Subsurface Sign Assembly

The invention disclosed herein generally relates to a subsurface sign assembly of the type in which the exterior face plate of the sign is transparent and the graphics are located behind the face plate and visible through the face plate; and more specifically to a subsurface sign assembly that includes a sign plate that can be inserted behind and removed from behind a transparent face plate.

Subsurface sign assemblies typically are used in situations where the sign is subject to deterioration due to weather conditions, vandalism and other conditions. When the graphics of a sign are exposed on the visible surface of the sign, the graphics can be picked or scraped from the surface by valdalism, and the graphics are exposed to weather conditions, etc. which tend to deteriorate the color and other features of the graphics.

While subsurface sign assemblies tend to solve the problems of vandalism and atmospheric deterioration of sign graphics, the typical subsurface sign is a "permanent" assembly, in that the graphics are applied internally to the transparent face plate and the transparent face plate is permanently mounted to an opaque back plate. If the owner of the sign wishes to change the graphics of the sign, the sign must be removed and replaced with another sign bearing the desired graphics.

While various subsurface sign assemblies have been developed in which a sign plate that bears the sign graphics is positioned behind a transparent face plate, and which include the ability to remove the sign plate and to replace the sign plate with another sign plate bearing different graphics, the various structural arrangements of the prior art changeable subsurface sign assemblies have been visually displeasing and the structure which provides the changeable feature of such signs is visible to the observer, so that the observer can change the sign without authorization from the owner of the sign.

Briefly described, the present invention comprises a subsurface sign assembly which includes a back plate for mounting to a wall surface, etc., a transparent face plate which is congruent with respect to the back plate and which is mounted to the back plate in parallel spaced relationship by double surface adhesive strip material or similar spacer means which extend about most of the perimeter of the back plate and face plate, but which leaves a slot opening for the insertion of a sign plate between the back plate and the transparent face plate. An opaque border is formed on the inner surface of the transparent face plate about the perimeter of the face plate, and the opaque border overlies and hides the adhesive strip material from view through the transparent face plate. The sign plate is inserted through the slot opening between the back plate and face plate into the pocket formed therebetween by the doubleface adhesive strip material. Openings are formed through opposed edge portions of the sign plate, with the openings being hidden behind the opaque border of the transparent face plate. A withdrawal tool is provided which includes cleats or protrusions for engaging the opening of the sign plate, by inserting the tool between the back plate and face plate, adjacent the sign plate, so that a cleat of the tool is inserted into the opening of the sign plate, whereupon the tool can be pulled from the sign assembly and withdraws the sign plate from the pocket between the back plate and face plate. The sign graphics are applied to the surface of the sign plate that faces the transparent face plate.

Since the opaque border of the transparent face plate hides the peripheral edge portion of the sign plate, there is no visible indication about the transparent face plate that the sign plate can be withdrawn from the sign assembly, so that vandalism of the sign assembly is unlikely.

Thus, it is an object of this invention to provide a changeable subsurface sign assembly having the appearance of a single unit subsurface printed sign in which the sign graphics can be changed without removing the rest of the sign assembly from the support wall.

Another object of this invention is to provide a subsurface sign assembly with a removable sign plate that can be inserted into and withdrawn from a pocket formed by a transparent face plate mounted to a back plate, and which includes a withdrawal tool for insertion between the face plate and back plate adjacent the sign plate, for engaging and withdrawing the sign plate from the rest of the sign assembly.

Another object of this invention is to provide an inexpensive subsurface sign assembly which is neat in appearance, and which enables the graphics of the sign assembly to be changed substantially without visually indicating how the graphics can be changed.

Other objects, features and advantages of this invention will become apparent upon reading the following specification, when taken in conjunction with the accompanying drawings.

FIG. 1 is an exploded perspective illustration of the subsurface sign assembly.

FIG. 2 is a perspective exploded illustration of a corner of the subsurface sign assembly.

FIG. 3 is a side elevational view of the withdrawal tool.

FIG. 4 is an edge view of the withdrawal tool, illustrating how the tool is used to withdraw the sign plate from between the back plate and transparent face plate.

Referring now in more detail to the drawings, in which like numerals indicate like parts throughout the several views, FIG. 1 illustrates the subsurface sign assembly 10 which includes a back plate 11, a transparent face plate 12, a sign plate 13 and doubleface adhesive strip material 14. In the embodiment illustrated, back plate 11 and face plate 12 are approximately rectangular with rounded corners. Back plate 11 includes opposed side edges 16 and 17, top edge 18 and bottom edge 19. Face plate 12 includes similar side edges 21 and 22, top edge 23 and bottom edge 24. Back plate 11 and face plate 12 are congruent and are arranged in parallel overlying relationship so that their edges are coextensive.

Doubleface adhesive strip material 14 comprises strip material with adhesive applied to its opposite surfaces. The strip material is applied between the back plate 11 and face plate 12 at three of their four peripheral edge portions, in an approximate U-shape, leaving a pocket 25 between the back plate 11 and face plate 12. The uniform thickness of the doubleface adhesive strip material 14 maintains the back plate and face plate 12 in parallel relationship with respect to each other and maintains a space of uniform thickness between the back plate and face plate. Thus, the back plate 11, face plate 12 and strip material 14 form a frame assembly, with a slot opening 26 at the common edges 16 and 21 of the back plate and face plate.

