GB2157626A - Die stamping assemblies - Google Patents

Abstract

A die stamp assembly has a positioning member (18) for positioning the assembly. A cavity in the positioning member (18) accommodates a carrier (34) for a die stamp. A head (2) for gripping the assembly supports a downwardly depending rod (4) which is screw-threaded at its lower end for screw-threaded engagement with the carrier (32). The rod (4) slidably engages the positioning member (18). A coil spring (10) urges the head away from the positioning member (18). A retaining washer (20) acts to imprison the positioning member (18) on the rod (4) but allows a degree of relative axial movement between the head (18) and the positioning member (18). <IMAGE>

Description

SPECIFICATION Die stamp assemblies The present invention relates to die stamp assemblies for supporting a die bearing matter to be printed.

Previously proposed die stamp assemblies include a block supporting a rubber die and carrying a handle. To print out the matter of the die, the rubber die is applied to an ink pad to receive ink and then stamped on to a paper or document as required. Also proposed are die stamp assemblies which are provided with a guide member for positioning the assembly accurately where the die is to be stamped and for holding the die parallel to the area of stamping while a stamping action takes place.

Such assemblies suffer from the disadvantage that they are custom-made and must be ordered as a complete unit from a workship or factory where the die is produced.

According to the present invention, there is provided a die stamp assembly comprising a positioning member for positioning the assembly and having a cavity for accomodating a carrier for a die stamp, a head for gripping the assembly, a rod having one end rigid with the head and having its opposite end screw- threaded for screw-threaded engagement with a said carrier, the rod slidably engaging the positioning member, resilient means urging the head away from the positioning member and a retaining means for imprisoning said positioning member or said rod, but alowing a degree of relative axial movement between said head and said positioning member.

A die stamp assembly embodying the present invention will now be described, by way of example, with reference to the accompanying diagrammatic drawings, in which: Figure 1 is an exploded view of a die stamp assembly; Figure 2 is a plan view of the assembly of Figure 1; and Figure 3 is a plan view of the die carrier of the assembly.

As shown in Figure 1, the assembly comprises a head 2 of plastics material. The head 2 is generally triangular in cross-section, but with rounded corners (see Figure 2) and is hollow having a closed upper end and open lower end. The under-side of the closed upper end carries a downwardly depending cylindrical projection 6, having an opening which is engaged by a stainless steel rod 4. Advantageously, the upper end of the rod 4 is knurled and forms an interference fit in the opening of the projection 6.

The lower end portion 8 of the rod 4 is screwthreaded. The rod supports a coiled spring 10, a moveable base 12 for the head 2, a hexagonal guide 14 for the base 12, a knurled member 16 supporting the guide, and a positioning member 18.

The movable base 12 is sized to enter the head 2 and to slide up and down inside the head 2 and thereby maintain the spring 10 imprisoned within the head 2. The base 12 has a hexagonal opening which is engaged by the hexagonal guide 14 to constrain the base for movement parallel to the axis of the rod 4.

The guide 14 in turn is internally screw-threaded and in screw-threaded engagement with a projecting cylindrical portion 16a of the knurled member 16.The portion 16a has a central opening which is slidably engaged by the rod 4.

The knurled member 16 has an inverted cup shaped portion 168 which has a knurled exterior and a fustroconical hollow interior.

The positioning member 18 is generally of rectangular configuration and has four feet 24, one at each corner. The member 18 has a pitched cover which supports a fustroconical spigot 36 arranged to matingly engage the fustroconical interior of the knurled member 16.

A locking washer 20 of plastics material is arranged to form an interference fit with the rod 4 and when forced onto the rod to a position beyond the screw-threaded end portion 8, holds the parts 10, 12, 16 and 18 imprisoned on the shaft 4.

Some play between the base 12 and the upper end of the head 2 exists so that with the positioning member 18 placed on a horizontal surface, the head 2 and thus the rod 4 in turn can be displaced downwardly to a limited extent against the bias of the spring 10. Upon release of the head 2, the spring 10 will act to raise the head 2 and therefore the rod 4 to its former position.

The carrier 22 is generally of rectangular configuration and is arranged to be accommodated within a cavity in the under- side of the positioning member. The carrier 22 supports an upstanding boss 28 having a central opening.A brass insert 30, having an outer knurled surface, is press fitted into the central opening. The insert 30 is internally screw-threaded to screw-threadedly engage the screw-threaded end portion 8 of the rod 4.

The under-side of the carrier 22 has a platform 38 with a roughened surface to receive a die. The platform is surrounded by a rectangular downwardly depending skirt 32.

A die (not shown), for example of the self-inking variety, is mounted on the platform 38 so that its raised surface projects below the skirt 32. The carrier 22 is caused to be screw- threadedly engaged by the end portion 8 of the rod until the carrer 22 is drawn up into the cavity defined by the positioning member 18.

The die stamp assembly is then ready for operation.ln operation, the legs 24 are rested on the surface to be stamped and the head is urged downwardly until the die makes contact with the surface to be stamped and leaves its inked impression on that surface. Upon release of the head, the die is retracted within the cavity of the positioning member 18 by the spring 10.

It will be appreciated that since the die carrier 22 can so readily be detached from the remainder of the assembly simply by an unscrewing action, the assembly without the die carrier can be sold over the counter in retail shops and only the die carrier supporting a die bearing the required data need be ordered from the factory or workshop.

Because the rubber die is supplied from the workshop or factory, together with the carrier, the firm securing and accurate positioning of the die in the die stamp assembly is ensured.

It will also be appreciated that when a pre-inked die (a porous die with ink impregnated therein) eventually reaches the end of its useful life, it can readily be replaced by returning only the carrier 22 to the factory or workshop.

Claims (11)

1. A die stamp assembly comprising a positioning member for positioning the assembly and having a cavity for accommodating a carrier for a die stamp, a head for gripping the assembly, a rod having one end rigid with the head and having its opposite end screw-threaded for screw-threaded engagement with a said carrier, the rod slidably engaging the positioning member, resilient means urging the head away from the positioning member and a retaining means for imprisoning said positioning member on said rod, but allowing a degree of relative axial movement between said head and said positioning member.

2. An assembly according to Claim I wherein the screw-threaded end of the rod bears its screwthread externally of the rod and wherein the carrier has an annular projection which is screw- threaded internally to receive the screw-threaded end of the rod.

3. An assembly according to Claim 2 wherein the internal screw-thread of said annular projection is defined by an internally screw-threaded metallic sleeve embedded in said projection.

4. An assembly according to any one of Claims 1 to 3, wherein the retaining means comprises an annular member force fitted on said rod.

5. An assembly according to any preceding Claim wherein said positioning member and said carrier are each of plastics material.

6. A die stamp assembly comprising a positioning member for positioning the assembly on a location to be imprinted, a guide member guided by said positioning member for movement towards or away from the said location, a die support member for carrying a die, and coupling means for coupling and decoupling the die support member from the guide member.

7. An assembly according to Claim 6 including biasing means for biasing the guide member away from said location.

8. An assembly according to Claim 6 or to Claim 7 wherein the coupling means comprises an internal screw-thread on one of said guide member and said die support and an external screw- thread on the other of said guide member and said die support.

9. An assembly according to any preceding Claim including a die rigid with said carrier or die support member.

10. An assembly according to Claim 9 wherein said die comprises a pre-inked die.

11. A die stamp assembly substantially as hereinbefore described with reference to the accompanying drawings.