Abstract:
Disclosed are an embroidery fabric clamping unit for use with an embroidery machine, and an embroidery machine comprising the same, which allow the embroidering of even embroidery fabrics of arbitrary shape. The embroidery fabric clamping unit comprises: a unit body having a joining part provided for attachment to and detachment from a work table of the embroidery machine; an embroidery fabric support table which is linked to the unit body and supports the embroidery fabric to be embroidered by the embroidery machine; a lever which is supported on the unit body, with the embroidery fabric placed in between, and is able to apply pressure to and release pressure from the embroidery fabric support table; and a lever driving part for driving the lever.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to an embroidery fabric clamping unit for an embroidery machine and an embroidery machine including the same, and more particularly, to an embroidery fabric clamping unit for an embroidery machine and an embroidery machine including the same which enable embroidering of embroidery fabrics having an arbitrary shape. 
       BACKGROUND ART 
       [0002]    An embroidery machine is an apparatus that automatically embroiders various patterns such as characters, figures, and images on raw fabrics using various colors of yarns. Embroidery machines are classified into single needle machines and multi needle machines according to the number of needles mounted thereon. 
         [0003]    Embroidery machines include an embroidery frame for setting embroidery fabrics such as raw fabrics. Korea Patent Publication No. 10-2004-91598 discloses an embroidery frame for setting a raw fabric which can prevent deformation of the embroidery frame. 
         [0004]    However, since the disclosed embroidery frame is one for setting a fabric itself, it is difficult to set ready-made-products such as shoes, bags, pants, and T-shirts whose sewing has been already completed. The reason is because a typical embroidery frame has a structure in which ready-made-products such as shoes could not be properly fixed because it is configured to clamp four edges of a raw fabric. 
       DETAILED DESCRIPTION 
     Technical Problems 
       [0005]    It is thus an object of the present invention to provide an embroidery fabric clamping unit for an embroidery machine and an embroidery machine including the same which enables embroidering of embroidery fabrics of arbitrary shape. 
       Technical Solutions 
       [0006]    The above object can be achieved by embroidery fabric clamping units for an embroidery machine which includes: a unit body including a joining part detachably disposed on a work table of the embroidery machine; one or more embroidery fabric support tables each coupled to the unit body and supporting an embroidery fabric to be embroidered by the embroidery machine; one or more levers each supported by the unit body and applying a pressure to a corresponding embroidery fabric support table or releasing the pressure from the corresponding embroider fabric support table across the embroidery fabric; and a lever driving part driving the one or more levers. Here, at least one of the one or more embroidery fabric support tables and the one or more levers are provided in plurality. Also, at least one of the one or more embroidery fabric support tables and the one or more levers are provided so that the gaps therebetween are adjustable. 
         [0007]    Furthermore, the unit body may include a lever support part supporting the one or more levers and detachably coupled to the unit body. 
         [0008]    Here, the one or more levers may be detachably coupled to the lever support part. 
         [0009]    Furthermore, the one or more levers may comprise an elastic material. 
         [0010]    Also, each of the one or more levers may pivotaly move between a clamping position where the embroidery fabric is clamped by pressing the embroidery fabric on the corresponding embroidery fabric support tables and a release position where the embroidery fabric is unclamped by being spaced from the clamping position. 
         [0011]    Also, the lever driving part may include: a pneumatic cylinder; a piston supported by the pneumatic cylinder and selectively applying a pressure to the one or more levers; and a foot switch selectively supplying air to the pneumatic cylinder. 
         [0012]    Here, the lever driving part may further comprise an elastic member allowing the one or more levers to be elastically biased to the release position. 
         [0013]    The above-mentioned object can be achieved by an embroidery machine which comprises: a work table on which a raw fabric to be embroidered or an embroidery fabric is disposed; an embroidery fabric clamping unit according to any one of claims  1  through  3  detachably mounted on the work table; a raw fabric setting frame for setting the raw fabric; and a needle embroidering the embroidery fabric clamped by the embroidery fabric clamping unit. 
       Advantageous Effects 
       [0014]    The embroidery fabric clamping unit for an embroidery machine and the embroidery machine including the same provide the following advantages. 
         [0015]    First, since ready-made-products such as shoes and bags can be embroidered through clamping, the usability of an embroidery machine can be enhanced. 
