Patent Publication Number: US-2023143875-A1

Title: Distribution wheel and particulate matter releasing apparatus

Description:
CROSS REFERENCE 
     The present application claims the priority of Chinese Patent Application No. 202122739352.7, filed on Nov. 9, 2021, which is entirely incorporated into the present disclosure by reference. 
     TECHNICAL FIELD 
     The present disclosure relates to a technical field of pet supplies, and more particularly to a distribution wheel and a particulate matter releasing apparatus. 
     BACKGROUND 
     More and more people enjoy feeding pets, and pets as friends of humans also greatly improve the quality of people&#39;s life. 
     The pet feeder in the related art generally includes a hopper, a distribution wheel, and an ejection assembly. The distribution wheel includes a circumferential surface which defines a recess. Pet food (which is in a particulate form) accommodated in the hopper may enter the recess when the distribution wheel is rotated to a position where an opening of the recess is upward or diagonally upward. The pet food in the recess drops onto a preset position when the distribution wheel is rotated to another position where the opening of the recess is downward or obliquely downward. And then the ejection assembly ejects the pet food dropped onto the preset position to feed the pet. However, in the related art, there is usually a problem that pet food falls out of the recess of the distribution wheel in advance, and cannot be delivered to the preset position smoothly. 
     SUMMARY 
     The present disclosure provides a distribution wheel and a particulate matter releasing apparatus to solve a problem that pet food falls out of the recess of the distribution wheel in advance, and cannot be delivered to a preset position smoothly. 
     A first technical solution provided by the present disclosure is to provide a particulate matter releasing apparatus. The particulate matter releasing apparatus includes a distribution wheel and a driving member. The distribution wheel includes a circumferential surface and defines a recess on the circumferential surface. The recess is configured for receiving particulate matter. An opening size of the recess is less than a bottom size of the recess. The driving member is configured to drive the distribution wheel to rotate. 
     In the present disclosure, an opening size of the recess may be less than a bottom size of the recess, so as to avoid a situation that the particulate matter in the recess falls out of the opening of the recess prematurely and cannot reach a preset position when the distribution wheel is rotated to a position where the opening of the recess is downward or obliquely downward. 
     A second technical solution provided by the present disclosure is to provide a distribution wheel. The distribution wheel is configured to release particulate matter. The distribution wheel includes a circumferential surface and defines a recess on the circumferential surface. The recess is configured for receiving particulate matter. The recess includes a first side wall and a second side wall disposed oppositely to each other. The first side wall is in front of the second side wall in a rotational direction of the distribution wheel. A top end of the first side wall is located at an intersection of a first reference surface and a second reference surface. The first reference surface is a plane on which an opening of the recess is located. The second reference surface is perpendicular to the first reference surface. A remaining portion of the first side wall other than the top end is located at a side of the second reference surface away from the second side wall. 
     A third technical solution provided by the present disclosure is to provide a particulate matter releasing apparatus. The particulate matter releasing apparatus includes a driving member and a distribution wheel described above. The driving member is configured to drive the distribution wheel to rotate. 
     In the present disclosure, the remaining portion of the first side wall other than the top end is located at a side of the second reference surface away from the second side wall. When the distribution wheel is rotated to a position where the opening of the recess is downward or obliquely downward, the first side wall may retain the particulate matter in the recess to avoid a situation that the particulate matter falls out of the recess along the first side wall prematurely, and cannot reach a preset position. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In order to illustrate the technical solutions in the embodiments of the present disclosure or the prior art more clearly, the following will briefly introduce the figures needed to be used in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present disclosure. Those skilled in the art may derive other figures from these figures without paying any creative work. 
         FIG.  1    is a structural schematic view of an embodiment of a particulate matter releasing apparatus of the present disclosure. 
         FIG.  2    is an exploded structural schematic view of the particulate matter releasing apparatus shown in  FIG.  1   . 
         FIG.  3    is a structural schematic view of a first housing shown in  FIG.  2   ; 
         FIG.  4    is another exploded structural schematic view of the particulate matter releasing apparatus shown in  FIG.  1   . 
         FIG.  5    is a structural schematic view of a distribution wheel shown in  FIG.  2   . 
         FIG.  6    is a cross-sectional structural schematic view of the distribution wheel shown in  FIG.  5    along line A-A. 
         FIG.  7    is the same view as  FIG.  6   . 
         FIG.  8    is the same view as  FIG.  6   . 
         FIG.  9    is the same view as  FIG.  6   . 
         FIG.  10    is the same view as  FIG.  6   . 
         FIG.  11    is the same view as  FIG.  6   . 
         FIG.  12    is an exploded structural schematic view of the distribution wheel shown in  FIG.  5   . 
         FIG.  13    is a schematic structural view of an embodiment of a distribution wheel in the related art. 
     
