpouring plate  20  is preferably a plane. A backflow through hole  200  is further provided on the outpouring plate  20 , and a backflow pipe  21  is disposed in the backflow through hole  200 . At the backflow location, the liquid outlet through hole  201 , the backflow channel  260 , the backflow through hole  200  communicate with each other. Certainly, there are other backflow manners and other required structures, as shown in the patent CN105026307B. These are existing technologies, and are not described in detail again. 
     The outpouring assembly may further include a mounting bracket  3 . A first linear drive mechanism is disposed on the mounting bracket  3 , and a mobile end of the first linear drive mechanism is fixedly connected to the outpouring plate  20 , to enable the outpouring plate  20  to move. An end B of the oscillating rod  24  is disposed in a horizontal strip-shaped groove  30  of the mounting bracket  3 , and a stroke of horizontal movement of the outpouring plate  20  is greater than a horizontal length of the horizontal strip-shaped groove  30 . A shape of the horizontal strip-shaped groove  30  correspondingly coordinates with an oscillation margin of the oscillating rod  24 . 
     In addition, the existing backflow outpouring assembly  2  includes the first valve member  26  and the outpouring plate  20 . The outpouring plate  20  includes at least one liquid outlet through hole  201 , the first valve member  26  includes at least one backflow channel  260 , and relative movement is performed between the first valve member  26  and the outpouring plate, so that the backflow outpouring assembly performs switching between an outpouring location and a backflow location. A contact surface between the first valve member  26  and an outpouring plate  20  is a plane, in other words, an axis or a length direction of the liquid outlet through hole  201  is perpendicular to the contact surface. In such a structure, it is inconvenient to clean a residual color paste after a color paste is outpoured. In the present invention, the contact surface between the first valve member  26  and the outpouring plate  20  may be set to a slope plane. There is an included angle between the axis or the length direction of the liquid outlet through hole  201  and the contact surface. In such a structure, it is easier for the residual color paste to gather downwards at a cleaning location, facilitating cleaning by a cleaning tool. 
     That relative movement is performed between the first valve member  26  and the outpouring plate  20 , so that the backflow outpouring assembly  2  performs switching between an outpouring location and a backflow location means that the outpouring plate  20  horizontally moves, and that the first valve member  26  and the outpouring plate  20  coordinately move up and down, so that the two remain in contact through the contact surface. The outpouring plate  20  and the first valve member  26  are slope. When the outpouring plate  20  horizontally moves, the first valve member  26  needs to move up and down to ensure that the outpouring plate  20  is always in contact with the first valve member  26 . 
     The backflow outpouring assembly  2  further includes a mounting bracket  3 , a horizontal rail pair  4  is disposed on the mounting bracket  3 , a sliding block  40  of the horizontal rail pair is fixedly connected to a mobile apparatus, the mobile apparatus includes a mobile bracket  5 , and a lead screw mechanism is disposed on the mobile bracket  5 . The lead screw mechanism includes a screw  50  and a nut  51 . The screw  50  is rotatably disposed on the mobile bracket  5 , and in a moving direction of the mobile bracket, the contact surface between the outpouring plate  20  and the first valve member  26  is parallel to an axis of the screw  50 . The nut  51  is disposed in a limiting groove  31  of the mounting bracket  3  in a manner of sliding up and down. The limiting groove  31  limits horizontal movement of the nut  51 . The nut  51  is fixedly connected to the first valve member  26 . The screw  50  of the lead screw mechanism is rotatably disposed on the mobile bracket  5  by using a bearing. The screw  50  is driven by a first motor  52  for rotation. The first motor  52  may be a servo motor. The limiting groove  31  is perpendicular to a moving direction of the mobile bracket  5 , and the nut  51  linearly moves in the limiting groove  31 . A line of intersection, with the contact surface between the outpouring plate  20  and the first valve member  26 , of a plane in which the axis of the screw  50  and the moving direction of the mobile bracket  5  are located is parallel to the axis of the screw  50 . The screw  50  is slope, and the sliding block  40  fixed on the screw  50  can linearly move only in a horizontal direction. Therefore, the screw  50  moves horizontally and linearly while rotating, to drive the outpouring plate  20  to move, and the nut  51  moves up and down to drive the first valve member  26  to move. 
