Abstract:
A stencil stamp includes a number of stencils having openings with various shapes, with the stencils being individually attached to a housing of the stencil stamp so that the stencils can be easily and cleanly changed. The stencil stamp also includes a cover for preventing the evaporation of ink from a pad within the stencil stamp. In a first version, a stencil and/or the cover is slid into a slot within the housing. In a second version, the housing includes a threaded surface for the attachment of a stencil and/or the cover.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to rubber stamps, and, more particularly, to a stencil stamp set including a stamp device and a plurality of stencils for forming a plurality of different printed patterns. 
     2. Summary of the Background Art 
     The patent literature includes a number of descriptions of stencil stamps in which a stencil, including a perforated pattern defining an image to be printed, extends across a lower surface of a pad containing ink, with the stencil and the ink pad being tied together, to move together, as the stamp is used. For example, U.S. Pat. No. 4,986,175 describes a stamp which may be provided with a number of replaceable and removable stencils, which are releasably carried on a lower surface of the ink pad, preferably by means of a band. A compressible stand-off is placed at each end of the stencil, so that the stencil and ink pad can be moved along the surface of a document into the desired position before the ink is placed against the document. 
     U.S. Pat. No. 5,894,794 describes a stencil stamp in which the stencil extends past edges of the ink pad being formed upward along the sides of the ink pad. The stamp unit additionally includes a skirt member attached to the ink pad with the skirt member having a substrate formed with a through-hole at its center. Guides provided on the substrate of the skirt member guide the stencil sheet, and prevent the leakage of ink from corner portions of the stencil sheet. 
     U.S. Pat. No. 5,642,665 describes a stencil stamp assembly having a triangularly-shaped central member with an ink pad extending across its lower surface, and a plate member extending upward and inward, along each of the sloped sides of the triangularly-shaped central member. The stencil extends along the lower surface of the ink pad and upward between the central member and the plate member at each side of the central member. 
     U.S. Pat. No. 5,586,500 describes a stencil stamp that is provided with a plurality of individually replaceable stencil stamp blocks, each of which includes a stencil extending under an individual ink pad and upward along the ends of the ink pad. This multi-block arrangement can be used to produce multi-color images and to allow variations to be made in an image by changing certain of the blocks. 
     SUMMARY OF THE INVENTION 
     It is a first objective of the invention to provide stencil apparatus including a number of stencils having openings with various shapes, with the stencils being attached to a housing of the stencil apparatus rather than to the ink pad so that the stencils can be easily and cleanly changed, one for another. It is a second objective of the invention to provide stencil stamp apparatus including a cover that can be placed within the apparatus, either with a stencil or without a stencil, with the cover preventing the evaporation of ink from the pad. 
     In accordance with a first version of the invention, stencil stamp apparatus is provided wherein the stencil stamp apparatus includes a housing, a plunger, a spring, a plurality of stencils, and an attachment structure. The housing has an upper end with an upper hole and a lower end with a lower hole. The plunger has an upper end with a handle extending through the upper hole in the housing and the lower end with a porous pad for carrying ink. The plunger is mounted to slide within the housing between an upper position and a lower position. The spring holds the plunger in the upper position. In the plurality of stencils, each stencil has an opening defining a shape to be printed. The cover is attachable to close an opening at the lower end of the housing. The attachment structure removably holds one of the stencils adjacent to the lower hole of the housing, with the porous pad being held away from a stencil within the attachment structure, with the plunger in the upper position, and against the stencil with the plunger in the lower position. 
     In one embodiment to the invention, the attachment structure includes a slot extending into the housing from an opening at a front side of the housing with the cover and each of the stencils, including a plate slide-able into the slot with a tab extending outward through the opening in the front side of the housing. The cover may be slide-able into the slot along with one of the stencils. The tab of the cover and the tab of the stencil may then extend outward through different portions of the opening in the front side of the housing. The housing may be rectangularly shaped. 
     In a second embodiment of the housing, the attachment structure includes a first threaded surface extending around the lower hole in the housing and the cover of each of the stencils comprises a web and a second threaded surface engaging the first threaded surface. The housing may be cylindrically shaped. 