    
    
     DETAILED DESCRIPTION 
     The technical solutions in the embodiments of the present disclosure will be described clearly and completely with reference to the figures in the embodiments of the present disclosure. Obviously, the described embodiments are only a part of the embodiments of the present disclosure, rather than all the embodiments. Based on the embodiments of the present disclosure, all other embodiments obtained by those skilled in the art without any creative work are within the scope of the present disclosure. 
     Mentioning “embodiments” herein means that a specific feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present disclosure. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments. 
     The terms “first”, “second”, and “third” in the embodiments of the present disclosure are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Thus, the features defined with “first”, “second”, and “third” may explicitly or implicitly include at least one of the features. In the description of the present application, “a plurality of” means at least two, e. g., two, three, etc., unless specifically defined otherwise. All directional indications (such as up, down, left, right, front, back) in the embodiments of the present disclosure are only used to account for relative positional relationships, motion conditions, etc., between components in a particular orientation (as shown in the drawings), if the particular orientation changed, correspondingly changes the directional indications. In addition, the terms “including” and “having” and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes unlisted steps or units, or optionally also includes other steps or units inherent to these processes, methods, products or equipment. 
     Please refer to  FIG.  1    and  FIG.  2   .  FIG.  1    is a structural schematic view of an embodiment of a particulate matter releasing apparatus of the present disclosure.  FIG.  2    is an exploded structural schematic view of the particulate matter releasing apparatus shown in  FIG.  1   . The present disclosure provides a particulate matter releasing apparatus  100 . The particulate matter releasing apparatus  100  includes an outer housing (which is not shown in the figures), an inner housing  10  disposed within the outer housing, a distribution wheel  20  disposed within the inner housing  10 , a driving member  30  disposed within the outer housing and outside the inner housing  10 , and a releasing assembly (which includes an ejection frame  40  and an ejection spring, wherein the ejection spring is not shown in the figures) disposed within the outer housing and outside the inner housing  10 . 
     The outer housing is configured to protect components disposed therein. An upper portion of the inner housing  10  defines a hopper  101 . The hopper  101  is configured to accommodate particulate matter. The distribution wheel  20  is disposed within an intermediate portion of the inner housing  10 . The bottom of the inner housing  10  has a releasing platform  112 . The driving member  30  is configured to drive the distribution wheel  20  to rotate. The distribution wheel  20  includes a circumferential surface and defines a recess  201  on the circumferential surface. The particulate matter in the hopper  101  may enter the recess  201  when the distribution wheel  20  is rotated to a position where an opening of the recess  201  is upward or diagonally upward. The particulate matter in the recess  201  falls onto the releasing platform  112  at the bottom of the inner housing  10  when the distribution wheel  20  is rotated to another position where the opening of the recess  201  is downward or obliquely downward. And then the releasing assembly releases the particulate matter falling onto the releasing platform  112  to feed the pet. 
     Next, a specific structure of the inner housing  10 , the distribution wheel  20 , the driving member  30 , and the releasing assembly will be described in detail one by one. 
     &lt;Inner Housing  10 &gt; 
     As shown in  FIG.  2   , the inner housing  10  includes a first shell  11 , a second shell  12 , and a baffle  13 . An upper portion of the first shell  11  and an upper portion of the second shell  12  enclose to form the hopper  101 . The hopper  101  is configured to accommodate the particulate matter. For example, the particulate matter may be pet foods in grain form, such as cookies or lyophilized meat products. The baffle  13  is disposed within the hopper  101  and is able to swing within the hopper  101 . 
     As shown in  FIG.  3   ,  FIG.  3    a structural schematic view of a first shell shown in  FIG.  2   . A direction indicated by an arrow in  FIG.  3    is a rotational direction of the distribution wheel  20 . An inner wall of the first shell  11  is provided with a guiding plate  111 . A bottom portion of the first shell  11  is provided with a releasing platform  112 . The opening of the recess  201  faces a feed opening of the hopper  101  when the distribution wheel  20  is rotated to a position where the opening of the recess  201  is upward or diagonally upward, such that the particulate matter in the hopper  101  may enter the recess  201  of the distribution wheel  20 . The particulate matter received in the recess  201  may fall onto the releasing platform  112  under a guidance of the guiding plate  111  when the distribution wheel  20  is rotated to another position where the opening of the recess  201  is downward or obliquely downward. In addition, a lower portion of the first shell  11  also defines a first opening  113  corresponding to the releasing platform  112 . The releasing assembly releases the particulate matter to feed the pet through the first opening  113 . 
