Abstract:
Disclosed is a seat pumping device for a vehicle. The seat pumping device includes: a housing; a return spring guide which is fixedly coupled to the housing and has an embedded return spring; a clutch cam which is rotatably accommodated in the housing; and a lever bracket which is partially accommodated in the return spring guide and coupled to the clutch cam so as to be rotated integrally with the clutch cam, in which the lever bracket is maintained spaced apart from the return spring guide by a separation support means, thereby improving operating characteristics of a lever handle.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to and the benefit of Korean Patent Application No. 10-2016-0025824 filed in the Korean Intellectual Property Office on Mar. 3, 2016, the entire contents of which are incorporated herein by reference. 
       TECHNICAL FIELD 
       [0002]    The present invention relates to a seat pumping device for a vehicle, and more particularly, to a seat pumping device for a vehicle which has a lever handle with improved operating characteristics. 
       BACKGROUND ART 
       [0003]    A seat pumping device for a vehicle in the related art refers to a device which is attached to a seat in order to allow an occupant seated in the seat to manually adjust a height of a seat cushion in accordance with his/her body type. When the occupant seated in the seat manipulates a lever handle, which is installed at a lateral side of the seat cushion, clockwise or counterclockwise, operating force of the lever handle is transmitted to a link mechanism through the seat pumping device, such that the seat cushion moves upward or downward in response to a direction in which the lever handle is manipulated. 
         [0004]    The seat pumping device for a vehicle has been publicly known through Korean Patent Nos. 10-0722849 and 10-0784620. 
         [0005]      FIG. 1  illustrates an example of the seat pumping device for a vehicle. However, the seat pumping device for a vehicle, which will be described with reference to  FIGS. 1 to 5 , is considered as the related art in the present specification, but the seat pumping device for a vehicle has not been publicly known, and it should be understood that a description of the seat pumping device for a vehicle is just made to explain the background for the purpose of deriving the present invention. 
         [0006]    A seat pumping device for a vehicle includes a lever bracket  100  which is integrally rotatably connected to a lever handle (not illustrated) manipulated by a user, a return spring guide  110  which accommodates return springs  112  that provide restoring force to the lever bracket  100 , a housing  120  which is installed in a seat cushion (not illustrated) and has a shape of a drum  122 , a clutch device  130  which is accommodated in the housing  120 , receives rotational manipulation force from the user through the lever bracket  100 , and transmits the rotational manipulation force, a brake device  140  which blocks reversely inputted torque and maintains an adjusted height of the seat cushion, and a housing cover  150  which is coupled to one side of the housing  120  and covers the housing  120 . 
         [0007]    One side of the return spring guide  110  may be formed in the form of a doughnut having a concave groove so as to accommodate the return springs  112 . 
         [0008]    The clutch device  130  includes a clutch cam  134  which is accommodated in a clutch drum  132 , a plurality of clutch rollers  136  which is installed between an outer circumferential surface of the clutch cam  134  and an inner circumferential surface of the clutch drum  132 , and clutch springs  138  which resiliently support the clutch rollers  136 . 
         [0009]    A plurality of coupling protrusions  135  is formed on one surface of the clutch cam  134  at a predetermined interval in a circumferential direction. 
         [0010]    A through hole  126 , into which the coupling protrusions  135  of the clutch cam  134  are inserted, is formed at a central portion of a bottom surface  124  of the drum  122  of the housing  120 . 
         [0011]    The lever bracket  100  may include a coupling drum  104  that protrudes in an axial direction. 
         [0012]    Referring to  FIG. 2 , a plurality of assembly holes  128  is formed at a predetermined interval in the circumferential direction at the periphery of the through hole  126  at the center of the bottom surface of the drum  122  of the housing  120 , and a plurality of assembly protrusions  114 , which is inserted into and coupled to the assembly holes  128  and protrudes in the axial direction, is formed on the return spring guide  110  so as to be disposed at a predetermined interval in the circumferential direction. The return springs  112  may be provided so as to surround an outer side of the assembly protrusions  114 . 