     In a third embodiment of the invention, the attachment structure comprises a first threaded surface extending around the lower hole of the housing with each of the stencils comprising a web, a second threaded surface engaging the first threaded surface, and a third threaded surface. The cover, in this case, comprises a fourth threaded surface engaging the third threaded surface. Again, the stencil stamp apparatus may be cylindrically shaped. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a stamp device built in accordance with a first embodiment of the invention; 
         FIG. 2  is a front elevation of the stamp device of  FIG. 1 ; 
         FIG. 3  is a right side elevation of the stamp device of  FIG. 1 ; 
         FIG. 4  is a rear elevation of the stamp device of  FIG. 1 ; 
         FIG. 5  is a plan view of the stamp device of  FIG. 1 ; 
         FIG. 6  is a bottom plan view of the stamp device of  FIG. 1 ; 
         FIG. 7  is a cross-sectional side elevation of the stamp device of  FIG. 1 , taken as indicated by section lines  7 - 7  in  FIG. 2 ; 
         FIG. 8  is a plan view of a set of stencils and an associated cover for use within the stamp device of  FIG. 1 ; 
         FIG. 9  is a plan view of an alternative stencil and an alternative cover for use within the stamp device of  FIG. 1 ; 
         FIG. 10  is a perspective view of a stamp device built in accordance with a second embodiment of the invention; 
         FIG. 11  is a front elevation of the stamp device of  FIG. 10 ; 
         FIG. 12  is a plan view of the stamp device of  FIG. 10 ; 
         FIG. 13  is a bottom plan view of the stamp device of  FIG. 10 ; 
         FIG. 14  is a cross-sectional side elevation of the stamp device of  FIG. 10 , taken as indicated by section lines  14 - 14  in  FIG. 11 ; 
         FIG. 15  is a plan view of a set of stencils and an associated cover for use with the stamp device of  FIG. 10 ; 
         FIG. 16  is a cross-sectional side elevation of a stencil from the set of stencils of  FIG. 15  attached to an alternative cover; 
         FIG. 17  is a cross-sectional side elevation of an alternative housing for a stamp device built in accordance with the second embodiment of the invention with a second alternative cover attached thereto; and 
         FIG. 18  is a cross-sectional side elevation of a third alternative stencil attached to a third alternative cover for use with the alternative housing of  FIG. 17 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Various external features of a stencil stamp  10  built in accordance with a first version of the invention will now be discussed with references being made to  FIGS. 1 through 6 , in which  FIG. 1  is a perspective view of the stencil stamp  10 ;  FIG. 2  is a front elevation thereof;  FIG. 3  is a right side elevation thereof; the left side elevation of the device is a mirror image of the right side elevation.  FIG. 4  is a rear elevation thereof;  FIG. 5  is a plan view thereof; and  FIG. 6  is a bottom plan view thereof. 
     The stencil stamp  10  includes a plunger  12  mounted to slide vertically within a housing  14  which is, for example, rectangular in shape. The housing  14  includes an upper end  16  with an upper hole  18  and a lower end  20  with a lower hole  22 , as shown particularly in  FIG. 6 . The stencil stamp  10  additionally includes a stencil  26 , removably held within an attachment structure  26  in the form of a slot  28  extending within the housing  14  adjacent the lower opening. The stencil  26  includes a plate portion  30  having an opening  32  exposing a substrate (not shown) under the stencil stamp  10  to a porous ink pad  34  within the stencil stamp  10 . 
     Various internal features of the stencil stamp  10  will now be discussed with reference being made to  FIG. 7 , which is a cross-sectional side elevation of the stencil stamp  10 , taken as indicated by section lines  7 - 7  in  FIG. 2 . 
     The plunger  12  is seen to comprise an upper end, having a handle  38  extending through the upper hole  18  of the housing  14  extending to hold the porous pad  34 . For assembly purposes, the handle  38  and the lower end portion  40  are shown as separate pieces that are adhesively attached to form the plunger  12 . The stencil stamp  12  additionally includes a coil spring  42  in an upper position, in which it is shown, with the porous pad  34  being held away from the stencil  26 . Manually depressing the handle  38  of the plunger  12 , moves the plunger downward into a lower position in which the porous pad  34  is held against the stencil  26  with the stencil  26  additionally being deflected downward to contact a substrate  44 , such as a sheet of paper, under the stencil stamp with ink from the porous pad  34  then being transferred through the opening  32  within the stencil  26  to the substrate  44 . 