     As shown in  FIG.  3   , a width of the guiding plate  111  is equal to an axial width k of the recess  201 , or the width of the guiding plate  111  is slightly greater than the axial width k of the recess  201 , so that the particulate matter falling out of the recess  201  moves along the guiding plate  111  to reach the releasing platform  112 , so as to prevent the particulate matter from falling to other positions out of the releasing platform  112 . 
     As shown in  FIG.  4   ,  FIG.  4    is another exploded structural schematic view of the particulate matter releasing apparatus shown in  FIG.  1   . A lower portion of the second shell  12  defines an avoidance region  121  corresponding to the releasing platform  112 . The avoidance region  121  is configured to avoid the releasing assembly from being interfered. The releasing assembly may apply a force to the particulate matter falling onto the releasing platform  112  through the avoidance region  121  to release the particulate matter falling onto the releasing platform  112 . 
     The baffle  13  may be rotationally connected, such as hinged, to the first shell  11  and/or the second shell  12  to enable the baffle  13  to swing within the hopper  101 . On one hand, a swing of the baffle  13  may toggle the particulate matter within the hopper  101  to avoid a situation that the particulate matter gets stuck in the hopper  101  and cannot enter the recess  201  of the distribution wheel  20 . On the other hand, the swing of the baffle  13  may also help to avoid a situation that the particulate matter gets stuck between the baffle  13  and the distribution wheel  20 . 
     The baffle  13  may have certain elasticity. The present disclosure do not limited a specific material of the baffle  13 , and any one skilled in the art may choose depending on an actual requirements. 
     In some embodiments, the inner housing  10  may also be excluded by the particulate matter releasing apparatus  100 . For example, there is only a channel, a conduit, or a container for guiding the particulate matter. In this situation, the distribution wheel may be fixed to the channel, the conduit, or the container described above directly or via a bracket. 
     &lt;Distribution Wheel  20 &gt; 
     The distribution wheel  20  is configured to dispense the particulate matter within the hopper  101  to the releasing platform  112 . Please refer to  FIG.  5   .  FIG.  5    is a structural schematic view of the distribution wheel shown in  FIG.  2   . A direction indicated by an arrow in  FIG.  5    is the rotational direction of the distribution wheel  20 . The recess  201  is defined on the circumferential surface of the distribution wheel  20 . The particulate matter within the hopper  101  may enter the recess  201  when the distribution wheel  20  is rotated to a position where the opening of the recess  201  is upward or diagonally upward. The particulate matter within the recess  201  falls onto the releasing platform  112  at the bottom of the inner housing  10  when the distribution wheel  20  is rotated to another position where the opening of the recess  201  is downward or obliquely downward. 
     Next, a shape of the recess  201  of the distribution wheel  20  will be described firstly. 
     In the embodiment, an opening size of the recess  201  may be less than a bottom size of the recess  201  to avoid a situation that the particulate matter in the recess  201  falls out of the opening of the recess  201  prematurely and cannot reach the releasing platform  112  when the distribution wheel  20  is rotated to a position where the opening of the recess  201  is downward or obliquely downward. 
     As shown in  FIG.  6   ,  FIG.  6    is a cross-sectional structural schematic view of the distribution wheel shown in  FIG.  5    along line A-A. A direction indicated by an arrow in  FIG.  6    is the rotational direction of the distribution wheel  20 . In the embodiment, the opening size of the recess  201  is less than the bottom size of the recess  201  may refer to a situation that the opening size L 1  of the recess  201  is less than the bottom size L 2  of the recess  201  in the rotational direction of the distribution wheel  20  (i. e., in a rotational direction of a part of the distribution wheel  20  which defines the recess  201 ). In other words, a width of the opening L 1  of the recess  201  is less than a width of the bottom L 2  of the recess  201  in the rotational direction of the distribution wheel  20 . In some embodiments, the opening size of the recess  201  is less than the bottom size of the recess  201  may also refer to a situation that the opening size of the recess  201  is less than the bottom size of the recess  201  in an axial direction of the distribution wheel  20  (i. e., a direction parallel to an axis of the distribution wheel  20 ). In other words, a width of the opening of the recess  201  is less than a width of the bottom of the recess  201  in the axial direction of the distribution wheel  20 . In some embodiments, the opening size of the recess  201  is less than the bottom size of the recess  201  may also refer to a situation that the opening size L 1  of the recess  201  is less than the bottom size L 2  of the recess  201  in the rotational direction of the distribution wheel  20 , and the opening size of the recess  201  is less than the bottom size of the recess  201  in the axial direction of the distribution wheel  20 . The present disclosure is not limited thereto, and any one skilled in the art may choose according to actual needs. 
     As shown in  FIG.  7   ,  FIG.  7    is the same view as  FIG.  6   . A direction indicated by an arrow in  FIG.  7    is the rotational direction of the distribution wheel  20 . In the embodiment, in a cross section of the distribution wheel  20  perpendicular to an axis of the distribution wheel  20 , a bottom center B 1  of the recess  201  is offset from a reference line B-B and is located at a front side of the reference line B-B in the rotational direction of the distribution wheel  20 , so as to avoid a situation that the particulate matter within the recess  201  falls out of the opening of the recess  201  prematurely and cannot reach the releasing platform  112  when the distribution wheel  20  is rotated to a position where the opening of the recess  201  is downward or obliquely downward. The reference line B-B passes through a geometric center B 2  of the recess  201  and an axial center B 3  of the distribution wheel  20 . 
