Abstract:
A piston-type breast pump includes a piston-type pumping device, a DC motor, a gear reducer, and a control circuit board arranged in a housing. A gears rocking block ( 12 ) is connected with the piston-type pumping device, and far-near points induction chips and a buffering spring are provided between the block ( 12 ) and the reducer. A journey induction wheel is arranged at the motor shaft. A speed adjustment knob ( 35 ), a journey adjustment knob ( 34 ), a fast suck galactagogue button ( 33 ), and a suction adjustment screw are provided at the outer surface of the housing. The main body of the breast pump is a vertical design, and is constructed with a recessed bottle location ( 37 ), and the bottle holder ( 36 ) is removable.

Description:
BACKGROUND OF THE PRESENT INVENTION 
       [0001]    1. Field of Invention 
         [0002]    The present invention relates to a breast pump for human, and more particularly to a piston-type breast pump for human. 
         [0003]    2. Description of Related Arts 
         [0004]    Conventional breast pumps are divided into two types, the membrane type or the piston type. The membrane type has a simple structural construction and is easy to use. However, the drawbacks are low flow volume and low efficiency, low pressure level, and requirement of fast pressing in order to generate intermittent vacuum condition. Manual operation will lead to tiredness of user, especially the hands. Electric operation fails to provide a rhythmic and sufficient sectional force for producing a suction effect, and the effect as produced is greatly different from a frequency of a suction effect of a baby. 
         [0005]    Piston-type breast pump has a greater stroke for the process and produce an effect which is more similar to a suction frequency of a baby. In view of suction force and efficiency, user complains about insufficient suction force and low efficiency for those marketed products. For some products, the suction force is large when tested without milking bottle kits but insufficient in actual use. 
         [0006]    On the other hand, piston-typed breast pump with high suction power is usually bulky and large in size which is not suitable for carriage, while those with compact size are of low suction power. In addition, the piston-type breast pump usually comes with problems of noise and vibration. In view of function, there is no such multi-functional breast pump which is adjustable for controlling speed, stroke of the process, or is capable of simulating a lactation promotion process, and provides overall suction power adjustment. In short, a breast pump which is high efficiency, high power, small size, silent, and controllable for multi-function still does not exist. 
       SUMMARY OF THE PRESENT INVENTION 
       [0007]    The invention is advantageous in that it provides a piston-type breast pump which has improved functions of which the breast pump has a small size, high efficiency, high suction force, low noise level and low vibration level while providing multi-functional modes. 
         [0008]    Additional advantages and features of the invention will become apparent from the description which follows, and may be realized by means of the instrumentalities and combinations particular point out in the appended claims. 
         [0009]    According to the present invention, the foregoing and other objects and advantages are attained by a piston-type breast pump which includes a housing and a piston-type pumping arrangement received in the housing, comprising a DC motor, a gear reducer and a control circuit which are received in the housing; a gear swing unit operatively communicated with the gear reducer and connected to the pumping arrangement; first and second position sensor plates for detecting a far point position and a near point position respectively provided between the gear swing unit and the gear reducer; a buffer spring connected to the gear swing unit; a stroke sensor wheel positioned on an axis member of the DC motor; a speed control button, process control button, a promoting lactation button and a suction adjustment screw positioned on an outer side of the housing; wherein the housing has a vertical design having an indented portion defining a bottle side support on the housing and comprising a bottle bottom support provided thereon in a detachable manner. 
         [0010]    The housing comprises a front housing member, a rear housing member and a bottom housing member for forming the housing, wherein the speed control button, the process control button and the promoting lactation button are provided on the front housing member and communicatively connected to the control circuit, wherein the bottle side support is constructed into a semicircle structure having a bottom end operatively connected with the bottle bottom support for retaining a milk bottle into position, wherein the front housing member further provides an output head arranged for connecting to the milk bottle through a bottle connecting tube, wherein the suction adjustment screw is positioned on the rear housing member. 
         [0011]    The gear reducer comprises an axis support connected to the bottom housing member; a first axis, a second axis, a gear swing core axis positioned and supported in sequence through an inclined surface defined through a supporting side of the axis support; a gear connected to a middle portion of the first axis; a gear pulley connected to an end portion of the first axis; a second gear provided to a middle portion of the second axis operatively connected to the gear of the first axis, a third gear provided at one end portion of the second gear complementary to a teeth surface of the gear swing unit; a gear swing axis provided at one end of the gear swing unit through which the piston-typed pumping arrangement is connected; a motor pulley connected to the gear pulley through a belt arranged for connecting the gear pulley to the DC motor, wherein the gear has a size smaller than the second gear, and the second gear has a size larger than the third gear. 
