Positioning device

A positioning device for accurately positioning a male die member of an embossing tool in relation to a female die member thereof comprises a housing element which is adapted to be temporarily fixed in a hole in the male die member and a holding element disposed movably in the housing element. The holding element is axially displaceable relative to the housing element between a position in which it projects into a hole in the male die member and temporarily fixes the male die member in position, and a position of being retracted into the housing element to release the male die member. Disposed between the housing element and the holding element is a spring which is mechanically stressed in the retracted position of the holding element.

FIELD OF THE INVENTION 
The invention concerns a positioning device for accurately positioning a 
male die member of an embossing tool and a female die member thereof in 
relation to each other. 
In this specification the term embossing tool is used for the sake of 
conciseness and brevity to denote for example embossing, stamping, coining 
or like tools involving a male and a female die member which are movable 
relative to each other to produce the required shape. 
BACKGROUND OF THE INVENTION 
It is a known practice for a male die member of an embossing tool to be 
positioned in relation to a female die member thereof by means of 
positioning devices in the form of pins which are inserted into 
appropriately corresponding holes in the female die member. Those pins may 
also be designed with spacer rings thereon. The positioning devices of 
that kind suffer from the shortcoming that the male die member is often 
not reliably held fast to the positioning devices and thus to the 
co-operating female die member. Disengagement of the male die member from 
the female die member in that way can cause serious problems. 
DE 28 10 093 A1 discloses a pressing or stamping apparatus having an upper 
block member and a lower block member which are movable towards and away 
from each other. A female die member is disposed on the lower block 
member. Projecting away from the upper block member is a male die member 
which is accurately fittingly oriented in relation to the female die 
member. The male die member extends through a pressure plate which is 
resiliently connected to the upper block member by means of a spring 
assembly in such a way that, upon actuation of the pressing or stamping 
apparatus, the pressure plate firstly comes to bear against the workpiece 
to be pressed or stamped in order securely to fix the workpiece in the 
appropriate position. Subsequently thereto, the male die member then comes 
into contact with the secured workpiece. The stamping operation, that is 
to say movement of the male die member into the female die member, then 
takes place as the upper block member moves closer towards the lower block 
member. In that arrangement the spring assembly which connects the 
pressure plate to the upper block member remains connected to the pressure 
plate at all times. 
GB 1 459 267 describes a pressing or stamping apparatus which has an upper 
block member and a lower block member. Mounted on the upper block member 
is a pressure plate which is disposed movably in relation to the upper 
block member, by way of a connecting means. A spring device is provided 
for resiliently movably connecting the pressure plate to the upper block 
member. That pressing or stamping apparatus also provides that the 
pressure plate is permanently connected to the upper block member by way 
of the above-mentioned connecting means. 
SUMMARY OF THE INVENTION 
An object of the present invention is to provide a positioning device for 
the die members of an embossing tool, which can provide for reliably 
holding the die members relative to each other. 
Another object of the present invent ion is to provide a positioning device 
for positioning a male die member of an embossing tool in relation to a 
female die member in secure but easily releasable relationship. 
Still another object of the present invention is to provide a positioning 
device for locating the die members of an embossing tool relative to each 
other which while providing for properly secured location of the die 
members relative to each other can be readily mounted to one of the die 
members for the subsequent positioning operation and thereafter can be 
readily removed from its mounted condition. 
In accordance with the principles of the present invention the foregoing 
and other objects are attained by a positioning device for accurately 
positioning a male die member of an embossing tool and a female die member 
thereof in relation to each other, comprising a housing means adapted to 
be temporarily fixed to one of the die members. A holding means is 
disposed in the housing means axially displaceably with respect to the 
housing means between a first position of engaging the other of the die 
members thereby to hold same fast, and a second position of being 
retracted into the housing means, thereby to release the other die member. 
A spring is operatively disposed between the housing means and the holding 
means and is adapted to be mechanically stressed in the second retracted 
position of the holding means. 