     As shown in  FIG.  7   , in a case where the inner surface of the bottom wall  2013  is a plane surface, the bottom center B 1  of the distribution wheel  20  may refer to a midpoint of a line segment corresponding to the inner surface of the bottom wall  2013 . In a case where the inner surface of the bottom wall  2013  is a curved surface, the bottom center B 1  of the distribution wheel  20  may also refer to a midpoint of an arc segment corresponding to inner surface of the bottom wall  2013  in a cross-sectional view of the distribution wheel  20  perpendicular to the axis of the distribution wheel  20 . The present disclosure is not limited thereto, and any one skilled in the art may choose according to actual needs. 
     As shown in  FIG.  8   ,  FIG.  8    is the same view as  FIG.  6   . A direction indicated by an arrow in  FIG.  8    is the rotational direction of the distribution wheel  20 . In the embodiment, a bottom surface of the recess  201  is a plane (i. e., the inner surface of the bottom wall  2013  of the recess  201  is a plane). The geometric center B 2  of the recess  201  is offset from a reference surface C-C, and is located on a front side of the reference surface C-C in the rotational direction of the distribution wheel  20 , so as to avoid a situation that the particulate matter within the recess  201  falls out of the opening of the recess  201  prematurely and cannot reach the releasing platform  112  when the distribution wheel  20  is rotated to a position where the opening of the recess  201  is downward or obliquely downward. The reference surface C-C is an axial section of the distribution wheel  20  (i. e., a cross section of the distribution wheel  20  through the axis thereof) perpendicular to the bottom surface of the recess  201 . 
     With continued reference to  FIG.  6   , in the embodiment, in the rotational direction of the distribution wheel  20  (i. e., on a cross section of the distribution wheel  20  perpendicular to the axis of the distribution wheel  20 ), the recess  201  may include a first side wall  2011  and a second side wall  2012  disposed oppositely to each other. The first side wall  2011  is in front of the second side wall  2012  in the rotational direction of the distribution wheel  20 . That is, when the distribution wheel  20  is rotated to a position where the opening of the recess  201  is downward or obliquely downward, the particulate matter falls out of the recess  201  along the first side wall  2011 , and moves along the guiding plate  111  to reach the releasing platform  112 . In addition, the recess  201  may further include a bottom wall  2013  connecting the first side wall  2011  and the second side wall  2012 . 
     In the embodiment, in a direction from the opening of the recess  201  to the bottom of the recess  201 , the first side wall  2011  is gradually away from the second side wall  2012  to avoid a situation that the particulate matter within the recess  201  falls out of the opening of the recess  201  prematurely and cannot reach the releasing platform  112  when the distribution wheel  20  is rotated to a position where the opening of the recess  201  is downward or obliquely downward. 
     As shown in  FIG.  9   ,  FIG.  9    is the same view as  FIG.  6   . A direction indicated by an arrow in  FIG.  9    is the rotational direction of the distribution wheel  20 . In the embodiment, a top end of the first side wall  2011  is located at an intersection of a first reference surface D-D and a second reference surface E-E. The first reference surface D-D is a plane on which the opening of the recess  201  is located. In other words, the first reference surface D-D is flush with the opening of the recess  201 . The second reference surface E-E is perpendicular to the first reference surface D-D. The remaining portion of the first side wall  2011  other than the top end is located at a side of the second reference surface E-E away from the second side wall  2012 , so that when the distribution wheel  20  is rotated to a position where the opening of the recess  201  is downward or obliquely downward, the first side wall  2011  may retain the particulate matter in the recess  201  to prevent the particulate matter from falling out of the recess  201  along the first side wall  2011  prematurely. 
     Furthermore, as shown in  FIG.  9   , an inner surface of the first side wall  2011  is a curved surface. An angle α between a tangent plane of the inner surface of the first side wall  2011  and the first reference surface D-D is gradually increased in a direction away from the first reference surface. In this way, when the distribution wheel  20  is rotated to a position where the opening of the recess  201  is downward or obliquely downward, the first side wall  2011  may retain the particulate matter in the recess  201  better to ensure that the particulate matter within the recess  201  falls out of the recess  201  along the first side wall  2011 , and then moves along the guiding plate  111  to reach the releasing platform  112 . In some embodiments, the inner surface of first side wall  2011  may also be a straight surface. The present disclosure is not limited thereto, and any one skilled in the art may choose according to actual needs. 
     For example, the first side wall  2011  may extend along the circumferential surface of the distribution wheel  20  to retain the particulate matter in the recess  201  better when the distribution wheel  20  is rotated to a position where the opening of the recess  201  is downward or obliquely downward, so as to ensure that the particulate matter within the recess  201  falls out of the recess  201  along the first side wall  2011 , and then moves along the guiding plate  111  to reach the releasing platform  112 . 