         [0012]    The piston-typed pumping arrangement comprises a cylinder defining a cylinder cavity, a piston unit operatively provided in the cylinder cavity; and an output tube and a connecting output provided at one end portion of the cylinder, wherein the output tube is connected to an output head of the front housing member, wherein a frame unit is connected to the bottom housing member while a control valve such as a throttle valve is supported through and provided on the frame unit, wherein the end portion of the cylinder is connected to the frame unit in a hinged manner, wherein the control valve is connected to the connecting output through the output tube. 
         [0013]    The bottle bottom support comprises a connecting leg and a position member, wherein the housing has a position groove and a connecting hole corresponding to a position of the connecting leg and the position member respectively, wherein the connecting leg has a position hole and an inclined surface provided thereon. 
         [0014]    The buffer spring is inserted to connecting to the gear swing core axis in an enclosed manner, wherein the buffer spring has two ends defining to force receiving portions which are provided to the gear swing unit and to the axis support respectively. 
         [0015]    Two photoelectric sensors are positioned corresponding to the first and second position sensor plates respectively in which the first and second position sensor plates have a protruded structural construction. One of the first and second position sensor plates is inserted into one of the grooves of the photoelectric sensor corresponding to the position sensor plates when the gear swing unit swings to a position corresponding to the particular position sensor plate for detecting a position of the gear swing unit. 
         [0016]    The stroke sensor wheel and the motor pulley are connected, wherein the stroke sensor wheel has two indented portions, wherein the stroke sensor wheel comprises photoelectric sensor corresponding to the stroke sensor wheel. 
         [0017]    The throttle valve has a valve body, a valve core and a suction adjustment screw for forming the throttle valve, wherein the valve core has a cone structure at a first end and a plurality of thread construction at second end opposite to the first end, wherein the valve body has a core receiving cavity arranged for receiving and connecting the valve core, wherein the valve body has an input opening and an output opening which are channeled through the core receiving cavity respectively, wherein the valve body is supported by the frame unit, wherein the suction adjustment screw is connected with the valve core and extended to penetrate to an outer side of the rear housing member, wherein the input opening is connected to the connecting output through a tube. 
         [0018]    The housing has a vertical design, which is, the piston suction arrangement, the gear reducer and the DC motor are orderly arranged in a vertical manner. 
         [0019]    The preferred embodiment of the present invention employs a low speed high power DC motor for providing driving force, a gear swing unit driving the forward and backward motion of the piston through a two-stage gear reducer, a buffer spring between the gear swing unit and the reducer arrangement, thereby the overall size is compact, while the suction force is large and the vibration and noise level are reduced. 
         [0020]    Still further objects and advantages will become apparent from a consideration of the ensuing description and drawings. 
         [0021]    These and other objectives, features, and advantages of the present invention will become apparent from the following detailed description, the accompanying drawings, and the appended claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0022]    The preferred embodiment of the present invention is further described in details with the following drawings. 
           [0023]      FIG. 1  is an exploded view of a piston-type breast pump according to a preferred embodiment of the present invention. 
           [0024]      FIG. 2  is an illustration of a piston-type breast pump after assembly according to the above preferred embodiment of the present invention. 
           [0025]      FIG. 3  is a front perspective view of a piston-type breast pump according to the above preferred embodiment of the present invention. 
           [0026]      FIG. 4  is a rear perspective view a piston-type breast pump of  FIG. 2  according to the above preferred embodiment of the present invention. 
           [0027]      FIG. 5  is a rear perspective view of a piston-type breast pump according to the above preferred embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0028]    Referring to  FIGS. 1 ,  3  and  4  of the drawings, a piston-type breast pump according to a preferred embodiment of the present invention, includes a transmission arrangement. The transmission arrangement includes a DC motor  11  having a motor axis, a motor pulley  2  coaxially connected to the DC motor  11  through the motor axis having two grooves, a gear pulley  6  driven by the motor pulley  2  in which two belts are provided on the two grooves respectively to drive the gear pulley  6 , a small gear, namely a first gear, defining a first axis  7  and connecting to the gear pulley through the first axis  7  of the first gear, a large gear, namely a second gear, defining a second axis  8  which is driven by the first gear through the first axis  7 , a small gear, namely a third gear  25 , connecting to the second gear through one end of the second axis  8 , and a gear swing unit  12  cooperatively connected with the third gear  25  in a gear-wheel manner. Preferably, an overall size of the transmission arrangement is minimized through presetting the transmission ratio of motor pulley to gear pulley, the transmission ratio of the first gear to the second gear, and the transmission ratio of the third gear  25  to the gear swing unit  12 . In particular, the three axes of the transmission arrangement, which are the motor axis, the first axis and the second axis, are aligned in one inclined plane for reducing the size and facilitating installation or assembly. 