         [0013]    Therefore, when the assembly protrusions  114  of the return spring guide  110  are inserted into and coupled to the assembly holes  128  of the housing  120 , the return spring guide  110  comes into close contact with the bottom surface  124  of the drum  122  of the housing  120 , as illustrated in  FIG. 3 . In addition, the return spring guide  110  is fixedly coupled to the housing  120  so as not to be rotatable relative to the housing  120  by an interaction between the assembly holes  128  and the assembly protrusions  114 . 
         [0014]    Referring to  FIG. 4 , the coupling protrusions  135  of the clutch cam  134  protrude through the through hole  126  at the center of the housing  120 , and is integrally coupled to the lever bracket  100  by being inserted into the assembly holes formed in a bottom surface of the drum  104  of the lever bracket  100 . 
         [0015]    For example, the lever bracket  100  is integrally coupled to the coupling protrusions  135  of the clutch cam  134  by welding, such that the lever bracket  100  and the clutch cam  134  rotate together. 
         [0016]    A lever arm  102 , which is formed on the lever bracket  100  by being bent in the axial direction, is resiliently supported in the circumferential direction by the return springs  112  of the return spring guide  110 , such that when the lever bracket  100  is rotated as the user manipulates the lever handle, the return springs  112  are compressed by the lever arm  102  of the lever bracket  100 , and then provide elastic restoring force to the lever bracket  100 . 
         [0017]    However, as illustrated in  FIG. 5 , when the coupling protrusions  135  of the clutch cam  134  and the lever bracket  100  are coupled by welding, the lever bracket  100  excessively comes into close contact with an outer circumferential surface of the return spring guide  110 . Therefore, when the lever bracket  100  is rotated by the manipulation of the lever handle, the lever bracket  100  is rotated in the state in which the lever bracket  100  is excessively in close contact with the outer circumferential surface of the return spring guide  110 , and as a result, there is a problem in that excessive frictional force is generated between the lever bracket  100  and the outer circumferential surface of the return spring guide  110 , which causes deterioration in operating characteristics of the lever handle. 
       SUMMARY OF THE INVENTION 
       [0018]    The present invention has been made in an effort to provide a seat pumping device for a vehicle which is capable of improving operating characteristics of a lever handle by maintaining a state in which a lever bracket is spaced apart from a return spring guide at the time of assembling the lever bracket and a clutch cam. 
         [0019]    An exemplary embodiment of the present invention provides a seat pumping device including: a housing; a return spring guide which is fixedly coupled to the housing and has an embedded return spring; a clutch cam which is rotatably accommodated in the housing; and a lever bracket which is partially accommodated in the return spring guide and coupled to the clutch cam so as to be rotated integrally with the clutch cam, in which the lever bracket is maintained spaced apart from the return spring guide by a separation support means. 
         [0020]    The clutch cam may include a clutch cam body having a polygonal block shape, and the separation support means may include two seating projections which protrude in an axial direction from one surface of the clutch cam body and on which the lever bracket is seated. 
         [0021]    The two seating projections may have the same height in an axial direction. 
         [0022]    The two seating projections may be disposed symmetrically so as to be spaced apart from each other at a predetermined interval in a circumferential direction. 
         [0023]    The two seating projections may be formed in an arc block shape. 
         [0024]    Two coupling protrusions, which protrude in the axial direction and is integrally coupled to the lever bracket, may be formed on one surface of the clutch cam body. 
         [0025]    The two coupling protrusions and the two seating projections may be alternately disposed in the circumferential direction. 
         [0026]    The two coupling protrusions may have a quadrangular block shape, and may protrude to the same height in the axial direction. 
         [0027]    Heights to which the two coupling protrusions protrude in the axial direction may be greater than heights to which the two seating projections protrude in the axial direction. 
         [0028]    A through hole into which the two coupling protrusions and the two seating projections are penetratively inserted may be formed in the housing, and two first guide surfaces and two second guide surfaces, which guide rotations of the two coupling protrusions and the two seating projections, respectively, may be formed in the through hole. 
         [0029]    The housing may include a drum, and the through hole may be formed to penetrate a bottom surface of the drum. 
         [0030]    The first guide surface and the second guide surface may be alternately formed in the circumferential direction. 
         [0031]    A radius of the first guide surface may be greater than a radius of the second guide surface, and a rotation radius of the two coupling protrusions may be greater than a rotation radius of the two seating projections. 