     In order to reduce a processing difficulty of the distribution wheel  20 , an inner surface of the second side wall  2012  and an inner surface of the bottom wall  2013  of the recess  201  may also be provided as straight surfaces to facilitate processing and molding. The present disclosure is not limited thereto. In some embodiments, the inner surface of the second side wall  2012  and the inner surface of the bottom wall  2013  may also be curved surfaces, and any one skilled in the art may choose according to actual needs. 
     In the embodiment, a depth of the recess  201  occupies 30%-60% of a diameter of the distribution wheel  20  to ensure that the particulate matter within the recess  201  may smoothly reach the releasing platform  112  without falling out of the recess  201  in advance. For example, the depth of the recess  201  may occupy 30%, 40%, 50%, or 60% of the diameter of the distribution wheel  20 , which may be selected by any one skilled in the art according to actual needs. In a circumferential direction of the distribution wheel  20 , a width of the opening of the recess  201  occupies 15%-35% of a circumference of the distribution wheel, so that particulate matter within the hopper  101  may enter into the recess  201  smoothly. For example, in the circumferential direction of the distribution wheel  20 , the width of the opening of the recess  201  may occupy 15%, 20%, 25%, 30%, or 35% of the circumference of the distribution wheel  20 , which may be selected by any one skilled in the art according to actual needs. 
     As shown in  FIG.  10   ,  FIG.  10    is the same view as  FIG.  6   . A direction indicated by an arrow in  FIG.  10    is the rotational direction of the distribution wheel  20 . In the embodiment, an angle β between a tangent plane I-I of the circumferential surface of the distribution wheel  20  relative to a axial section F-F of the distribution wheel  20  and a tangent plane H-H of the inner surface of the first side wall  2011  relative to a same axial section F-F of the distribution wheel  20  is between 0-20° (i. e., the inner surface of the first side wall  2011  runs along the circumferential surface of the distribution wheel  20  generally). At a same recess depth, a distance between the first side wall  2011  and an axis of the distribution wheel  20  has a first rate of change, a distance between the second side wall  2012  and the axis of the distribution wheel  20  has a second rate of change. As shown in  FIG.  11   , at a certain recess depth defined by a plane marked as M-M, the distance between the first side wall  2011  and the axis of the distribution wheel  20  is marked as L 3 . In other words, a first intersection line is defined by the plane marked as M-M and the inner surface of the first side wall  2011 , the distance between the first side wall  2011  and the axis of the distribution wheel  20  refers to the distance between the first intersection line and the axis of the distribution wheel  20 . The distance between the second side wall  2012  and the axis of the distribution wheel  20  is marked as L 4 . In other words, a second intersection line is defined by the plane marked as M-M and the inner surface of the second side wall  2012 , the distance between the second side wall  2012  and the axis of the distribution wheel  20  refers to the distance between the second intersection line and the axis of the distribution wheel  20 . The first rate of change is less than the second rate of change, so as to retain the particulate matter in the recess  201  when the distribution wheel  20  is rotated to a position where the opening of the recess  201  is downward or obliquely downward, to ensure that the particulate matter within the recess  201  falls out of the recess  201  along the first side wall  2011 , and then moves along the guiding plate  111  to reach the releasing platform  112 . 
     As shown in  FIG.  10   , in the embodiment, an angle β between a tangent plane I-I of the circumferential surface of the distribution wheel  20  relative to a axial section F-F of the distribution wheel  20  and a tangent plane H-H of the inner surface of the first side wall  2011  relative to a same axial section F-F of the distribution wheel  20  is between 0-20° (i. e., the inner surface of the first side wall  2011  runs along the circumferential surface of the distribution wheel  20  generally). At a first recess depth, a ratio of a distance between the first side wall  2011  and the axis of the distribution wheel  20  and a distance between the second side wall  2012  and the axis of the distribution wheel is recorded as a first distance ratio. At a second recess depth, a ratio of a distance between the first side wall  2011  and the axis of the distribution wheel  20  and a distance between the second side wall  2012  and the axis of the distribution wheel  20  is recorded as a second distance ratio. The first distance ratio is less than the second distance ratio, the first recess depth is greater than the second recess depth, so as to retain the particulate matter in the recess  201  when the distribution wheel  20  is rotated to a position where the opening of the recess  201  is downward or obliquely downward, to ensure that the particulate matter within the recess  201  falls out of the recess  201  along the first side wall  2011 , and then moves along the guiding plate  111  to reach the releasing platform  112 . 
