[0001] The invention concerns a locking device for securing a tool in a machine such as,
for example, a bending machine, a pressing machine or the like, where the tool, e.g.
a bending tool, a press tool or the like, is secured in a tool holder in the machine.
The tool has a shaft part which is accommodated in a tool-receiving channel in the
tool holder and is secured herein partly by means of a safety arrangement which co-operates
with a keyway in the tool holder and partly by means of a locking system.
[0002] A locking device of this kind is known from EP patent publication no. 494 714, where
the locking device is used to secure a press tool in a power press, where an upper
press tool and a lower press tool can move towards each other for the processing of
a material which is placed between the two press tools. With this known apparatus,
the locking device can be used for securing both the upper and the lower press tool.
[0003] The known locking device comprises both a safety arrangement and a locking system.
The safety arrangement secures the press tool immediately upon this being placed in
the tool holder, after which the locking system which, e.g., can be of a mechanical,
pneumatic, electrical or hydraulic type, can be activated so that the press tool is
clamped in the tool holder. The system works in a corresponding manner when the press
tool is to be removed, in that the locking system is first deactivated so that the
press tool is secured solely by the safety arrangement. Hereafter, the safety arrangement
can be released manually so that the press tool can be taken out.
[0004] An advantage with this known arrangement is thus that the press tool can be inserted
manually in a relatively simple manner and possibly moved manually until the correct
position is found, after which the actual securing of the tool is effected by means
of the locking system. The same applies when the press tool is to be removed, in that
the clamping is first released by means of the locking system, after which the press
tool is released manually by means of the safety device.
[0005] The known safety device consists of a spring-loaded pawl which can be displaced in
a hole transversely to the shaft part of the tool, a release button which can similarly
be displaced in a hole transversely to the tool, and a connecting link which can transfer
the movement from the release button to the spring-loaded pawl. When the shaft part
of the tool is inserted into the tool holder, the spring-loaded pawl can engage in
the keyway in the tool holder so that the tool is secured. When the tool is to be
removed, the release button, which is disposed in an intermediate part of the tool,
can be pressed in, in that the connecting link hereby transfers the movement to the
spring-loaded pawl which is thus released from its engagement with the keyway.
[0006] Consequently, with this known technique use is made of a relatively large number
of individual parts for the safety arrangement, the result being that relatively great
friction arises in this when it is activated. The safety arrangement can thus be difficult
to release, especially when this involves an upper tool which after deactivation of
the locking device is secured solely by the safety arrangement, and which thus in
practice hangs in the pawl or the pawls. Since the pawl or pawls must be displaced
linearly in order for the engagement with the keyway to be released, there will be
quite great friction between the pawls and the keyway over the whole movement of the
pawl or the pawls. However, this friction can be reduced if the user lifts up the
tool at the same time, but this can place quite a strain on the user, in that use
is often made of tools which are of a considerable weight.
[0007] With the known technique, use is made of a locking system which similarly employs
parts which move linearly for the clamping of the tool, in that a number of pins are
provided which can be moved forwards and backwards in the holes in a locking system,
in that in their displaced-forward position they are pressed in against the tool which
is thus secured. In practice, with the use of this known system there will be certain
limitations with regard to the use of tools, in that tools of a length which is less
than the distance between two pins in the locking system can not be placed at any
random position in the tool holder, but must be placed in a position in which it can
be secured by a locking pin.
[0008] An object of the present invention is to provide a locking device with a locking
system and a safety device which is relatively simple in construction and which is
easier to operate than the known system.
[0009] This is achieved in that the safety device comprises a hook which is suspended in
a pivotal manner in an intermediate part of the tool, said hook having a latch part
which can engage in the keyway when the shaft part of the tool is mounted in the tool
holder.
[0010] It is hereby achieved that use is made solely of a single movable element, i.e. the
hook, whereby the friction between fixed and moving parts in the arrangement is considerably
reduced. At the same time, since the hook describes a turning movement, it is achieved
that the latch part of the hook will be lifted free of the keyway in the tool holder
immediately after the initiation of the turning movement, so that there will no longer
be any friction in relation to the keyway when the user merely holds the tool at the
same height. In order to reduce the friction in the safety device, it is thus not
necessary, as is the case with the known arrangement, to effect a straining lift upwards.
Therefore, the safety device will be easier to release than with the known technique.
[0011] With an expedient embodiment, such as disclosed in claim 2, the axis of rotation
for the hook is placed in such a manner that the friction which exists between the
latch part of the hook and the keyway is more or less equalised by the horizontal
force which, due to the pull of gravity on the tool, will seek to draw the latch part
free of the keyway. It is hereby achieved that a slight influence will be sufficient
to release the securing of the tool by the hook.