         [0032]    According to the seat pumping device for a vehicle according to the exemplary embodiment of the present invention as described above, the seating projection, on which the lever bracket is seated, is formed on the clutch cam, such that when the coupling protrusion of the clutch cam is coupled to the lever bracket, the lever bracket is maintained spaced apart from the return spring guide while being seated on the seating projection of the clutch cam. Therefore, the lever bracket may smoothly rotate without creating frictional force with the return spring guide when the lever bracket is rotated by the manipulation of the lever handle, and as a result, it is possible to improve operating characteristics of the lever handle. 
         [0033]    The seating projection also serves to guide the rotation of the clutch cam, and the clutch cam is stably rotated together with the lever bracket, and as a result, it is possible to improve operability of the seat pumping device. 
         [0034]    The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0035]      FIG. 1  is an exploded perspective view of a seat pumping device for a vehicle in the related art. 
           [0036]      FIG. 2  is a top plan view of a housing and a return spring guide of the seat pumping device for a vehicle in the related art. 
           [0037]      FIG. 3  is a side view illustrating a state in which the housing and the return spring guide of the seat pumping device for a vehicle in the related art are coupled. 
           [0038]      FIG. 4  is a top plan view illustrating a state in which a clutch cam and a lever bracket are coupled to the return spring guide coupled to the housing of the seat pumping device for a vehicle in the related art. 
           [0039]      FIG. 5  is a side view illustrating a state in which the housing, the return spring guide, and the lever bracket of the seat pumping device for a vehicle in the related art are coupled. 
           [0040]      FIG. 6  is a perspective view of a clutch cam according to an exemplary embodiment of the present invention. 
           [0041]      FIG. 7  is a perspective view illustrating a state in which the clutch cam according to the exemplary embodiment of the present invention is coupled to a housing. 
           [0042]      FIG. 8  is a side view illustrating a state in which the clutch cam and a return spring guide are coupled to the housing according to the exemplary embodiment of the present invention. 
           [0043]      FIG. 9  is an enlarged view of main parts of a lever bracket and the return spring guide according to the exemplary embodiment of the present invention. 
       
    
    
       [0044]    It should be understood that the appended drawings are not necessarily to scale, presenting a somewhat simplified representation of various features illustrative of the basic principles of the invention. The specific design features of the present invention as disclosed herein, including, for example, specific dimensions, orientations, locations, and shapes will be determined in part by the particular intended application and use environment. 
         [0045]    In the figures, reference numbers refer to the same or equivalent parts of the present invention throughout several figures of the drawing. 
       DETAILED DESCRIPTION 
       [0046]    Hereinafter, an exemplary embodiment of the present invention will be described in detail with reference to the accompanying drawings. First, in denoting reference numerals to constituent elements of respective drawings, it should be noted that the same constituent elements will be designated by the same reference numerals, if possible, even though they are illustrated in different drawings. Further, in the following description of the present invention, a detailed description of publicly known configurations or functions incorporated herein will be omitted when it is determined that the detailed description may make the subject matter of the present invention unclear. Further, an exemplary embodiment of the present invention will be described below, but the technical spirit of the present invention is not limited thereto and may be modified and variously carried out by those skilled in the art. 
         [0047]    Referring to  FIG. 6 , a clutch cam  10 , which is applied to a seat pumping device for a vehicle according to an exemplary embodiment of the present invention, may include a clutch cam body  12  having a polygonal block shape. Here, the clutch cam  10  is a member inserted into the clutch drum  132  in  FIG. 1 . 
         [0048]    One or more wedge protrusions  14 , which protrude outward in a radial direction, may be formed on an outer circumferential surface of the clutch cam body  12 . 
         [0049]    A central hole  16 , which penetrates front and rear surfaces of the clutch cam body  12 , may be formed at a central portion of the clutch cam body  12 , and two coupling protrusions  18  may be formed symmetrically at the periphery of the central hole  16  at a predetermined interval in a circumferential direction. 
         [0050]    The two coupling protrusions  18  have a quadrangular block shape, and may be formed to protrude in an axial direction from one surface of the clutch cam body  12 . 