     As shown in  FIG.  6   , in the embodiment, at a same recess depth, the distance between the first side wall  2011  and the axis of the distribution wheel  20  is greater than the distance between the second side wall  2012  and the axis of the distribution wheel  20 . In other words, on the whole, the recess  201  is not symmetrical, but offset toward a front side of the rotational direction of the distribution wheel  20 , so as to retain the particulate matter in the recess  201  when the distribution wheel  20  is rotated to a position where the opening of the recess  201  is downward or obliquely downward, to ensure that the particulate matter within the recess  201  falls out of the recess  201  along the first side wall  2011 , and then moves along the guiding plate  111  to reach the releasing platform  112 . 
     Next, the specific structure of the distribution wheel  20  will be described. 
     Please refer to  FIG.  5    and  FIG.  12   .  FIG.  12    is an exploded structural schematic view of the distribution wheel shown in  FIG.  5   . A direction indicated by an arrow in  FIG.  12    is the rotational direction of the distribution wheel  20 . Since the recess  201  defined on the distribution wheel  20  has a certain depth, it is difficult to manufacture the distribution wheel  20  directly. In the embodiment, the distribution wheel  20  may be assembled from a first seat  21  and a second seat  22 . The first seat  21  defines a first groove  211 . The second seat  22  defines a second groove  212 . The first groove  211  and second groove  212  are communicated with each other to form the recess  201  together, so as to reduce the processing difficulty of the recess  201 . 
     As shown in  FIG.  5    and  FIG.  12   , in the rotational direction of the distribution wheel  20 , the recess  201  defines a first edge  207  (i. e., an end of the first side wall  2011  away from the bottom wall  2013 ) and a second edge  208  (i. e., an end of the second side wall  2011  away from the bottom wall  2013 ) spaced apart from each other. The second edge  208  locates behind the first edge  207  in the rotational direction of the distribution wheel  20 . A width of the second edge  208  is greater than a width of the first edge  207 . The second edge  208  has a preset width to facilitate an assembly of the first seat  21  and the second seat  22 . 
     As shown in  FIG.  5   , in the embodiment, a resilient member (which is not shown in the figures) is provided on the circumferential surface of the distribution wheel  20 . The resilient member extends outward from the circumferential surface of the distribution wheel  20 . During a rotation of the distribution wheel  20 , the resilient member may interfere with the baffle  13 , to drive the baffle  13  to swing within the hopper  101 . As a result, the baffle  13  may perturb the particulate matter within the hopper  101  to prevent the particulate matter from blocking the feed opening of the hopper  101 . 
     Specifically, the distribution wheel  20  may include two resilient members disposed symmetrically along the circumferential direction of the distribution wheel  20 , such that the distribution wheel  20  oscillates at a fixed frequency during a rotation thereof. In some embodiments, the number of the resilient member may also be one, three, four, or even more. The present disclosure is not limited thereto, and any one skilled in the art may select according to actual circumstances. 
     In the embodiment, the elastic member may be a spring. As shown in  FIG.  5   , the circumferential surface of the distribution wheel  20  may be provided with a mounting post  202 . The mounting post  202  may be inwardly recessed with respect to the circumferential surface of the distribution wheel  20 . The spring (which is not shown on figures) may be set on the mounting post  202 . An extension end of the spring extends outwardly to toggle the baffle  13 , and drive the baffle  13  to swing within the hopper  101 . In some embodiments, the resilient member may be other structures having certain elasticity, and capable of toggling the shutter  13 . The present disclosure is not limited thereto, and any one skilled in the art may select according to actual needs. 
     Furthermore, as shown in  FIG.  5   , a receiving groove  203  is defined on the circumferential surface of the distribution wheel  20 . The receiving groove  203  is corresponding to the spring. During a rotation of the distribution wheel  20 , the extension end of the spring interferes with the guiding plate  111 . When squeezed by the guiding plate  111 , the extension end of the spring may be received in the receiving groove, to prevent the distribution wheel  20  from being jammed. 
     Please refer to  FIG.  2    and  FIG.  5    together. In the embodiment, the distribution wheel  20  includes a first end  204  and a second end  205  disposed oppositely to each other along an axial direction of the distribution wheel  20 . The first end  204  is connected to the first shell  11 . The second end  205  is connected to the driving member  30 . The driving member  30  drives the distribution wheel  20  to rotate. 
     In the embodiment, an end surface of the second end  205  of the distribution wheel  20  is provided with an extending wall  206 . The extending wall  206  extends outward from the end surface of the second end  205  in an axial direction of the distribution wheel  20 . The extending wall  206  extends in the circumferential direction of the distribution wheel  20 . In the rotational direction of the distribution wheel  20 , a height of the extending wall  206  (i. e., the distance between an end of the extending wall  206  away from the end surface of the second end  205  and the end surface of the second end  205 ) decreases gradually first and then increases sharply. In other words, the extending wall  206  is disposed as a spiral line, to drive the release assembly to release the particulate matter on the release platform  112 . 
     As mentioned above, in the embodiment, the driving member  30  is connected to the second end  205  of the distribution wheel  20  on which the extending wall  206  is provided. In some embodiments, the driving member  30  may also be connected to the first end  204 . The present disclosure is not limited thereto, and any one skilled in the art may select according to actual needs. 