[0012] With a further embodiment, as disclosed in claim 3, the one end of the hook is configured
as a release arm, and the axis of rotation for the hook is disposed between the release
arm and the latch part. The release arm ca be influenced by the intermediate part
of the tool, e.g. by a part of the release arm extending out through the recess in
the tool's intermediate part, or in that a part of the release arm can be influenced
through the recess, e.g. by means of a tool. Finally, the end of the release arm can
lie more or less flush with the intermediate piece but, however, it must be positioned
so that the user can influence the release arm with a finger. The safety device can
thus be released by pressing the release arm in against the tool, whereby the latch
part will be moved out of engagement with the keyway and into the shaft part of the
tool.
[0013] Alternatively, the locking device can be configured as disclosed in claim 4, in that
the release arm is disposed between the axis of rotation for the hook and its latch
part, e.g. by being configured as an operating button or the like. This operating
button will thus be able to be operated, i.e. pressed in, from the front of the tool,
i.e. that side through which the latch part of the hook projects. With this embodiment,
it is thus possible to form the recess in the tool in which the hook is disposed exclusively
from the front of the tool. Also with this embodiment, the release arm can be configured
so that it projects out from the intermediate part and can be operated directly, or
it can be configured so that it lies flush with or under the surface of the intermediate
part so that it can be operated by the user pressing a finger or possibly a tool into
a cavity or an opening.
[0014] As disclosed in claim 5, it can be expedient for the hook to be connected with a
spring which will ensure that the latch part of the hook extends out through the recess
in the shaft part when the release arm is not influenced. Moreover, this spring will
exercise that force which must be overcome to release the hook when the locking device
is configured as disclosed in claim 2. By suitable dimensioning, it is thus possible
to closely determine that force which is necessary to release the hook.
[0015] In accordance with another expedient embodiment which is characterised in claim 6,
a recess for the hook can comprise a part which serves as a stop for the turning movement
of the hook, so that the latch part can not be moved too far outside the shaft part.
[0016] If the hook is further configured as disclosed in claim 7, whereby the latch part
of the hook has an inclined surface, it is achieved that the tool can be inserted
directly in the tool holder, in that due to the inclined surface the latch part upon
being inserted will be pushed into the shaft part and slide into engagement with the
keyway at the correct position.
[0017] As disclosed in claim 8, it can be expedient for the tool to be provided with a longitudinal
locking groove in which a locking hook of a locking plate can enter into engagement
and thus establish the clamping of the tool.
[0018] As disclosed in claim 9, the locking plate can be arranged so that it can tilt. around
a pivot point, so that the locking hook which is disposed on the lower part will engage
with the locking groove when the upper part of the locking plate is influenced by
an activating element, which can be a highly-flexible hose. With this hose, a turning
movement of the locking plate is achieved in a simple manner. The flexible hose will
influence the locking plate uniformly over its length and, when the pressure is removed
from the hose, very little force is required to induce the locking plate to move back
in the open position. The use of hydraulic cylinders and the like is hereby avoided,
which among other things can be an advantage in cases where it is desired to avoid
any form of oil escape, in that the flexible hose can be activated with e.g. compressed
air or a liquid which is not contaminating. Moreover, with this embodiment it will
be an advantage that use can be made of tools of any random smaller length, and that
these tools can be placed in a random position in relation to the length of the locking
plate.
[0019] Furthermore, as disclosed in claim 10, a return spring can be disposed in connection
with the locking plate, so that when the activation element is deactivated, the locking
plate is drawn out of its engagement with the locking groove, whereby the clamping
of the tool is released.
[0020] In cases where the securing of longer tools in the tool holder is required, it can
be expedient as disclosed in claim 11 to provide the tool with two or more uniformly
disposed hooks, so that the tool is safely secured until the clamping is effected
with the locking system.
[0021] Finally, as disclosed in claim 12, keyways can be configured in both sides of that
channel in the tool holder which accommodates the shaft part of the tool. It is hereby
achieved that a choice can be made between two different positions of the tool (turned
180° in relation to each other), which is of special significance when the tool is
not symmetrical in relation to a centreline for the tool holder.