         [0016]    Second, since a gap between levers for clamping embroidery fabrics or embroidery fabric support tables can be adjusted, various shapes of embroidery fabrics can be clamped. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0017]      FIG. 1  is a front view illustrating an embroidery machine according to an embodiment of the present invention; 
           [0018]      FIG. 2  is a perspective side view illustrating an embroidery fabric clamping unit of the embroidery machine of  FIG. 1 ; 
           [0019]      FIG. 3  is a perspective plan view illustrating an embroidery fabric clamping unit of the embroidery machine of  FIG. 1 ; 
           [0020]      FIG. 4  is a perspective front view illustrating an embroidery fabric clamping unit of the embroidery machine of  FIG. 1 ; 
           [0021]      FIGS. 5 and 6  are views illustrating a clamping process of an embroidery fabric clamping unit of the embroidery machine of  FIG. 1 ; 
           [0022]      FIG. 7  is a plan view illustrating an embroidery fabric clamping unit of a second embodiment of the present invention; and 
           [0023]      FIGS. 8 through 10  are magnified views illustrating an embroidery fabric clamping unit of the embroidery machine of  FIG. 1 , which is attached with an elastic member. 
       
    
    
     BEST MODES FOR PRACTICING INVENTION 
       [0024]    Hereinafter, exemplary embodiments of an embroidery fabric clamping unit for an embroidery machine and an embroidery machine including the same will be described in detail with reference to the accompanying drawings. 
         [0025]    Referring to  FIG. 1 , an embroidery machine  1  includes a work table  10  that enables an embroidering work by moving embroidery fabrics E in the X or Y direction; a needle  20  stitching the embroidery fabrics E; a needle driving part  30  feeding a yarn for stitching and driving the needle  20 ; a main body  40  supporting the work table  10 ; and a user input part  50  inputting an embroidery pattern to be embroidered on the embroidery fabric and inputting a control command. 
         [0026]    Sports shoes are exemplified as embroidery fabrics in  FIG. 1 , and a bobbin wound with a bobbin thread is received in the sports shoes. 
         [0027]    Depending on an embodiment, the user input part  50  may be omitted. 
         [0028]    An embroidery fabric clamping unit  100  for clamping embroidery fabrics such as raw fabrics, shoes, bags, pants, and T-shirts may be detachably coupled to the work table  10 . 
         [0029]    If needed, a typical raw fabric setting frame (not shown) may be installed on the work table  10  to clamp a raw fabric at an edge thereof with a rectangular or circular shape. The raw fabric setting frame (not shown) may also be detachably installed on the work table  10 . 
         [0030]    As shown in  FIGS. 2 through 5 , the embroidery fabric clamping unit  100  for the embroidery machine according to the first embodiment of the present invention includes a unit body  140  detachably coupled to the work table  10 ; an embroidery fabric support table  110  supporting the embroidery fabrics E to be embroidered by the embroidery machine  1 ; a lever  120  applying a pressure to the embroidery fabric support table  110  or releasing a pressure from the embroidery fabric support table  110  when the embroidery fabrics are disposed therebetween; and a lever driving part  130  driving the lever  120 . 
         [0031]    The unit body  140  includes a joining part  143  coupled to the work table  10  and a connection part  145  connected to the embroidery fabric support table  110 . 
         [0032]    One or more joining holes  143   a  are formed in the joining part  143  to allow the joining part  143  to be coupled to the work table  10  by a coupling member (not shown), but embodiments are not limited thereto. For example, the joining part  143  may be coupled to the work table  10  by various coupling methods. 
         [0033]    One or more joining holes  146  are formed in the connection part  145  to allow the connection part  145  to be coupled to the embroidery fabric support table  110 . 
         [0034]    Each of the embroidery fabric support table  110  includes a connection end  111  connected to the connection part  145  of the unit body  140  and a contact end  113  contacting the embroidery fabrics E. 
         [0035]    The surface of the contact end  113  is processed to have a surface roughness for a larger contact frictional force against the embroidery fabrics E. 
         [0036]    Each lever  120  is supported by the unit body  140 . 
         [0037]    Each lever  120  includes an extension part  121  extending along the longitudinal direction; a bent part  123  bent toward the contact end  113 ; and a contact part  125  extending from the bent part  123  and facing the contact end  113 . The shape of the lever  120  may be modified as long as the lever  120  can clamp the embroidery fabrics E together with the embroidery fabric support table  110 . 
         [0038]    As shown in the drawing, the surface of the contact part  125  may be processed to have a surface roughness to generate a larger contact frictional force against the embroidery fabrics E. 
         [0039]    Here, the lever  120  may be formed of a metallic material such as aluminum and stainless steel. The lever  120  may also be formed of an elastic material. The elastic material may include plastic. 
         [0040]    When the lever  120  is formed of a metallic material, the lever  120  may be coated with an elastic material such as rubber, sponge, and plastic. 