In another aspect of the invention the foregoing and other objects are 
achieved by a positioning device for positioning a male die member of an 
embossing tool in relation to a female die member thereof, comprising a 
housing element adapted to be temporarily fixed in a hole in the female 
die member, and a holding element disposed in the housing element and 
adapted to be axially displaceable with respect to the housing element 
between a first position in which it projects into a hole in the male die 
member and holds the male die member fast and a second position in which 
it is retracted into the housing element and releases the male die member, 
and a spring member operatively disposed between the housing element and 
the holding element and adapted to be mechanically stressed in said second 
retracted position of the holding element. 
As will be seen in greater detail hereinafter from a description of a 
preferred embodiment of the invention, the positioning device according to 
the invention enjoys the advantage that it is suitable for reliably 
holding a male die member in relation to the associated female die member 
and it is also advantageously suitable for automatically releasing the 
male die member again after accurate positioning of the male die member in 
relation to the female die member and fixing of the male die member to an 
associated component of the embossing tool. After the embossing tool 
component to which the male die member is fixed and a second component of 
the embossing tool to which the female die member is fixed have been moved 
away from each other, the positioning device can then be easily removed 
from its mounting on the female die member so that the positioning device 
then no longer constitutes any impediment to ready access between the male 
die member and the female die member of the embossing tool, for a 
substrate which is to be embossed thereby. 
In a preferred feature of the invention the housing element is of a 
sleeve-like configuration and in an outside peripheral surface thereof has 
a groove which extends therearound and in which there is arranged a spring 
ring. The groove and the spring ring are preferably so dimensioned that 
the spring ring projects beyond the outside peripheral surface, with an 
outside peripheral portion. 
As in an embossing tool of that kind the female die member usually 
comprises a suitable metal or a suitable metal alloy such as for example 
brass, it is preferable for the spring ring to comprise a spring metal and 
to be in the form of an open O-ring. Spring rings of that kind are 
desirably commercially available standard components which are available 
at inexpensive cost. By virtue of the housing element of the positioning 
device according to the invention having a spring ring of spring metal in 
the form of an open O-ring, the positioning device can be reliably fixed 
in an associated hole for mounting it in the female die member. The 
positioning device according to the invention can also be removed again 
from the mounting hole in the die member with a specific and controlled 
movement and without involving a great deal of time and complication if, 
at its end portion which is towards the male die member, the housing 
element is provided with an annular flange having an undercut 
configuration. In that case the annular flange firstly serves for 
providing for accurately defined spacing of the male die member which is 
arranged in accurately positioned relationship with respect to the female 
die member, and then the undercut configuration that the annular flange 
desirably includes serves in particular to permit the positioning device 
to be engaged for example by the gripping claws of a gripping tool and 
thus removed therewith from its mounting hole in the female die member. 
The gripping tool may be any suitable gripping tool which can perform that 
removal operation and may be for example a tool which is similar to a 
suitably modified insulation-stripping pincer tool as is used for 
stripping insulation from the wires of an installation cable. 
In a preferred feature of the invention the holding element is of a 
piston-like configuration including a holding pin portion which is 
arranged to project out of the housing element, while the spring member 
bears against a terminal closure portion of the housing element, at an end 
thereof remote from the holding pin portion. The terminal closure portion 
may be an annular end portion which is suitably fixed to the sleeve-like 
housing element, for example by peening or the like. 
The holding pin portion preferably has a groove extending around the 
periphery thereof, for accommodating a spring ring. In a preferred 
configuration of that kind the groove and the spring ring are so 
dimensioned that an outside peripheral portion of the spring ring projects 
radially beyond the holding pin portion. The spring ring may preferably 
comprise a rubber material and is in the form of a closed O-ring. Like the 
above-mentioned spring ring of the housing element, this spring ring on 
the holding pin portion is a commercially available, low-cost standard 
component. The spring ring on the holding pin portion advantageously 
comprises a rubber material in particular for the reason that the male die 
member which is temporarily secured in accurately positioned relationship 
with respect to an associated female die member by means of the 
positioning devices according to the invention usually comprises a 
suitable plate-like plastic material. 