         [0051]    Heights to which the two coupling protrusions  18  protrude in the axial direction may be equal to each other. 
         [0052]    Two seating projections  19  may be formed symmetrically between the two coupling protrusions  18  at a predetermined interval in the circumferential direction. 
         [0053]    The two seating projections  19  may be formed to protrude in the axial direction from one surface of the clutch cam body  12 . 
         [0054]    The two seating projections  19  are formed in, but not limited to, an arc block shape. 
         [0055]    Heights to which the two seating projections  19  protrude in the axial direction may be equal to each other, and may be smaller than the heights to which the two coupling protrusions  18  protrude in the axial direction. 
         [0056]    The two seating projections  19  constitute a separation support means that allows a lever bracket, which will be described below, to be spaced apart from a return spring guide. 
         [0057]    Referring to  FIG. 7 , a housing  20  may include a drum  22 , and the drum  22  may be provided with a bottom surface  24 . 
         [0058]    A through hole  26 , which penetrates the bottom surface  24 , may be formed at a central portion of the bottom surface  24 . 
         [0059]    Two first guide surfaces  261 , which have an arc shape and guide rotations of the two coupling protrusions  18 , and two second guide surfaces  262 , which have an arc shape and guide rotations of the two seating projections  19 , may be provided in the through hole  26 . 
         [0060]    The first guide surface  261  and the second guide surface  262  may be continuously formed alternately in the circumferential direction. 
         [0061]    A radius of the first guide surface  261  may be greater than a radius of the second guide surface  262 , and a rotation radius of the two coupling protrusions  18  of which the rotation is guided by the first guide surfaces  261  may be greater than a rotation radius of the two seating projections  19  of which the rotation is guided by the second guide surfaces  262 . 
         [0062]    Referring to  FIG. 8 , a return spring guide  30 , which accommodates a return spring, may be fixedly coupled to the housing  20 , as described with reference to  FIG. 2 . 
         [0063]    The return spring guide  30  may be formed in a ring shape with a penetrated center, and a part of a lever bracket  40  may be inserted into the ring shape, such that the return spring guide  30  may be coupled to the two coupling protrusions  18  of the clutch cam  10  by welding. 
         [0064]    In this case, a bottom surface  42  of the lever bracket  40  may be seated on the two seating projections  19  of the clutch cam  10 , and as a result, one surface  42  of the lever bracket  40  in the axial direction is spaced apart from an outer circumferential surface  32  of the return spring guide  30  which faces the one surface  42  of the lever bracket  40 , thereby forming a separation gap a, as illustrated in  FIG. 9 . 
         [0065]    Therefore, the lever bracket  40  is rotated in a state of being spaced apart from the return spring guide  30  when the lever bracket  40  is rotated by the manipulation of a lever handle, and as a result, the lever bracket  40  does not cause friction with the return spring guide  30 , thereby improving rotation characteristics of the lever handle. 
         [0066]    When the lever bracket  40  is rotated by receiving rotational manipulation force from the lever handle, the clutch cam  10  is also rotated integrally with the lever bracket  40 . In this case, since the rotations of the two coupling protrusions  18  and the two seating projections  19  of the clutch cam  10  are guided by the first guide surfaces  261  and the second guide surfaces  262 , respectively, the rotations may be stably guided in comparison with a case in which rotations of three coupling protrusions are guided by three guide surfaces in the related art, and as a result, it is possible to improve operation reliability of the clutch cam  10  and the seat pumping device. 
         [0067]    As described above, the exemplary embodiments have been described and illustrated in the drawings and the specification. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and their practical application, to thereby enable others skilled in the art to make and utilize various exemplary embodiments of the present invention, as well as various alternatives and modifications thereof. As is evident from the foregoing description, certain aspects of the present invention are not limited by the particular details of the examples illustrated herein, and it is therefore contemplated that other modifications and applications, or equivalents thereof, will occur to those skilled in the art. Many changes, modifications, variations and other uses and applications of the present construction will, however, become apparent to those skilled in the art after considering the specification and the accompanying drawings. All such changes, modifications, variations and other uses and applications which do not depart from the spirit and scope of the invention are deemed to be covered by the invention which is limited only by the claims which follow.