Abstract:
A thread spool holding device has a plastic base plate that holds a series of preferably soft plastic spindles that can be introduced or removed from the base and can be arranged as needed by sliding along a slotted track of the base. Each spindle can hold a threaded spool and has a cross sectional configuration for gripping the center hole of the spool. The spindle ends can also hold a bobbin in tandem with a thread spool.

Description:
This application is a continuation of application Ser. No. 12/460,704, filed Jul. 22, 2009, now U.S. Pat. No. 7,992,819. 
    
    
     BACKGROUND OF THE INVENTION 
     This invention concerns sewing supplies and equipment. 
     Seamstress work, using one or more sewing machines, usually requires a collection of spools of different thread, as well as bobbins for the various spools, often holding thread particular to a spool. The spools and bobbins are often switched frequently on a sewing machine. 
     Quite a number of devices have been conceived to accommodate multiple spools and/or bobbins for retrieval and storage in sewing. These come in a wide variety of forms. See, for example, U.S. Pat. Nos. 5,913,485, 5,727,699, 4,351,458, 4,195,739, 4,029,241, 3,948,396, 3,738,590, 2,944,761, 1,508,105, 1,405,554, 470,328, 462,702 and Des. 146,869. See also U.S. Pat. Nos. 6,789,771, 4,094,415, 3,491,893 and 2,431,423 showing devices for holding other articles not related to sewing, but with certain mechanical features having some pertinence to the invention. 
     There is a need for a convenient, compact and versatile spool holder, preferably also for bobbins, to keep these items together and readily available for retrieval and storage. 
     SUMMARY OF THE INVENTION 
     The spool holder of the invention is simple in concept but highly versatile, compact and efficient in use. The holder comprises a base plate or rack that is narrow and elongated and formed of molded plastic material, preferably a material that is relatively rigid but with some degree of give. To this base plate are attached, via an elongated slot through the length of the base plate, a series of preferably rubbery spindles, each with a stem long enough to hold a thread spool and optionally a bobbin stacked at the end of the thread spool. The spindles have heads with a peripheral groove, formed by a pair of axially spaced apart rubbery discs, and the base plate has a hole, basically keyhole-shaped to receive the heads of inserted spindles. The spindles can then be entered into the slot, to be slid along the slot or track to desired positions. 
     The spindles preferably can be inserted from either face of the base plate, so that their stems extend at right angles from the base plate in either direction, allowing dense storage of thread spools. Each spindle stem is at least slightly laterally compressible (in some portion of its length) so as to exert a force within the core of each thread spool (and bobbin) when the thread spool is forced down over the spindle, slightly compressing and deforming some portion of the spindle. For this purpose the spindle stems in one embodiment have a U-shaped cross section, and can have a thickened region near the head. Spools and bobbins are held in place by frictional engagement with the spindle. 
     It is thus among the objects of the invention to enable versatile, dense storage of thread spools of different sizes, with a device that allows the user to adjust positions of spool-engaging spindles as desired, for efficient storage and retrieval of spindles, and preferably also bobbins. These and other objects, advantages and features of the invention will be apparent from the following description of a preferred embodiment, considered along with the accompanying drawings. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view showing a thread spool holder according to the invention, with spindles and spools attached. 
         FIG. 2  is a perspective view illustrating the manner in which a spool holder spindle is assembled into a base plate of the device. 
         FIG. 3  is a cross section view through the base plate, showing retention of a spindle. 
         FIG. 4  is detail view in perspective showing one of the spool holder spindles. 
         FIG. 5  is a cross section view showing the configuration of the stem of the spindle, taken in the plane  5 - 5  in  FIG. 4 . 
     