It will be noted in this respect that the spring ring of rubber material 
either serves to be clamped or locked in a hole in the male die member or 
to urge the male die member against the annular flange of the housing 
element, if the longitudinal dimension of the holding pin portion is of 
suitable magnitude. At any event the holding pin portion projects beyond 
the male die member which is temporarily held fast to the positioning 
device. When then the combination of the female die member and the male 
die member which is accurately positioned thereon is clamped between the 
appropriate components of an associated embossing tool, the holding pin 
portion is moved back into the housing element and the male die member 
fixed to the associated component of the embossing tool, for example by 
means of adhesive strips or the like. The movement of the holding pin 
portion back into its associated housing element of the positioning device 
simultaneously automatically provides that the male die member is released 
from the positioning device and consequently from the female die member to 
which the positioning device is fixed, for example by being mounted in a 
suitable mounting hole therein. After the two components of the embossing 
tool have been moved away from each other and thus after the male die 
member which is fixed to one component of the embossing tool and the 
female die member which is fixed to the other component thereof have been 
moved away from each other, it is thus easily possible, as already 
mentioned above, to remove the positioning device from the female die 
member, for example by means of a suitable gripping tool, after which 
access for a substrate to be embossed, between the female and male die 
members of the embossing tool, is no longer impeded by the presence of 
positioning devices. 
It will be noted at this point that a substrate to be embossed may be any 
suitable substrate such as a paper substrate or a combination of a paper 
substrate with an embossing foil. In the last-mentioned case it may be 
desirable for the matrix to be adapted to be heatable. 
Further objects, features and advantages of the invention will be apparent 
from the following description of a preferred embodiment of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring to the drawing shown therein is a portion of an embossing tool 
comprising a female die member 10 having therein a hole 12 in which a 
positioning device as generally indicated at 14 can be temporarily fixed. 
The positioning device 14 has a sleeve-like housing element 16 and a 
holding element 18 which is disposed in the housing element 16 and which 
is axially displaceable therein, in a piston-like manner, The holding 
element 18 serves for temporarily fixing a male die member 20 of which a 
portion is shown, in relation to the female die member 10. The male die 
member 20 has a hole 22 for receiving a portion of the holding element 18, 
as will be described hereinafter. It will be seen therefore that the 
holding element 18 is axially displaceable with respect to the housing 
element 16 between a first position of projecting into the hole 22 in the 
male die member 20 to hold the male die member 20 fast with respect to the 
female die member 10, and a second position in which it is retracted into 
the housing element 16 and thus releases the male die member. 
At its end portion 24 which is towards the male die member 20 the 
sleeve-like housing element 16 has an annular flange 26 which, along its 
outside periphery 28, has a portion of an undercut configuration as 
indicated at 30. 
At its inside the annular flange 26 has a central bore 32, the diameter of 
which is smaller than the inside diameter of the sleeve portion indicated 
at 34 of the housing element 16. The sleeve portion 34 is accommodated in 
the hole 12 in the female die member 10. In that way, formed between the 
central bore 32 in the annular flange 26 and the sleeve portion 34 is an 
annular step 36 which forms an abutment or limiting means for the holding 
element 18. The FIGURE shows the holding element 18 in its position of 
butting against the step 36 and thus in its position of projecting to its 
maximum extent out of the housing element 16. 
At its outside peripheral surface 38 the housing element 16 has a groove 40 
which extends around the periphery thereof and which is disposed at the 
end portion 42, which is remote from the annular flange 26, of the housing 
element 16 or more specifically the sleeve portion 34 thereof. The 
peripherally extending groove 40 serves to receive a spring ring 44 which 
may be an open O-ring comprising a suitable material such as a spring 
metal. The groove 40 and the spring ring 44 are so dimensioned that the 
spring ring 44 has an outside peripheral portion 46 thereof projecting 
beyond the outside peripheral surface 38 of the housing element 16, and 
presses resiliently radially outwardly against the cylindrical inside wall 
surface of the hole 12 in the female die member 10 and thereby temporarily 
retains the positioning device 14 in the hole 12 in the female die member 
10. 