     A lower portion of the first valve member  26  is elastically connected to a compression sliding block  6 , and the compression sliding block  6  and a second rail  53  on the mobile bracket  5  constitute a second rail pair. An axis of the second rail  53  is parallel to the axis of the screw  50 . The first valve member  26  and the compression sliding block  6  are provided with a guiding hole, a removable guiding column  60  is disposed in the guiding hole, and a compression spring  61  is disposed out of the guiding column  60  located between the first valve member  26  and the compression sliding block  6 . A rolling wheel is rotatably disposed below the compression sliding block  6 , and the rolling wheel slides in a guiding groove of the second rail  53 , so that the compression sliding block  6  rolls on the second rail  53 . The rolling wheel herein may directly use a bearing. The compression sliding block may enable elastic compression to be performed between the first valve member  26  and the outpouring plate  20 . 
     A location sensor  54  or a stroke switch for determining a moving distance of the outpouring plate is disposed between the outpouring plate  20  and the first valve member  26 . For example, transmit ends or receive ends of two location sensors are disposed on the mobile bracket  5  along a straight line parallel to the axis of the screw  50 , and a tail end of the first valve member  26  is connected to the other end of the location sensor  54 , so as to determine a relative moving distance between the outpouring plate  20  and the first valve member  26 . 
     In addition, the paste discharge pipe  22  moving up and down in the liquid outlet through hole  201  may also be disposed in the liquid outlet through hole  201  of the backflow outpouring assembly  2 , as shown in the structure in the embodiment of the outpouring assembly in this application. In other words, when a lower end of the paste discharge pipe  22  extends out of the liquid outlet through hole  201 , the paste discharge pipe  22  is in a liquid outpouring state. That the paste discharge pipe  22  moves up and down in the liquid outlet through hole  201  means that the paste discharge pipe  22  is subjected to downward force to extend downwards and is subjected to upward force to retract. 
     The backflow outpouring assembly  2  further includes an oscillating rod rotatably disposed on the outpouring plate  20 . An upper limiting stopper  220  and a lower limiting stopper  221  are disposed on the paste discharge pipe  22 , and an end A of the oscillating rod is located between the upper limiting stopper  220  and the lower limiting stopper  221 . Alternatively, only a lower limiting stopper  221  needs to be located on the paste discharge pipe  22 , an end A of the oscillating rod  24  is located above the lower limiting stopper  221 , and a spring  25  is disposed between the paste discharge pipe  22  and the outpouring plate  20 . The end A of the oscillating rod  24  is restored upwards by elastic force of the spring  25 . In the two structures, an end B of the oscillating rod  24  is disposed in the horizontal strip-shaped groove  30  of the mounting bracket  3 , and a stroke of horizontal movement of the outpouring plate  20  is greater than a horizontal length of the horizontal strip-shaped groove  30 . A shape of the horizontal strip-shaped groove  30  correspondingly coordinates with an oscillation margin of the oscillating rod  24 . Assuming that the outpouring plate  20  moves forward, a liquid discharge channel is opened. In a process in which the outpouring plate  20  moves forward and the first valve member  26  moves upwards, the oscillating rod  24  horizontally moves with the outpouring plate  20 . When moving to a foremost end of the horizontal strip-shaped groove  30 , the end B of the oscillating rod  24  is clamped by the horizontal strip-shaped groove  30 , a part that is of the oscillating rod  24  and that is rotatably connected to the outpouring plate  20  continues moving forward, the end B of the oscillating rod  24  oscillates upwards, and the end A of the oscillating rod  24  oscillates downwards. Certainly, a sealing mechanism is also disposed between the liquid outlet through hole  201  and the paste discharge pipe  22 . 