[0022] In the following, the invention will be explained in more detail with reference to
the drawing, where
- fig. 1
- shows a cross-section of a tool holder and a bending tool which are secured to each
other by means of a locking device according to the invention,
- fig. 2
- is a perspective view of a bending tool with a hook configured according to the invention,
which is disposed in a recess in the bending tool,
- fig. 3
- is a perspective view of a locking plate for use in connection with the locking device,
- fig. 4
- shows an alternative embodiment of a hook, similarly shown in perspective,
- fig. 5
- shows the forces which influence the latch part of the hook when this is used in an
upper tool which is suspended in a tool holder,
- fig. 6
- shows a cross-section corresponding to fig. 1, but with an alternative embodiment
of a hook and a bending tool, and
- fig. 7
- shows a cross-section corresponding to fig. 1, but where there is also illustrated
a securing of the locking plate to the tool holder.
[0023] In fig. 1 there is seen a cross-section of a tool holder 1 in which a tool is mounted
by means of the invention. In the example shown, the tool is a bending tool 5. The
shown tool with tool holder form part of a not-shown machine as an elongated part
which, for example, under a certain pressure can be moved downwards towards an underlying
counter-part which can either be mounted in a fixed manner or possibly be moved upwards.
The underlying counter-part can, for example, consist of a tool holder mounted with
a tool corresponding to that shown in fig. 1, but turned 180° so that the tool faces
upwards. The two tools, which are thus secured in each their tool holder 1, can be
identical, but can naturally also be different, all depending on the actual use of
the machine. For example, such a machine can be used for the forming of material under
pressure, especially sheet material, in that the machine can e.g. be a power press
or a bending machine as shown in fig. 1.
[0024] The tool holder shown in fig. 1 has a longitudinal channel or groove 2 which is used
to accommodate the tool 5, a side part of said longitudinal channel being configured
with a keyway 3 which, as will be described later, is used to secure the tool 5. In
the shown example, the keyway 3 is shown as a channel with a rectangular cross-section,
but the keyway can be configured with any other suitable shape.
[0025] The tool 5 consists of a shaft part 6, an intermediate part 7 and a foot part 8.
The foot part of the tool is determinative for the function of the tool, and in the
shown example is configured as a bending blade which can be used, for example, for
the bending of sheet metal material, but it will be obvious that the tool can be configured
with foot parts suitable for any form of pressing, bending, shearing, blanking operations
and the like. The shaft part 6 of the tool is configured in such a manner that it
can be inserted with a good fit in the tool-receiving channel 2 in the tool holder
1. As is shown on fig. 2, which shows a tool 5 in perspective, the shaft part has
a top surface 6a which abuts up against the bottom of the tool-receiving channel 2
or is possibly at a distance from this bottom, and a first side surface 6b and a second
side surface 6c which lie up against the sides in the tool-receiving channel 2. Moreover,
in connection with the shaft part there is an auxiliary support surface 6d which abuts
up against an underside of the tool holder. As shown in fig. 2, an undercut 6e is
provided between this auxiliary support surface 6d and the first side surface 6b of
the shaft part. This undercut is provided for reasons of production, in that it can
otherwise be difficult to produce the two adjoining surfaces 6b and 6d so that a perfect
inside angle of 90° is formed. With the shown configuration, the two surfaces 6b and
6d are able to be brought in tight contact with the corresponding right-angled part
of the tool holder, such as shown in fig. 1. Providing that the top surface 6a can
abut against the bottom of the tool-receiving channel 2, the auxiliary support surface
6d can possibly be omitted.
[0026] In the shaft part 6 and in the intermediate part 7 of the tool there is provided
a recess 9 which is configured substantially as a slot which extends parallel with
the plane of the drawing in fig. 1. In the shaft part of the tool, this recess opens
out in the second side surface 6c, and on the opposite side of the tool the recess
opens out in the intermediate part 7. in this recess there is mounted a hook 12 which
at its one end is configured as a latch part 14, and at its other end is configured
with a release arm 15. The hook is also provided with a hole 13 which is used for
suspending the hook in the recess 9, in that a pivot pin or axle is led through this
hole 13 and is suspended on each side of the recess 9.
[0027] In the tool 5 there is also provided a spring 16 which influences the hook 12 so
that the latch part 14 will be pressed into the keyway 3 when the tool is inserted
into the tool holder. As shown in fig. 1, this spring 16 can be a helical spring which
is retained with its one end in a blind hole in the tool, and which with its other
end influences the release arm 15. Finally, in the shaft part 6 of the tool there
is provided a stop 10 for the hook, this stop being configured in the second side
surface 6c immediately under the latch part 14, but which can be placed in other suitable
ways. This stop 10 functions as an end stop for the rotating movement of the hook,
and thus prevents the latch part 14 from moving too far out of the shaft part 6.