       FIG. 8  is a plan view of a cover  46  and a set of stencils  48  including the stencil  26 , as described above and additional stencils  50 , having differently shaped openings  52  through which printed images can be formed. For example, the cover  46  and each of the stencils  48 , may be interchangeably inserted within the slot  54  shown in  FIG. 7  through an opening  56 , in the front surface  58  of the housing  14 . When the cover  46  is so inserted, a lower opening  22  within the housing  14  is closed to prevent the evaporation of ink held within the porous pad  34 . 
       FIG. 9  is a plan view of an alternative stencil  60  placed atop an alternative cover  62  forming a configuration that can be held within the slot  54 . The alternative stencil  60  and the alternative cover  62  include tab portions  64  and  66 , respectively that extend through separate parts of the slot  56 , shown in  FIG. 7 , allowing the stencil  60  and the cover  62  to be easily inserted and removed through this opening  56 . This arrangement allows the cover  62  to be inserted to prevent ink evaporation without requiring the removal of the stencil  60 . 
     External features of a stencil stamp  70 , built in accordance with a second embodiment of the invention, will now be discussed with reference being made to  FIGS. 10-13 .  FIG. 10  is a perspective view of the stencil stamp  70 , while  FIG. 11  is a front elevation thereof,  FIG. 12  is a plan view thereof; and  FIG. 13  is a bottom plan view thereof. The stencil stamp  70  includes a plunger  72 , a housing  74 , having a cylindrical shape, and a stencil  76 . The stencil  76  includes a lip  78  engaging an attachment surface  80  of the housing  74  and a web  82 , including an opening  84 , through which a porous ink carrying pad  86  is brought into contact with a substrate (not shown). 
       FIG. 14  is a cross-sectional side elevation of the stencil stamp  70 . The porous pad  86  and the lower portion  88  of the plunger  72  are cylindrical in shape. Other features of the stencil stamp  70  are as described above for the stencil stamp  10 . 
       FIG. 15  is a plan view of a cover  90  configured for use with the stencil stamp  70  together with a set of stencils  92 , including the stencil  76  described above and additional stencils  94 . The stencils  76  and  94  may be individually installed on the stencil stamp  70  to produce various ink patterns on a substrate. When the stencil stamp  70  is not in use, the cover  90  is preferably installed in place of the stencils  76  and  94  to prevent the evaporation of ink stored within the porous pad  86 . 
       FIG. 16  is a cross-sectional side elevation of the stencil  76  having an alternative cover  96  attached thereto. The alternative cover  96  includes a lip  98  engaging the attachment surface  78  of the stencil  76 . This configuration allows the cover  96  to be placed on the stencil  76 , or removed there from, without removing the stencil  76  from the stamp device  70 . 
       FIG. 17  is a cross-sectional side elevation of an alternative housing  100  for use within the stencil stamp built in accordance with the second embodiment of the invention, engaging an alternative stencil  102 . The alternative housing  100  is provided with a threaded surface  104  engaging a threaded surface  106  of the alternative stencil  102 . Preferably, the alternative stencil  102  is additionally provided with a noncircular outer surface  108 , having ridges or flutes to simplify the tightening and loosening of the threaded surfaces  104  and  106 . 
       FIG. 18  is a cross-sectional side elevation of an alternative stencil  110  provided with a threaded surface  112  for engaging the threaded surface  104  of the alternative housing  100  and, additionally, with a threaded surface  114  for engaging the threaded surface  116  of an alternative cover  118 . Preferably the alternative cover  118  is additionally provided with a noncircular outer surface  120 , while the alternative stencil  110  is provided with a noncircular outer surface  122 . 
     While the invention has been described in terms of preferred embodiments and versions thereof with some degree of specificity, it is understood that this description has been given only by way of example, and that many changes can be made without departing from the spirit and scope of the invention, as described in the appended claims.