         [0041]    The lever driving part  130  may drive the levers  120  using one of driving sources such as pneumatic, hydraulic, and electric motors. 
         [0042]    The unit body  140  may include a lever support part  150  for supporting the levers  120 . 
         [0043]    The lever support part  150  may be detachably provided to the unit body  140 . The lever support part  150  may be slidably provided to the unit body  140 . 
         [0044]    As shown in  FIGS. 2 and 4 , the lever support part  150  includes a lever insertion part which the lever  120  is inserted into, a lever clamping part  155  for clamping the lever  120  in the lever insertion part  153 , and a support body  151  for supporting the lever insertion part  153 . 
         [0045]    The lever insertion part  153  may have an insertion hole  153   a  for receiving the lever  120 . The lever  120  inserted into the insertion hole  153   a  is clamped by the lever clamping part  155  provided on one side of the lever insertion part  153 . The lever insertion part  153  may be omitted in certain embodiments. More specifically, as shown throughout the attached drawings, the lever  120  is not coupled to the support body  151  indirectly while it is inserted in the lever insertion part  153 , but may be directly coupled to the support body  151  without intervention of the lever insertion part  153 . 
         [0046]    The lever  120  may be replaced by unfastening the lever clamping part  155 . In other words, the lever  120  is detachably coupled to the lever support part  150 . 
         [0047]    The support body  151  may have an opening  151  a for receiving one end of the lever insertion part  153  such that the lever insertion part  153  receiving the lever  120  pivotaly moves between a clamping position C and a release position B that are described later. 
         [0048]    The lever insertion part  153  received in the opening  151  a is pivoted on a hinge  152  in the support body  151 . 
         [0049]    Accordingly, as shown in  FIGS. 5 and 6 , the lever  120  inserted into the lever insertion part  153  may apply a pressure to an embroidery fabric E, and may pivot between the clamping position C where the embroidery fabric is clamped and the release position B where the embroidery fabric is unclamped. The lever  120  may also vertically move instead of pivotaly moving. Also, the lever  120  may vertically slide along a guide rail (not shown). In other words, the lever  120  may slide between the clamping position C where the embroidery fabric is clamped and the release position B where the embroidery fabric is unclamped. 
         [0050]    As shown in  FIG. 2 , the support body  151  is disposed on the connection end  111  of the embroidery fabric support table  110 . 
         [0051]    A coupling hole (not shown) communicating with the joining hole  146  of the unit body  140  is formed in the connection end  111  of the embroidery fabric support table  110 . A slot  154  communicating with the joining hole  146  and the coupling hole (not shown) is formed in the support body  151 . The unit body  140 , the support  110 , and the support body  151  are coupled to each other by the coupling member penetrating the joining hole  146 , the coupling hole (not shown), and the slot  154 . 
         [0052]    Hereinafter, an example of the lever driving part  130  that drives the lever using a pneumatic pressure will be described in detail. As shown in  FIGS. 2 through 5 , the lever driving part  130  includes a pneumatic cylinder  132  including an air nipple  131 , and a piston  133  supported by the pneumatic cylinder  132  and selectively applying a pressure to the lever  120 . 
         [0053]    When air is injected through the air nipple  131 , the piston  133  downwardly moves to apply a pressure to the lever  120  toward the embroidery fabric support table  110 . 
         [0054]    When air injection through the air nipple  131  is interrupted, the piston  133  may enter into an idle state in which a pneumatic pressure is not applied to the lever  120 . 
         [0055]    As shown in  FIG. 5 , the lever driving part  130  may further include an elastic member  135  that restores the lever  120  to the release position B. When air injection is interrupted, the lever  120  may be restored to the release position B. 
         [0056]    As shown in  FIG. 2 , the elastic member  135  is disposed between an elastic member support piece  134  connected to the support body  151  and the end of the lever insertion part  153  penetrating the opening  151   a  of the support body  151 . The elastic member  135  may apply an elastic force to the lever insertion part  153  to allow the lever  120  to be elastically biased. In certain embodiments, the elastic force may be directly applied to the lever  120 . 
         [0057]    Here, the elastic member  135  may be disposed on the opposite side to the piston  133  across the hinge  152 . More specifically, the elastic member  135  may apply an elastic force to the end of the lever insertion part  153  such that the contact part  125  of the lever  120  pivots toward the release position B. That is, the elastic force F of the elastic member  135  is applied in the direction of the arrow as shown in  FIG. 5 . 
         [0058]    In certain embodiments, the elastic member  135  may also be disposed on the side of the piston based on the hinge  152 . In this case, the elastic force of the elastic member  135  should be applied in the opposite direction of the elastic force F shown in  FIG. 5 . 