     In some embodiments, the extending wall  206  of the distribution wheel  20  may also be disposed in an involute manner with respect to an axis of the distribution wheel  20 . In the rotational direction of the distribution wheel  20 , a distance between the extending wall  206  and the axis of the distribution wheel  20  decreases gradually first and then increases sharply, to drive the release assembly to release the particulate matter on the release platform  112 . The present disclosure is not limited thereto, and any one skilled in the art may select according to actual needs. 
     In some embodiments, the extending wall  206  may also be excluded from distribution wheel  20 . For example, an end of the distribution wheel  20  may be connected with a cam. The cam rotates synchronously with the distribution wheel  20 , to drive the releasing assembly to release the particulate matter on the releasing platform  112 . The present disclosure is not limited thereto, and any one skilled in the art may select according to actual needs. 
     &lt;Driving Member  30  and Releasing Assembly&gt; 
     With continued reference to  FIG.  2   , the driving member  30  may be a motor. An output shaft of the driving member  30  is connected to the second end  205  of the distribution wheel  20 , to drive the distribution wheel  20  to rotate. During a rotation of the distribution wheel  20 , the extending wall  206  or the cam disposed on the second end  205  drive the releasing assembly to release the particulate matter on the releasing platform  112 . 
     With continued reference to  FIG.  2   , in the embodiment, the releasing assembly may include an ejection frame  40  and an ejection spring (which is not shown in the figures). The ejection frame  40  is rotationally connected to the second shell  12 , and may swing relative to the second shell  12 , to move away from or close to the second shell  12 . One end of the ejection spring is connected to the ejection frame  40 . The other end of the ejection spring is connected to the outer housing. 
     During a rotation of the distribution wheel  20 , the extending wall  206  of the second end  205  of the distribution wheel  20  may push the ejection frame  40  to swing in a direction away from the second shell  12 , during which the ejection spring is compressed. Since the height of the extending wall  206  disposed on the second end  205  of the distribution wheel  20  decreases gradually first and then increases suddenly, when the ejection frame  40  swings to a preset magnitude in a direction away from the second shell  12 , the pushing force from the distribution wheel  20  disappears suddenly, the ejection spring drives the ejection frame  40  to swing back (i. e., the ejection frame  40  swing towards the second shell  12 ), a baffle  41  disposed at a bottom of the ejection frame  40  extends into the inner housing  10  via the avoidance region  121  defined by the second shell  12 , to eject the particulate matter on the releasing platform  112  from the first opening  113  of the first shell  11 . 
     Specific structures of the particulate matter releasing apparatus  100  provided by the present disclosure are described above in detail. In addition, the inventor also designs tests to compare the feeding effect of the distribution wheel provided by the present disclosure with the distribution wheel in the related art. 
     Please refer to  FIG.  13   .  FIG.  13    is a schematic structural view of an embodiment of a distribution wheel in the related art. A direction indicated by an arrow in  FIG.  13    is the rotational direction of the distribution wheel  20   a . The recess  201   a  of the distribution wheel  20   a  in the related art also includes a first wall  2011   a , a second wall  2012   a , and a bottom wall  2013   a  connecting the first wall  2011   a  and second side wall  2012   a , but the specific structure is different from the present disclosure. 
     Specifically, as shown in  FIG.  13   , an opening size of the recess  201   a  is larger than a bottom size of the recess  201   a  in the rotational direction of the distribution wheel  20   a  (i. e., in a rotational direction of a part of the distribution wheel  20   a  which defines the recess  201   a ). A size of the recess  201   a  gradually decreases from the opening of the recess  201   a  to the bottom of the recess  201   a.    
     The distribution wheel  20  shown in  FIG.  5    and the distribution wheel  20   a  shown in  FIG.  13    are used to carry out feeding tests on two kinds of pet snacks sold in the markets by control variables. 
     Among them, one kind of the pet snacks is pet cookies, which are brittle cookie products with a size of 28.5 mm*12.2 mm*6.6 mm. The other kind of the pet snacks is lyophilized snacks, which are dehydrated meat products with certain resilience. The lyophilized snacks has a size of 13.3 mm*13.0 mm*10.0 mm. 
     One experimental statistical index is a number of the particulate matter taken out of the hopper by the distribution wheel at every time. Under ideal conditions, the number of the particulate matter taken out by the distribution wheel at every time should be consistent. The other experimental statistical index is a number of the particulate matter remaining on the releasing platform without being ejected out by the releasing assembly. Under ideal conditions, there should be no particulate matter remaining on the releasing platform. However, in practice, the shape of the recess may cause the distribution wheel to take too much particulate matter out of the hopper, as a result, the releasing assembly cannot eject all the particulate matter out, and a part of the particulate matter is remaining on the releasing platform. 
     The results of the statistical indexes of the  50  feeding tests on the pet cookies are shown in the table below: 
     