     The foregoing backflow outpouring assembly  2  may be applied to various color mixers, and is preferably applied to an automatic color mixer that can also perform outpouring. Such an automatic color mixer includes a rack  1 , and a color paste allocation unit is disposed on the rack  1 . The color paste allocation unit includes a color paste bucket storing a color paste, a pump body communicating with a liquid in the color paste bucket, and the backflow outpouring assembly  2 . An outpouring channel of the backflow outpouring assembly  2  is connected to the pump body, and a backflow channel is connected to the color paste bucket. A base  11  is disposed on the color mixer, outlet space  12  for cleaning, paste receiving, and allocation is disposed on the base  11 , and a plurality of backflow outpouring assemblies  2  are circumferentially distributed on the base  11  of the color mixer along the outlet space  12 . A cleaning groove is disposed on side surfaces of front ends of the outpouring plate  20  and the first valve member  26 . A residual color paste enters the cleaning groove  27 , and is cleaned by using the cleaning mechanism. The side surface of the front end herein is a side surface of a section close to the outlet space  12 . A front end of the horizontal strip-shaped groove  30  also points to one end of the outlet space  12 . For other functions of the color mixer, refer to the patent CN105026307B. The backflow outpouring assemblies  2  of such a color mixer are intensively distributed along the outlet space  12 . A paint mixing cup for receiving a color paste may be disposed under the outlet space  12 . When one or more color pastes are required, the color pastes may be simultaneously outpoured by using the pump body and the paste discharge pipe. The color paste allocation unit may further include several valve bodies, so as to control a quantity of color pastes outpoured through each paste discharge pipe. Each color paste allocation unit may perform outpouring in large quantities, or may perform outpouring in small quantities, or may perform back flowing. Herein, the contact surface between the first valve member  26  and the outpouring plate  20  in the backflow outpouring assembly may be slope or horizontal. 
     The color mixer requires a dedicated cleaning mechanism  7 . A horizontal moving mechanism is disposed on a body of the color mixer, an elevating mechanism is disposed on the horizontal moving mechanism, and a brush  70  rotating around an axis of the brush  70  is disposed on the elevating mechanism. The horizontal moving mechanism may be a common linear mechanism. A second lead screw mechanism  75  driven by a second motor is disposed on the rack  1  of the color mixer, and the elevating mechanism slides on a second screw of the second lead screw mechanism  75 . The brush  70  may be a cylindrical brush  70 . During cleaning, the brush enters the outlet space  12 , and rotates to clean residual color pastes on the side surfaces of the front ends of the first valve member  26  and the outpouring plate  20 . 
     The elevating mechanism includes a mounting plate  71  disposed on the rack. The mounting plate  71  is rotatably connected to two upper support arms  72 . An end that is of each of the two upper support arms  72  and that is far away from the mounting plate  71  is connected to one lower support arm  74 . Two lower support arms  74  are rotatably connected to a lower mounting plate  73 . The lower mounting plate  73  is rotatably connected to the brush  70 . A linear telescopic mechanism  76  is disposed between the two upper support arms  72  or the two lower support arms  74 , and the linear telescopic mechanism  76  telescopes to drive the lower mounting plate  73  to move up and down. Preferably, the two upper support arms  72  have an equal length, the two lower support arms  74  have an equal length, or the upper support arm  72  and the lower support arm  74  have an equal length, so as to ensure that the brush  70  performs linear motion. The upper support arm  72  is hingedly connected to the mounting plate  71 , the lower support arm  74  is hingedly connected to the lower mounting plate  73 , and the upper and lower support arms are hingedly connected. The two upper support arms  72  are symmetrically disposed. The linear telescopic mechanism may be an air cylinder mechanism, a lead screw mechanism, or the like. The linear telescopic mechanism  76  is rotatably connected to or hingedly connected to the upper support arm  72  or the lower support arm  74 . 
     That the upper support arm  72  and the lower support arm  74  are hingedly connected is that a lower end of the upper support arm  72  and an upper end of the lower support arm  74  are rotatably disposed on a hinged shaft. Two hinged shafts are respectively connected to a telescoping end and a fixing end of the linear telescopic mechanism  76 . 
     Circumferentially distributed engaged teeth  77  centering on a rotating shaft rotating around the mounting plate  71  of the upper support arm  72  is disposed at an end of two upper support arms  72  that is located on the mounting plate  71 , and the engaged teeth  77  of the two upper support arms  72  are mutually engaged and clamped. 
     Circumferentially distributed engaged teeth  77  centering on a rotating shaft rotating around the mounting plate  73  of the lower support arm  74  is disposed at an end of two lower support arms  74  that is located on the mounting plate  73 , and the engaged teeth  77  of the two lower support arms  74  are mutually engaged. 