The end portion 42 of the housing element 16 is formed with a central 
enlarged portion 48 which serves for fixing a terminal closure portion 50 
therein. The terminal closure portion 50 is in the form of an annular end 
portion and is fixedly connected to the housing element 16, by any 
suitable means such as glueing, soldering, welding, peening or the like. 
Disposed between the terminal closure portion 50 and the piston-like 
holding element 18, in the interior of the sleeve-like housing element 16, 
is a spring member 52 shown in the form of a compression coil spring. The 
spring member 52 urges the holding element 18 into the position shown in 
the FIGURE, in which the male die member 20 is reliably held fast to the 
female die member 10 in accurately positioned relationship by the holding 
element 18. 
The holding element 18 has a holding pin portion 54 of an outside diameter 
which, with sliding fit tolerance, is matched to the central bore 32 in 
the annular flange 26 of the housing element 16. At its free end part, the 
holding pin portion 54 has a peripherally extending groove 56 in which a 
spring ring 58 is accommodated. The groove 56 and the spring ring 58 are 
so dimensioned that the spring ring 58 projects radially with an outside 
peripheral portion 60 beyond the holding pin portion 54. The spring ring 
58 is preferably in the form of a closed O-ring comprising a suitable 
material such as rubber. The spring ring 58 serves for temporarily 
reliably fixing the male die member 20 to the positioning device 14 and 
thus the female die member 10. 
When the male die member 20 is accurately suitably positioned and fixed to 
the female die member 10 by means of the positioning device 14, the 
combination of the female die member 10 and the male die member 20 is 
arranged between the two components (not shown) of an embossing tool and 
those two components are moved towards each other. In that procedure, in a 
first working step, the respective holding pin portion 54 is urged into 
the associated housing element 16, while at the same time the 
corresponding spring member 52 is mechanically stressed. In that retracted 
position of the holding element 18, at the same time the male die member 
20 is released from the positioning device 14. Simultaneously the male die 
member 20 is fixed to the associated component of the embossing tool, for 
example by means of suitable adhesive elements such as adhesive strips. 
The two components of the embossing tool can then be moved away from each 
other again. When that happens the spring member 52 of the respective 
positioning device 14 is mechanically relieved of stress again, that is to 
say the holding element 18 moves from the retracted position of releasing 
the male die member 20 into the active position of extending out of the 
housing element 16. The positioning device 14 can then be removed from the 
hole 12 in the female die member 10 by means of a suitable gripping tool 
as referred to above so that thereafter there is no positioning device 14 
that could impede access to the embossing space between the female die 
member 10 and the male die member 20. 
It will be noted in the above-described operating procedure that the spring 
ring 58 of rubber material serves to become clamped in the hole in the 
male die member 20 or to urge the male die member 20 against the annular 
flange 26 on the housing element 16, if the holding pin portion 54 is of a 
suitable longitudinal dimension. At any event the holding pin portion 54 
projects beyond the male die member 20 when temporarily retained to the 
positioning device 14. When the assembly of the male and female die 
members is then clamped between the two movable components of the 
embossing tool, the holding pin portion 54 is moved back into the housing 
element 16 and the male die member 20 is suitably fixed to the associated 
component of the embossing tool. The movement of the holding pin portion 
54 back into the housing element 16 means that the male die member is at 
the same time automatically released from the positioning device 14 and 
thus the female die member 10. After the male and female die members have 
then been moved away from each other, it is readily possible for the 
positioning device 14 to be removed from the die member on which it is 
mounted. 
It will be seen therefore that the invention provides a positioning device 
which can be readily fitted to and removed from its operative position in 
relation to the embossing tool on which it is to be used, with the 
provision of a holding element which is displaceable between a position of 
holding a workpiece to be stamped fast and a retracted position of 
releasing the workpiece, in relation to the housing element of the 
positioning device. 
It will be noted that the above-described embodiment of the invention has 
been set forth solely by way of example and illustration of the principles 
of the invention and that various modifications and alterations may be 
made therein without thereby departing from the spirit and scope of the 
invention.