         [0029]    Referring to  FIGS. 1 ,  3  and  4  of the drawings, the piston-type breast pump according to a preferred embodiment of the present invention includes a cylinder  45 , a frame unit  21  supporting the cylinder  45  in a suspending manner, a piston unit  44  pulling the cylinder  45  such that a vacuum condition is generated for the cylinder  45 , an output tube  47  connected to one end of the cylinder  45 , a housing comprising an output head  14  which is connected to the output tube  47 , a gear swing axis  46  of the gear swing unit  12  connected to the piston unit  44  in a suspending manner. The DC motor  11  drives the piston unit in a reciprocal and rotational manner, pushing the cylinder  45  to generate the vacuum condition adapted for providing an output through the output tube  47  and the output head  14 . 
         [0030]    Referring to  FIGS. 1 and 3  of the drawings, the piston-type breast pump according to a preferred embodiment of the present invention includes an axis support  49  supporting the DC motor  11 , a first and a second photoelectric sensors  26  positioned between the axis support  49  and the gear swing unit  12 , a first and a second position sensor plates  10  extended from the gear swing unit  12  corresponding to the first and the second photoelectric sensors  26  respectively defining a near point position at which the cylinder is at a first position and a far point position at which the cylinder is at a second position, and a control circuit. The gear swing unit  12  starts to rotate when the cylinder  45  is returned to the first position, thereby a first position sensor plate  10  is inserted into a first photoelectric sensor  26  and the DC motor  11  is initiated to having a forward rotational movement through the control circuit. Likewise, the gear swing unit  12  starts to rotate when the cylinder  45  is returned to the second position, thereby the second position sensor plate  10  is inserted into the second photoelectric sensor  26  and the DC motor  11  is initiated to having a backward rotational movement through the control circuit. Accordingly, the cylinder  45  is controlled to move to the first and the second positions in a controllable manner. 
         [0031]    As shown in  FIGS. 1 and 4  of the drawings, the motor pulley  2  is installed onto the motor axis of the DC motor  11 , and a stroke sensor wheel  1  affixed on the motor pulley  2 . The stroke sensor wheel  11  has two indented portions  3 . The DC motor  11  has a photoelectric sensor  4  provided on a cover portion of the DC motor  11 . The stroke sensor wheel  11  is arranged for rotating between two opposite poles of the photoelectric sensor  4 . The control circuit initiates a counting module thereof if the indented portion  3  detects the photoelectric sensor  4 , wherein ½ rotation cycle is counted for each detection. The cylinder  45  can be controlled through controlling a total rotation cycle of the DC motor, thereby an output value of vacuum level is controlled. The rotation cycle of the DC motor is adjusted through a stroke control button  34  to adjust a position of a potentiometer corresponding to an output of the stroke control button  34 . The control circuit reads an output voltage of the potentiometer which is corresponding to a continuous rotational cycle of the DC motor. The stroke sensor wheel  2  has two indented portions so as to increase a control level of stroke motion in a dedicate and accurate manner, such that a user will not easily sense a jumping motion between different level of stroke motion. The sensor is positioned on the motor axis of the DC motor, compared to positioning on the cylinder, an accuracy of the stroke motion is increased while the overall size is minimized. 
         [0032]    Referring to  FIG. 1  of the drawings, the cylinder further includes a connecting output  50  connecting to a control valve  23  (which is a throttle valve) through a connecting tube. The control valve  23  has a valve body  51 , a valve core  52  and a suction adjustment screw  56 . The valve core  52  has a cone structure at one end connecting to the valve body  51 . The valve body  51  has an input opening  54  and an output opening  55 . Ventilation flow is provided through a level of opening between the valve body  51  and the cone structure of the valve core  52 . The valve body  51  is provided on the frame unit  21 . The valve core is connected to the suction adjustment screw  56  to penetrate outside a rear housing member  20  of the housing, which is shown in  FIG. 5 . The control valve  23 , which is connected to the cylinder  45 , is arranged for adjusting an overall suction force of the breast pump, thereby providing a suction adjustment feature in additional to the stroke control, which is very useful to provide flexibility to fit the different users who may have different preferences for stroke frequency or level of suction force. When the control valve  23  is tightened, the cylinder  45  under a particular preset stroke level will provide the maximum suction force. When the control valve  23  is loosen, the suction force will be reduced because of air passage and the level of suction force is proportional to the degree of opening of the control valve  23 . 
         [0033]    Referring to  FIGS. 1 ,  2  and  3  of the drawings, a front housing member  19  of the housing further provides a speed control button  35  an the stroke control button  34 . The speed control button  35  is arranged for controlling a suction speed of the cylinder, which in turns control an efficiency and effectiveness of pumping breast milk while providing flexibilities to different user based on their habits. The control circuit detects the output voltage of the potentiometer which is corresponding to a voltage of the DC motor such that a rotational speed is adjusted. The function of the stroke control button  35  is described above. 