     A plurality of sections of telescopic sleeves  78  are rotatably disposed on the mounting plate  71 , and the plurality of sections of the sleeves are driven by a drive mechanism to rotate. The plurality of sections of the sleeves include at least two sections of sleeves, adjacent sleeves are slidably connected, and the sleeve herein may be a hollow rod body or of another proper shape. A brush  70  is fixed at a tail end of the plurality of sections of the sleeves. A third motor is disposed on the mounting plate  71 , and the third motor drives, by using the drive mechanism, a first section of the sleeves to rotate. No relative movement but only relative rotation occurs between the first section of the sleeves and the mounting plate  71 . A second section of the sleeves is slidably disposed in the first section of the sleeves, a third section of the sleeves is slidably disposed in the second section of the sleeves, and the plurality of sections of the sleeves are sequentially disposed. A first sliding groove is disposed on the first section of the sleeves, a first sliding block is disposed at an upper end of the second section of the sleeves, and the first sliding block slides in the first groove. A second sliding groove is disposed on the second section of the sleeves, a second sliding block is disposed on the second section of the sleeves, and the second sliding block slides in the second groove. The final section of the sleeves, in other words, the tail end of the plurality of sections of the sleeves  78 , is rotatably connected to the lower mounting plate by using a bearing. The final section of the sleeves is located under the lower mounting plate  73 , and is provided with a fixing sleeve that prevents the lower mounting plate  73  from sliding on the sleeves. The brush  70  is fixedly disposed at the tail end of the plurality of sections of the sleeves. Alternatively, the brush  70  is rotatably disposed on the lower mounting plate  73  by using a rotating shaft, and the plurality of sections of the sleeves are fixedly connected to the rotating shaft of the brush  70 . Another disposing manner may be used, as long as the brush  70  both can linearly move with the lower mounting plate and can rotate with the plurality of sections of the sleeves  78 . The cleaning mechanism in this application may be applied to other types of color mixers, as long as the cleaning mechanism can be used for cleaning a color paste, not necessary the color mixer that simultaneously performs outpouring. 
     During specific implementation, where one or more color pastes are required, a control system controls a corresponding color paste allocation unit to enable a corresponding backflow outpouring assembly  2  to work, to outpour a corresponding quantity of color pastes. First, the first motor is started, the screw  50  rotates, the mobile bracket  5 , the sliding block  40 , the screw  50 , the first motor  52 , the oscillating rod  24 , the outpouring plate  20 , the second rail  53 , and the like moves together to a center of the outlet space, and the nut  51 , the first valve member  26 , and the compression sliding block  6  moves upwards, so that the liquid outlet through hole  201  of the outpouring plate  20  moves out of the first valve member  26 . Motion is continued. The end B of the oscillating rod  24  is blocked after moving to one end that is of the horizontal strip-shaped groove  30  and that is close to the outlet space. The oscillating rod  24  oscillates while moving. The paste discharge pipe  22  extends from the liquid outlet through hole  200  to a predetermined location, in other words, the outpouring location. The pump body of a backflow outpouring mechanism is opened to outpour a color paste. After the outpouring is completed, the first motor  52  moves in a reverse direction, the paste discharge pipe  22  retracts back to the liquid outlet through hole  200 , and the first valve member  26  and the outpouring plate  20  reversely move to the backflow location. In this case, a residual color paste enters the cleaning groove  27 . 
     The cleaning mechanism  7  starts cleaning, the second lead screw mechanism  75  is started, and the elevating mechanism moves until the brush  70  moves to a location above of the outlet space  12 . The linear telescopic mechanism  76  retracts, the two upper support arms  72  and the two lower support arms  74  are separately closed, the lower mounting plate  73  moves downwards to drive the brush  70  to move to space surrounded by the backflow outpouring assemblies  2 , and the third motor drives the brush  70  to rotate to clean the residual color paste on the backflow outpouring assembly  2 . After the cleaning is completed, the elevation mechanism elevates and moves to an initial location. 
     Location relationships between the orientations in the above embodiments: above, under, an upper end, a lower end, horizontal, perpendicular, front, and back are relative location relationships, and do not represent the actual up, down, front, and back locations. 
     The technical features of the foregoing embodiments can be arbitrarily combined. To simplify the descriptions, all possible combinations of the technical features in the above embodiments have not been described. However, as long as there is no contradiction in the combinations of these technical features, it should be considered as the scope described in this specification.