         [0059]    Also, the lever driving part  130  may further include a switch (not shown) that can selectively supply air through the air nipple  131 . The switch (not shown) may be manually or automatically manipulated. 
         [0060]    When a manual manipulation method is adopted, the switch (not shown) may include a mechanical switch. 
         [0061]    The switch (not shown) may be provided as a foot switch (not shown) that is manipulated by a foot such that a user grips the embroidery fabric E by his/her hands and puts the embroidery fabric E between the lever  120  and the embroidery fabric E. 
         [0062]    The foot switch (not shown) may adopt a toggle switching method. That is, when a user steps on the foot switch (not shown) once, air is supplied, whereas, when a user steps on the foot switch once more, air supply is interrupted. 
         [0063]    When an automatic manipulation method is adopted, the lever driving part  130  includes a sensor (not shown) for sensing whether the embroidery fabric E exists between the embroidery fabric support table  100  and the lever  120 , and a controller (not shown) for control the switch (not shown) based on a sensed result of the sensor (not shown). 
         [0064]    Here, the switch (not shown) may be disposed between an air tank (not shown) storing air and the pneumatic cylinder  132 . The switch may include an electronic switch (not shown) supplying/interrupting air by receiving an electrical control signal from the controller (not shown). 
         [0065]    When the embroidery fabric E exists, the controller (not shown) may control the electronic switch (not shown) to be opened, thereby supplying air to the air nipple  131  (more precisely, to the pneumatic cylinder  132 ). 
         [0066]    On the other hand, when the embroidery fabric E does not exist, the controller may control the electronic switch to interrupt air supply. 
         [0067]    Here, the controller may be disposed in the embroidery machine  1 , and the controller installed in the embroidery machine  1  may automatically sense whether the embroidery fabric clamping unit  100  for the embroidery machine  1  is disposed on the work table  10 . The presence or absence of the clamping unit  100  is automatically sensed by disposing a contact sensor and a photo sensor on a joining part of the work table  10  and the clamping unit  100 . 
         [0068]    In  FIGS. 1 through 6 , the embroidery fabric support tables  110  and the levers  120  have been exemplified as disposed in pair, respectively, but embodiments are not limited thereto. 
         [0069]    For example, three or more embroidery fabric support tables  110  and levers  120  may be disposed, respectively. 
         [0070]    Also, in certain embodiments, one embroidery fabric support table  110  and two levers  120  may be disposed. 
         [0071]    Accordingly, the numbers and shapes of embroidery fabric support tables  110  and levers  120  may be modified as long as they can be engaged with each other across the embroidery fabric E to clamp the embroidery fabric E. 
         [0072]    As shown in  FIG. 3 , when the embroidery fabric support tables  110  and the levers  120  are disposed in pair to correspond to each other, respectively, a distance D between each pair of the embroidery fabric support tables  110  and the levers  120  can be adjusted. 
         [0073]    More specifically, as shown in  FIG. 3 , a plurality of the joining holes  146  by which the embroidery fabric support tables  110  and the levers  120  (the lever support part  150  to be exact) may be disposed in the unit body  140  in the direction of the distance D, and then the embroidery fabric support tables  110  and the levers  120  may be appropriately located according to the length of an embroidery fabric. Accordingly, the distance D may be adjusted using the coupling member S. 
         [0074]    The joining holes  146  may be disposed at a certain interval in the direction of the distance D. The interval between the joining holes  146  may also increase as becoming distant from a central line A in the direction of the distance D. This is for fine adjustment of the distance D near the central line A. 
         [0075]    The method of adjusting the distance D is merely an example. The method of adjusting the distance D between a pair of embroidery fabric support tables  110  may be modified in various manners. 
         [0076]    Hereinafter, an operation process of the embroidery fabric clamping unit  100  of the embroidery machine  1  will be described in detail with reference to  FIGS. 5 and 6 , 
         [0077]    First, a user may locate a portion of an embroidery fabric E (e.g., shoes) to be embroidered between the embroidery fabric support table  110  and the lever  120 . 
         [0078]    In the case of the above-described manual manipulation method, a user may step on the foot switch (not shown) to supply air to the pneumatic cylinder  132 . The piston  133  is projected by a pneumatic pressure to apply a pressure to the lever  120  (precisely, the lever insertion part  153 ). 
         [0079]    Thus, the lever  120  may pivot from the release position B of  FIG. 5  to the clamping position C where the embroidery fabric E is clamped. 
         [0080]    After the clamping, an embroidery command is inputted into the user input part  50  of the embroidery machine  1  to start embroidering. 
