[0001] The present invention is for use in the marking of non-flat surfaces, particularly
in the food industry for marking eggs.
[0002] The marking of non-flat surfaces, particularly eggs, requires the stamp to have a
particular structure. Patent
US4314503 reveals a device for marking bottles containing a rim 22 with an printing membrane
16 stretched thereon, which comes in contact with the curve of an object, i.e. a bottle.
The printing membrane 16 is flat when at rest. Patent application
WO2007/062539 reveals a stamp for marking food products, particularly eggs, containing, amongst
others, a printing plate 4 mounted on a template 5, in the form of an ink-saturated
sponge. The printing plate 4 is spherical due to the shape imparted by the mounting
element 3 and template 5. A stamp is revealed by patent
EP1457108 possessing a template 3 in the form of a membrane with perforations 6 which allow
the passage of ink 5 and moistens the printing membrane 7 glued onto the template
3. The above mentioned solutions do not resolve the problem of delicate objects such
as eggs. The stiffening of a membrane with a template, either a sponge or a membrane,
may cause a loss of elasticity which may damage the eggs. The stretching of a membrane
on a drum is suitable only for printing on hard objects such as bottles. Moreover,
the use of glue for mounting printed film onto a template stiffens the membrane. The
print on a flat film becomes distorted following imprinting on a sphere, or the image
is incomplete. Thus there still remains a need to solve the problem entailing the
delivery of a stamp for non-flat surfaces, which would possess a non-flat membrane
surface elastic enough so as not to damage the delicate object and will easily assume
its shape during printing of the sign, which will not become distorted during printing,
where it will also be characterised by a sufficient elasticity of the layer with the
sign, which is smaller than the template. Unexpectedly, the present invention has
solved the abovementioned problem.
[0003] The subject of the present invention is a stamp for non-flat surfaces comprising
a case and a template , characterised in that the edges of the template are attached
to the case with the aid of a compression ring clamp. Equally preferentially, a stamp
according to the present invention, angle α of the edge bevel of the compression ring
clamp is from 20° to 30°. In the next equally preferential embodiment of the present
invention, the stamp is characterised in that the template is made of foamed polyolefin,
foamed EVA, latex or another soft material such as synthetic rubber. Equally preferentially,
a stamp according to the present invention, is characterised in that the diameter
of the case comprises at least 90% of the template diameter.
[0004] The second subject of the present invention is a method of producing the spheroid
shape of the printing template of the stamp, characterised in that it encompasses:
- a) connection of the template with the case,
- b) compression of the template onto the case with the aid of a compression ring clamp.
Equally preferentially, a method according to the present invention is characterised
in that stage (a) encompasses putting the edge of the template in contact parallel
to the side of the case cylinder. In the next preferential embodiment of the present
invention the method is characterised in that stage (b) encompasses the twisting or
compression or snapping shut the compression ring clamp with the case.
[0005] The present invention makes it possible to obtain a printing template with a spheroid
shape solely through its compression with a case of an appropriate shape. During printing
on, for example, an egg, it is important that the template be very soft, so as to
deform and adapt to the surface of the egg. In constructing it from a soft layer and
a "mould" as in earlier solutions, it lacked the required elasticity, which has been
achieved in the present invention. Heretofore, there has been a conflict between the
elasticity of the template itself and the mould: to shape the template along with
the mould, it had to have an appropriate elasticity, lesser than the template, otherwise
it would not be possible to shape it. If the mould was softer than the template, then
the template would impart its shape to it which was also not preferable. The use of
a highly elastic monolayer membrane in the present invention has solved the indicated
problems. The shape of the membrane is obtained by placing the membrane between the
case and compression ring clamp. Due to the fact that the edges of the template abutting
the case are parallel to the side of the case cylinder, the resulting shape of the
template in contact with an object is spheroidal, where it may be obtained only by
the edges of the compression ring clamp of the present invention. Moreover, extant
solutions made it impossible to expose a template already spherical, which must be
compressed during the exposure. Glueing the template onto a spherical mould and rendering
its shape was very difficult in practice. Moreover, the production of a template already
in the shape of a mould was very complicated, and therefore expensive, and a spheroid
template made it impossible to expose. The present invention has removed all these
problems through the use of a compression ring clamp of a characteristic shape, due
to which it was possible to place the edge of the template in parallel to the side
of the case cylinder.
[0006] The present invention has been illustrated in example embodiments shown in the attached
illustrations where Fig. 1 shows a lateral view of the stamp; Fig. 2 shows a longitudinal
section through the stamp without a mounted template, with the diameter A of the case
and a template not mounted in the stamp B, and Fig. 3 shows a longitudinal section
through the stamp with a mounted membrane.
[0007] Preferential embodiments of the present invention have been described below.
Example 1.
[0008] A stamp is composed of a case 1, to which is attached a template 2 found between
the case 1 and compression ring clamp 3. The edge of the template 2 on one side abuts,
in parallel, the side of the case cylinder 1, and on the other side the edge slant
of the compression ring clamp 3 with an angle α. The template 2 with the sign is made
of foamed polyolefin according to flash technology revealed in patents
US. Patent No. 5,858,298;
FR 69 90 1249,1-2307 ;
GB EE 3228, and
PL 180287 with subsequent amendments, consisting of thermocoupling fragments of microporous
material by transmitting a flash impulse of light from a xenon source through a printed
material and a separation film.
Example 2.
[0009] A method of producing the spheroid shape of the printing template encompasses the
placement of the printing template 2 on the case 1 parallel to the edge formed by
its rim. The template 2 with the compression ring clamp 3. As a result of pressure
applied to the compression ring clamp 3, the printing template assumes a spheroid
shape.
1. A stamp for non-flat surfaces containing a case(1) and a template(2), characterised in that the edges of the template(2) are attached to the case(1) using a compression ring
clamp(3).
2. A stamp according to Claim 1, characterised in that the angle α of the bevel of the compression ring clamp(3) is from 20° to 90°, preferentially
from 20° to 45°.
3. A stamp according to Claim 1 or 2, characterised in that the template(2) is composed of foamed polyolefin or foamed EVA.
4. A stamp according to any of Claims 1 to 3, characterised in that the diameter of the case A comprises at least 90% of the diameter B of the template(2).
5. A method of producing the spheroid shape of the printing template of the stamp,
characterised in that it encompasses:
a) attachment of the case (1) and template(2),
b) compression of the template(2) onto the case(1) using the compression ring clamp(3).
6. A method according to Claim 5, characterised in that stage (a) encompasses the placement of the edge of the template (2) parallel to the
side of the case (1)cylinder.
7. A method according to Claim 5 or 6, characterised in that stage (b) encompasses the twisting, compressing or snapping shut of the compression
ring clamp(3) onto the case(1).