[0028] The locking device also comprises a locking system which comprises a locking plate
20 which extends along the tool holder 1 as shown in fig. 1. This locking plate 20
is mounted on the tool holder 1 in such a manner that it can tilt or rotate around
a pivot point 21, such as indicated in fig. 1. The lower part 24 of the locking plate
has a locking hook 25 which can grip in under the tool holder 1 and in a locking notch
11 in the tool 5, which locking notch 11 is shown in fig. 2. At the top, the locking
plate 20 stands in connection with an activation element 26 which can move the uppermost
part of the locking plate in relation to the tool holder 1, so that the locking hook
25 can be pressed into the locking notch 11. As shown, this activation element can,
for example, consist of a tubular element 26 which is placed in a recess 4 in the
tool holder. This tubular element, which is of a highly flexible type, is placed between
the tool holder 1 and the locking plate 23 in such a manner that in the inactivated
state it is pressed more or less flat, so that when influenced pneumatically or hydraulically
it expands in circumference and presses the upper part 23 of the locking plate away
from the tool holder. Conversely, when the air or hydraulic pressure is removed from
the tube, it is compressed again, which is effected by means of a return spring 27
which, for example, can be a leaf spring which is placed in a recess or a notch in
the tool holder 1 between this and the lower part 24 of the locking plate. As the
activation element, use can be made, for example, of a tube of the type which is normally
used as e.g. a fire hose.
[0029] As mentioned, in fig. 2 is shown the position of the locking notch 11 on the tool
5, in that the locking notch is shown configured with sloping side surfaces which
correspond to the shape of the locking hook 25 on the locking plate. Fig. 2 also shows
the positioning of the hook 12 in the manner in which this is mounted in the recess
9. It is also shown that immediately below the latch part 14 of the hook and in connection
with the recess 9 there is configured a recess 9a which extends in the longitudinal
direction of the tool 5. In this recess, an element can be inserted which can constitute
the stop 10 for the hook 12. Finally, it is shown that the hook 12 is provided with
a locking notch 17 which allows the locking hook 25 of the locking plate to engage
with the locking notch 11 without influencing the hook 12, such as this is also seen
in fig. 1.
[0030] In fig. 3 the locking plate 20 is shown in perspective, and it is seen that holes
22 are provided between the upper part 23 and the lower part 24. In the shown example,
two holes are provided. These holes are used in the suspension of the locking plate,
so that this can tilt around the pivot point 21, which is marked in fig. 7.
[0031] Fig. 4 shows an alternative embodiment for the hook 12, this embodiment distinguishing
itself from that shown in figs. 1 and 2 simply by the latch part 14 being configured
as a strip-like part with a breadth which is considerably greater than the breadth
of the hook 12. With this embodiment, there is thus achieved a better grip in the
keyway 3. However, from the point of view of production technique, this embodiment
requires a more complicated configuration of the recess in the tool 5. Furthermore,
with this embodiment a better control of the hook in the keyway 3 is achieved when
a suspended tool is displaced sideways, e.g. in order to position the tool in the
correct place in the machine. With this embodiment, it can not so easily occur that
the hook tilts over in the keyway and possibly get stuck. Alternatively, special provision
must be made to control sideways movements of the hook, e.g. by configuring the recess
9 in such a way that it serves as a guide for the hook, for example by having a breadth
at certain places which corresponds precisely to the breadth of the hook, or by the
hook being precisely controlled by the pivot pin or axle with which the hook is suspended,
possibly in combination with the configuration of the recess 9.
[0032] In fig. 5 are illustrated those forces which work on the hook 12 and especially the
latch part 14 when the hook secures a tool in an upper tool holder. The pivot axis
for the hook is thus indicated at the point 13, and the engagement point for the latch
part 14 in the keyway 3 is indicated at point 14'. The point of engagement 14' can,
for example, consist of the outermost edge of the keyway 3 adjacent to the tool-receiving
channel 2 or of the point of the latch part, providing that it is this which first
and foremost has contact with the keyway 3. At the pivot point 13, the hook will be
influenced by the force of gravity F
g on the tool. This force will similarly work vertically downwards at the point 14',
but since the point of engagement 14' is not lying vertically over the point 13, there
will be a force F on the latch part which from the point of engagement 14' is directed
towards the pivot point 13. As shown, this force can be divided into two components
at right-angles to each other, i.e. F
g which works vertically downwards and F
gv which works horizontally. The horizontal distance between the pivot point 13 and
the point of engagement 14' is indicated with the letter a, and it is seen that the
greater the distance a, the greater will be the force F and herewith F
gv. The point of engagement 14' is also influenced by a frictional force F
µ ,which in magnitude is equal to F
g times the statistical coefficient of friction µ
0, and which works in the direction opposite to F
gv.