         [0081]    When the embroidering is completed, the user may step on the foot switch once again to interrupt the pneumatic pressure, and thus the lever  120  is restored to the release position B by an elastic force F of the elastic member  153 . 
         [0082]    Thereafter, the user takes out the embroidery fabric E between embroidery fabric support table  110  and the lever  120 . 
         [0083]    Accordingly, since even an embroidery fabric having an arbitrary shape can be automatically embroidered using the embroidery machine  1 , the usability of the embroidered machine  1  can significantly increase. 
         [0084]    In the case of the automatic manipulation method, the embroidery fabric clamping unit  100  of the embroidery machine  1  will be operated as follows. 
         [0085]    First, a user interposes a portion of an embroidery fabric E (e.g., shoes) to be embroidered between the embroidery fabric support table  110  and the lever  120 . The sensor (not shown) senses whether the embroidery fabric E is interposed between the lever  120  and the embroidery fabric support table  110 , and transmits a sensed result to the controller (not shown). 
         [0086]    The controller controls the electronic switch (not shown) to supply air and allow the piston  133  to apply a pressure to the lever  120 . 
         [0087]    When embroidering is completed, the controller controls the electronic switch to interrupt air supply. Thus, the lever  120  is spaced from the embroidery fabric support table  110  by the elastic member  135  to be restored to the release position B. 
         [0088]    Thereafter, the user takes out the embroidery fabric E that has been embroidered. 
         [0089]    As shown in  FIG. 7 , an embroidery fabric clamping unit for an embroidery machine according to a second embodiment of the present invention includes: a Y-shaped embroidery fabric support table  110   a ; and a lever  120   a  having a shape corresponding thereto. Other configuration of the embroidery fabric clamping unit according to the second embodiment of the present invention is similar to that of the clamping unit  100  of the first embodiment. 
         [0090]    When the embroidery fabric support table  110   a  and the lever  120   a  have a Y-shape, one pair of embroidery fabric support tables  110  and one pair of levers  120  shown in  FIGS. 1 through 5  may be replaced by the Y-shape of the embroidery fabric support table  110   a  and the lever  120   a.    
         [0091]    Here, a distance between a first branch  115  and a second branch  117  of the Y-shape embroidery fabric support table  110   a  may be adjusted. In this case, the distance may be adjusted according to the length of an embroidery fabric to more easily clamp the embroidery fabric. 
         [0092]    A distance between a first branch  126  and a second branch  127  of the lever  120   a  may also be adjusted like the embroidery fabric support table  110   a . Adjustment of the distance between the first branch  126  and the second branch  127  of the lever  120   a  may be performed by installing a rack on at least one of the first branch  126  and the second branch  127 , disposing a pinion engaged with the rack, and then turning the pinion. 
         [0093]    The method for adjusting the distance may be similar to a method for adjusting the size of the jaw of an adjustable-end wrench that is a tool for fastening or unfastening bolts or nuts, but embodiments are not limited thereto. Accordingly, various methods may be applied to adjust the distance. 
         [0094]      FIGS. 8 through 10  illustrate the lever  120  attached with an elastic member  160 . 
         [0095]    When the lever  120  applies a pressure to the embroidery fabric support table ( 110  of  FIG. 5 ), the elastic member  160  itself may be compressed to apply a larger pressure to the embroidery fabric (E of  FIG. 5 ). 
         [0096]    The elastic member  160  includes at least one of sponge, rubber, and plastic. 
         [0097]    As shown in  FIG. 9 , an elastic member  160   a  may have an increasing thickness as it becomes closer to the end of the contact part  125 . Since a gripping force between the lever  120  and the embroidery fabric support table ( 110  of  FIG. 5 ) may be reduced at the end of the contact part  125  due to the weight of an embroidery fabric, it may be necessary to complement the elastic force of the elastic member  160   a  at the end thereof. 
         [0098]    As shown in  FIG. 10 , elastic members  160   b  and  160   c  formed of different materials may be attached to the contact part  125  of the lever  120 . 
         [0099]    The modulus of elasticity of the elastic member  160   c  closer to the end of the contact part  125  of the lever  120  is preferably greater than that of the elastic member  160   b  distant from the end of the contact part  125 . The reason is the same as what is described with reference to  FIG. 9 . 
         [0100]    The embodiments described above are provided for illustration purposes only, and the person skilled in the art would appreciate that various modifications and equivalent embodiments are possible therefrom. 
         [0101]    While the present invention has been described with reference to the particular illustrative embodiment, it is not to be restricted by the above embodiment but only by the appended claims.