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
     In the drawings,  FIG. 1  shows a spool and bobbin holder device  10  of the invention, including a base plate or rack  12  formed of molded plastic material. This rack is elongated, and may be about eight to nine inches in length, more broadly between about six inches and fifteen inches in length. Other lengths can be selected for particular applications. As the drawing shows, the base plate has an elongated slot  14  within which are engaged a series of spool holder spindles  16 , which can be formed of a rubbery plastic material such as urethane. In one form the spindles are made from a thermoplastic elastomer, about 85 durometer on the A scale. The rack or bar  12  may be, for example, ABS  109  on the R scale. The spindles hold thread spools  17 . An individual spindle  16  is shown in  FIG. 4 . The spindle  16  has a grooved head  18 , with a groove  20  which preferably is annular, defined between two integral discs  22  and  24  on either side of the groove  20 . An integral stem or shaft, not seen in the drawings, extends axially between these discs. As shown in  FIGS. 4 and 5 , the spindle stem  26  in this preferred embodiment is generally U-shaped. This enables inward compressibility of the stem (to smaller effective diameter) for a spool  17  pushed onto the spindle, or for a bobbin. The spindle  16  is integrally molded and is somewhat flexible. It has a spindle stem  26  that extends essentially linearly from the head  18 . 
     As shown in  FIG. 1 , a significant number of thread spools  17 ,  17   a ,  17   b ,  17   c , etc. can be attached onto the device. In fact, the thread spools can be quite densely packed, into contact with one another as shown at  17   a  and  17   b , and the spindles  16  can be arranged as closely as permitted by the width of the spools. This position adjustment feature of the device, along with the ability to arrange the spindles  16  to extend in both opposed directions, each essentially at right angles to the plane of the base plate or bar, allows very dense storage of thread spools on the device when desired. 
       FIG. 2  demonstrates that the spindles  16  are assembled into the slot  14  of the base plate or rack  12  by inserting the spindle head  18  into a generally keyhole-shaped opening  28  in the base plate, alongside and contiguous with the slot  14 . The keyhole opening may be essentially a circular opening  28  with a narrow adjoining channel  30  leading into the slot  14 . The channel or gap  30  is just wide enough to allow the shaft  31  (see  FIG. 4 ) at the axial center of the head  18  to slide through when pushed in that direction by a user. Although the spindle heads  18  and the opening  28  are shown as circular, they could be other shapes, such as elliptical, square or rectangular. Circular is preferred, but the important feature is that the head be passed into an access opening which may be a similar shape to the head but in any event allows the head to pass through. Also important is that the gap  30  be narrow so as to engage the head while allowing its central shaft to slide through with one of the head discs  22 ,  24  adjacent to and engaged with each opposed face (front and back as seen in  FIG. 2 ) of the base plate. The circular shape provides for adequate gripping of the grooved head onto the plate edges  32 , while allowing for relatively easy sliding of the spindle via its head  18  along the length of the slot for repositioning the spindle as desired. Non-circular head shapes will operate but may experience binding more than the circular shape, which produces less contact with the plate edges  32  and allows for some rolling when sliding, avoiding binding. 
     Although the opening  28  for the spindle heads is shown set off to one side of the slot  14 , it could be otherwise positioned. For example, the hole could be centrally positioned on the slot, straddling both plate edges  32 , although this would require more care when an engaged spindle is slid past the opening, so as not to unintentionally dislodge the spindle. Also, such location of the hole would have the disadvantage of preventing the positioning of a spindle at that location when needed for storing thread spools densely on the device. The hole could be positioned at either extreme end of the slot, although again, this would eliminate those positions for retaining a spindle. 
       FIG. 3  shows the device of the invention in cross section, and illustrates a spindle  16  assembled into the slot  14  of the base plate or rack  12 . This cross section shows in more detail how the spindle is retained in place. The head  18  of the spindle straddles the slot  14 , with the plate edges  32  of the slot engaged in the annular groove of the spindle head  18 . The two discs  22  and  24  that form the head are shown on opposed sides of the base plate  12  and of the slot plate edges  32 . The spindle stem  26  extends out at right angles from the plane of the rack or plate  12 .  FIG. 3  also illustrates margins or border ridges  35  preferably bordering the slot region and spaced apart so as to define a track that closely fits to the head of the spindle. The track provides greater stability. 
       FIGS. 3 and 4  also show a feature of a preferred embodiment for retaining the thread end from a thread spool or a bobbin retained on a spindle. Although no thread spool or bobbin is shown in  FIG. 3  or  4 , these views show a side notch  38  in the side of one leg of the U-shaped spindle stem  26 , and also a similar notch  40  preferably included in the bottom of the U at the outer end of the spindle  26 . The notch  38  may be, for example, roughly ⅛ inch back from the end of the spindle  26 . The depth of each notch is minimal and can be, for example, 1 mm or less, and the width of each notch can be approximately similar. At the bottom of the end notch  40  is a slit in the plastic material of the U-shaped spindle stem  16 , this slit being shown at  42 .  FIG. 4 , though not showing a spool or bobbin, schematically indicates the manner in which the notches and slit are used. A thread end  44  is shown, the end of a spool or a bobbin of thread and extending off the spool or bobbin in the same direction as the thread is wound on the spool or bobbin. The thread is placed into the notch  38  and then, within the U shape of the spindle stem  26 , is brought up to the end notch  40  and pulled downwardly to engage the thread in the slit  42  to firmly retain the thread end in place. The slit  42  can be, for example, about ⅛ inch deep. Since the bobbin (or spool) is held firmly on the spindle, the thread end will be retained securely against unwinding. 
       FIG. 5  shows a spindle  16  in cross section, as seen generally in the plane  5 - 5  in  FIG. 4 . Another feature of the invention, as seen in  FIG. 5  and also in  FIG. 3 , is that the stem  26  of the spindle  16  in a preferred embodiment tapers to a larger dimension, i.e. a larger effective diameter, in a base portion  26   a  adjacent to the head  18 . This provides for a tighter, more positive gripping of the thread spool by its center core as the spool reaches the end of the spindle stem and is positioned close to or in contact with the base plate. In fact, the spindle stem  26  can be of a dimension to allow thread spools to freely slide over the outer regions of the stem, while becoming firmly engaged only at the base of the stem. The outer end of the spindle, although a thread spool might fit loosely over it, can firmly engage a bobbin  36  as shown in  FIG. 1 . The length of the spindles in a preferred embodiment preferably is sufficient for storing a bobbin outboard of a spool. Bobbins generally have a slightly smaller core diameter than thread spools. The length of the spindle stem is at least about two inches, and preferably, in the case of accommodating bobbins, at least about two and one-half inches and ideally about two and five-eighths inches to two and three-quarters inches. More broadly the length of the spindle stem should be in the range of about two inches to three inches, and preferably about two and one-half inches to three inches for accommodating bobbins. 
     The spindles can be used independently of the base plate or rack, to keep spools and bobbins together. 
     The invention encompasses variations to the preferred embodiment described. Although the spindles may be formed of a somewhat rubbery elastomer material, a harder plastic could be used. A surface friction characteristic is preferred. The base plate or rack  12  could be other than straight as shown; its elongated slot could be curved, compound-curved, or even in a circle or ellipse, interrupted with crossbars to hold the base plate together. 
     The above described preferred embodiments are intended to illustrate the principles of the invention, but not to limit its scope. Other embodiments and variations to these preferred embodiments will be apparent to those skilled in the art and may be made without departing from the spirit and scope of the invention as defined in the following claims.