       
         
           
               
               
               
             
               
                   
               
               
                   
                 The variance of the number 
                 The average number of the 
               
               
                   
                 of the particulate matter 
                 particulate matter retaining 
               
               
                 Distribution 
                 taken by the distribution 
                 on the releasing platform 
               
               
                 wheel 
                 wheel of 50 feeding tests 
                 of 50 feeding tests 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
            
               
                 Distribution 
                 1.4384 
                 0.6 
               
               
                 wheel 20a of 
               
               
                 the related 
               
               
                 art (as shown 
               
               
                 in FIG. 13) 
               
               
                 Distribution 
                 0.5065 
                 0.28 
               
               
                 wheel 20 of 
               
               
                 the present 
               
               
                 disclosure (as 
               
               
                 shown in 
               
               
                 FIG. 5) 
               
               
                   
               
            
           
         
       
     
     It can be obtained from the analysis of experimental data shown above that: 
     The distribution wheel of the present disclosure has a lower variance of the number of the particulate matter taken by the distribution wheel, indicating that the number of the particulate matter taken by the distribution wheel has a small fluctuation in multiple feeding tests. In addition, the average number of the particulate matter retaining on the releasing platform of the distribution wheel of the present disclosure is also less than the distribution wheel of the related art. 
     The results of the statistical indexes of the  50  feeding tests on the lyophilized snacks are shown in the table below: 
     
       
         
           
               
               
               
             
               
                   
               
               
                   
                 The variance of the number 
                 The average number of the 
               
               
                   
                 of the particulate matter 
                 particulate matter retaining 
               
               
                 Distribution 
                 taken by the distribution 
                 on the releasing platform 
               
               
                 wheel 
                 wheel of 50 feeding tests 
                 of 50 feeding tests 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
            
               
                 Distribution 
                 1.4894 
                 0.64 
               
               
                 wheel 20a of 
               
               
                 the related 
               
               
                 art (as shown 
               
               
                 in FIG. 13) 
               
               
                 Distribution 
                 0.3792 
                 0.22 
               
               
                 wheel 20 of 
               
               
                 the present 
               
               
                 disclosure (as 
               
               
                 shown in 
               
               
                 FIG. 5) 
               
               
                   
               
            
           
         
       
     
     It can be obtained from the analysis of experimental data shown above that: 
     The distribution wheel of the present disclosure has a lower variance of the number of the particulate matter taken by the distribution wheel, indicating that the number of the particulate matter taken by the distribution wheel has a small fluctuation in multiple feeding tests. In addition, the average number of the particulate matter retaining on the releasing platform of the distribution wheel of the present disclosure is also less than the distribution wheel of the related art. 
     To sum up, for commonly used pet snacks, the performance of the distribution wheel of the present disclosure is better than the distribution wheel of the related art on both the evenness of the number of the particulate matter taken by the distribution wheel and whether the particulate matter is easy to be remained on the releasing platform. 
     The above description are only embodiments of the present disclosure, and do not limit the scope of the present disclosure. Any equivalent structure or equivalent process transformation made by using the contents of the description and drawings of the present disclosure, or directly or indirectly used in other related technical fields, are similarly included in the scope of patent protection of the present disclosure.