         [0034]    Referring to  FIG. 6  of the drawings, the front housing member  19  further provides a promoting lactation button  33  for fast suction. When the promoting lactation button  33  is pressed, the cylinder is promptly entered into a high frequency and short suction cycle process and is then returned to the speed and suction force level after a preset time period, which is a few seconds in this case. This is to simulate the two stage of breast feed action of a baby. In the first stage, the baby will suck at a high frequency which will stimulate and promote lactation. After a few second, the baby will suck at a low frequency and powerfully, which is the second stage. Accordingly, this is design to fit the need of a user when the need of promoting lactation is required. The promoting lactation button  33  can be pressed for any period of time to fit the need of the user. 
         [0035]    As shown in  FIG. 1 , a buffer spring  15  is provided between the axis support  49  and the gear swing unit  12 . The buffer spring  15  is inserted into a gear swing axis  18 , having a first end hooking onto a protruded portion of the axis support  49  and a second end hooking onto a protruded block  17  of the gear swing unit. When the gear swing unit  12  push the cylinder to return journey, the buffer spring  15  is compressed such that a buffering effect is provided. The application of the buffer spring  15  can effectively reduce the sudden increase in vibration speed and noise during the return process of the cylinder, thereby the speed of the cylinder is relatively steady through providing a load to the cylinder for both the forward process and the backward return process for providing a stable operation. The compressed spring of the cylinder at the forward process further provides auxiliary pushing force and hence reduces the maximum power of the DC motor. 
         [0036]    As shown in  FIGS. 1 ,  2  and  3  of the drawings, the housing is a self-standing construction which is compact in size and utilizes reduced surface area of a tabletop or surface. The housing has two indented portion defining two bottle side support  37 , each of which has a semicircular construction, arranged for supporting a side portion of a bottle  58  and a bottle bottom support  36 . The bottle bottom support  36  includes a connecting leg  59 ; and position members  60 ,  61  which is arranged for inserting into connecting holes  28 ,  31  of a bottom portion of the housing. The connecting leg  59  has a position hole  62  and a front inclined surface. The bottom housing member  18  of the housing has a marble position groove  30  through which the connecting leg  59  is inserted into for securing into position. When the bottle bottom support  36  is pulled out, the marble inside the marble position groove  30  will bounce, therefore the bottle bottom support  36  is a detachable unit. During carriage, the bottle bottom support  36  can be detached to minimize a size of the housing for packing. The detached bottle bottom support  36  can also be placed on top of a surface for supporting a positioning of a bottle  58 . 
         [0037]    The control method according to the preferred embodiment of the present invention employs a control of the DC motor through voltage and speed adjustment. Two inputs of the potentiometer are arranged for adjusting a speed of the DC motor and for adjusting a process of the cylinder respectively. The main MCU has an integrated AD. The PWM driving circuit is mainly responsible for adjusting the speed of the DC motor in which a high power FET is employed. The driving circuit of DC motor employs a high power DARLINGTON tube for assembling H-bridge circuit. The use of DARLINGTON tube is to ratify the limited driving force of single chip processor and to minimize interferences with the DC motor. 
         [0038]    According to the preferred embodiment of the present invention, voltage and speed control are employed in consideration of the followings. The power of DC motor is not large. The need of steady rotation of motor. The need of noise reduction. PWM is ideal for providing high efficiency with reduced level of heat generation, however, when PWM is used for speed management, motor is unable to operate in a steady or stable condition while noise level of the motor is increased. Accordingly, voltage and speed management is used in the preferred embodiment of the present invention. 
         [0039]    Three photoelectric sensor input are employed, namely near position photoelectric sensor, far position photoelectric sensor and DC motor counting photoelectric sensor. The three photoelectric sensors are arranged for providing output into I/Os of the single chip processor such that the single chip processor monitors on a real-time basis. The power supply includes two sources, which are internal power supply and external power supply to a relay through a resettable fuse respectively, for monitoring and control. In order to avoid interferences between the two sources, only one power source can be used at any one time. 
         [0040]    MCU is installed to control the process motion to avoid the piston being stuck with the cylinder. When the suction force is too large, motor will be stalled and the piston cannot be pulled into motion, while a large and continuous suction force may cause damage to a nipple. A timing process for preventing motor blockage will provide protection effect through releasing the suction force after a preset time period, preferably within a few second, through controlling a reverse rotational motion of the motor. 
         [0041]    One skilled in the art will understand that the embodiment of the present invention as shown in the drawings and described above is exemplary only and not intended to be limiting. 
         [0042]    It will thus be seen that the objects of the present invention have been fully and effectively accomplished. It embodiments have been shown and described for the purposes of illustrating the functional and structural principles of the present invention and is subject to change without departure from such principles. Therefore, this invention includes all modifications encompassed within the spirit and scope of the following claims.