A layer of opaque material, such as paint 28 is applied to the inside surface of face plate 12 about the edged portion at the perimeter of the face plate, so that the opaque material extends from the outer edge of the face plate 12 inwardly of the face plate. The width of the opaque material 28 is greater than the width of the adhesive strip material 14, so that the opaque material 28 extends inwardly beyond the inner edge of the adhesive strip material 14. Thus, the opaque material 28 forms a border about the frame assembly which hides the adhesive strip material 14 from view through the transparent face plate 12.

The border formed by the opaque material 28 also extends along the fourth edge portion 21 of the transparent face plate so that there is no indication from the front of the sign assembly that there is a slot opening formed by the adhesive strip material applied to three of the four edges of the sign assembly.

Sign plate 13 is of a thickness slightly less than the adhesive strip material, and therefore slightly less than the distance between base plate 11 and face plate 12, and of a height slightly less than the distance between the inner edges of the top and bottom spans 29 and 30 of the adhesive strip material but of a height slightly greater than the distance between the inner edges of the top and bottom spans 31 and 32 of the opaque border 28 of the face plate 12. Likewise, the sign plate 13 is of a width slightly less than the distance between the inside edge of the vertical span 33 of the adhesive strip material 14 to the opposite side edge 21 of the face plate 12, but slightly greater in width than the distance between the inner edge of the vertical span 35 of the border 28 and the inside edge of the other vertical span 36 of the border 28. With this arrangement, the top and bottom spans 31 and 32 and vertical spans 35 and 36 of border 28 will overlie and therefore hide the vertical and horizontal edges of sign plate 13 from view through transparent face plate 12.

In the embodiment illustrated herein, sign plate 13 includes side protrusions 40 and 41 which project beyond the opposite side edges of the sign plate, and openings 42 and 43 are formed in sign plate 13 at the protruding portions 40 and 41. The adhesive strip material 14 defines a recess 44 for receiving a protrusion 40 or 41. The openings 42 and 43 are spaced apart a distance so that the openings will be located behind the vertical spans 35 and 36 of the opaque border applied to transparent face plate 12 when sign plate 13 is in position within its pocket 25 of the frame assembly. Therefore, the edges of the sign plate as well as its protrusions and openings are hidden from view when the sign plate is properly located in its pocket 25 between the base plate and face plate of the frame assembly.

The adhesive strip material 14 does not have adhesive applied to its inner and outer edges, only to its broad surfaces that are applied to the back plate 11 and to face plate 12. Therefore, the outer perimeter of the frame assembly is smooth in appearance and to the touch. Likewise, the inner surfaces of the adhesive strip material which are contacted by the edges of the sign plate 13 are relatively smooth, so that sign plate 13 can be readily slid into and out of the pocket 25 formed by the base plate 11, adhesive strip material 14, and face plate 12.

As illustrated in FIGS. 3 and 4, a sign plate withdrawal tool 46 is provided for the purpose of withdrawing the sign plate 13 from the pocket 25 of the frame assembly. Withdrawal tool 46 is fabricated from flat sheet material and includes cleats or tabs 48 and 49 protruding from one end portion thereof. The cleats 48 and 49 are cut from the sheet material of the withdrawal tool 46 and are bent or angled outwardly from the plane of the sheet material, as best illustrated in FIG. 4. The cleats 48 and 49 are bent in opposite lateral directions from the plane of the sheet material. The end portion of the withdrawal tool that bears the cleats 48 and 49 is of a thickness small enough that permits it to be inserted in between base plate 11 and face plate 12, adjacent sign plate 13. The cleats 48 and 49 are bent in a longitudinal direction away from the direction of insertion of the tool into the frame assembly, so that the cleats will not inhibit the insertion movement of the tool. The cleats 48 and 49 tend to be compressed back toward the plane of the insertion tool as the tool is inserted into the frame assembly, but when one of the cleats 48 or 49 registers with an opening 42 or 43 at the open edge portion of the frame assembly, that cleat will be biased inwardly with respect to the opening. When the withdrawal tool is then pulled from the frame assembly, the cleat 48 or 49 which is in registration with the opening 42 or 43 will tend to pull the sign plate 13 from the pocket 25 formed between the base plate 11 and the face plate 12. In this manner, the sign plate 13 can be inserted manually and removed with withdrawal tool 46, as may be desired, to change the sign plate 13, and therefore change the graphics displayed by the sign assembly 10.

In order to provide a pleasing visual appearance, sign plate 13 is formed with a uniform color, as by applying paint to the surface of the sign plate that is to be visually exposed in the frame assembly, and lettering is then applied to the surface of the sign plate which is to be exposed. The lettering can be painted as by a stencil and a spray paint applied to the sign plate, or by other means, such as by the use of a release sheet with lettering applied thereto, with the lettering being removable from the release sheet by friction or by heat. Other means can be provided for the application of lettering or other graphics to the sign plate 13. In some instances, the sign plate 13 will have one message applied to one of its surfaces and another message applied to its opposite surface, so that the sign plate can be turned over to provide the alternate messages.

Although the adhesive strip material 14 has been disclosed as the spacer means for maintaining the back plate 11 and face plate 12 in parallel spaced relationship, the back plate can be formed with a raised rim that projects from its periphery toward the face plate, and the rim can be adhesively or mechanically fastened to the face plate. With this structural arrangement the rim of the back plate would function as the spacer means.

While this invention has been described in detail with particular reference to a preferred embodiment thereof, it will be understood that variations and modifications can be effected within the spirit and scope of the invention as described hereinbefore and as defined in the appended claims.