[0033] The frictional force F
µ will thus be independent on the distance a, while the oppositely-directed force F
gv will increase with the distance a. When F
gv is greater than F
µ, the latch part of the hook will be moved out of the keyway 3 without further influence
from outside. Therefore, the distance a can be dimensioned so that it is less than
or equal to that distance where F
gv is equal to F
µ. When F
gv and F
µ are equal, no force or only insignificant force is required on the hook to bring
this out of its engagement with the keyway 3. The spring 16 will thus also serve to
determine that influence which is required to induce the hook to turn out of engagement,
for a suitably comfortable level for the user, and also, especially when the two above-mentioned
forces F
gv and F
µ are approximately the same, to ensure that the hook is not unintentionally brought
out of engagement by an insignificant force. The advantage with the arrangement is
that the manual force which must be applied in order to release a hook in practice
is the same, regardless of the spatial orientation or physical weight of the tool.
[0034] In fig. 6 is shown a cross-section of a bending tool and a tool holder corresponding
to fig. 1, but with an alternative configuration of the hook and the bending tool.
Individual parts which are configured in the same way as shown in fig. 1 are indicated
with the same reference numbers as in fig. 1, and therefore they will not be discussed
in more detail here. The hook, which is indicated by 12', differs from that which
is shown in fig. 1, in that here the release arm 15' is not configured as a part which
extends from the axis of rotation 13 towards the opposite end of the hook in relation
to the latch part 14, but on the contrary extends mainly in the same direction as
that end of the hook where the latch part 14 is disposed. The significance of this
is that when being released, the release arm 15' can be suitably influenced from the
front, in that it can thus be pushed in towards the intermediate part 7 of the tool.
The spring 16 will thus also be placed differently, in that as shown in fig. 6 it
can be placed in a blind hole immediately behind the release arm 15'. The release
arm can be configured as a separate part which is rigidly connected to the remaining
parts of the hook, but can relatively simply be configured as a part of the hook's
connection part between the axis of rotation 13 and the latch part 14, in that this
merely involves the placing of some form of operating button on the front of the hook,
such as shown in fig. 6.
[0035] A further advantage of this embodiment is that the recess 9 in the tool, in which
the hook 12' is disposed, can be configured exclusively from the front of the intermediate
part 7 and shaft part 6 of the tool, unlike the configuration in fig. 1, where machining
must normally also be carried out from the rear of the tool.
[0036] In connection with the mounting of the hooks 12 or 12' in a tool, it must be mentioned
that the hooks can be placed in the end pieces of a tool, in that the provision of
a recess can thus be effected solely from the end of the tool. When a hook is placed
in such a recess 9, the hook can be secured by a separate component which is fastened
to the tool and prevents the hook from falling out. This can thus involve a plate
which wholly or partly covers the recess 9 in the end piece of the tool.
[0037] The suspension of the locking plate 20 on the tool holder 1 is illustrated in fig.
7, which corresponds to fig. 1 but where the section is taken at a place where a securing
element for the locking plate is provided. Reference numbers are shown only for the
most important of the elements already discussed, i.e. the tool holder 1, the tool
5, the hook 12, the stop 10 and the spring 16 for the hook, the locking plate 20,
the hole 22 in the locking plate and the activation element 26.
[0038] A bolt 30 through the hole 22 in the locking plate is secured in the tool holder
1, in that the bolt is surrounded by a bush 31. As shown, the hole 22 is configured
with two diameters, i.e. partly an inner diameter and partly an outer diameter which
is greater than the inner. In that area of the hole 22 where this has an outer greater
diameter, the bush 31 has an annular recess 32. Between the head of the bolt 30 and
the bush 31 there is provided a tension washer 33 which at the same time secures an
outer slide piece 34 and an inner slide piece 35 against the annular part of the hole
22 between the larger and the smaller diameter. The outer 34 and the inner slide piece
35 are configured with co-operating surfaces which are configured with a cross-section
in the form of part of a circular arc, so that the two slide pieces can be moved in
relation to one another. The locking plate 20 can thus describe the turning movement
in that the inner slide piece 35, which turns together with the locking plate 20,
during its movement can move into the annular recess 32 in the bush 31.
[0039] When a tool 5 is to be mounted in the tool holder 1, the tool is manually placed
opposite the tool-receiving channel 2, and the shaft part 6 is introduced into the
channel. When the inclined surface on the latch 14 makes contact with the locking
hook 25 on the locking plate 20 and/or the lower edge of the tool holder, the hook
12 or 12' will be turned against the spring pressure from the spring 16 so that the
latch part 14 will be pushed into the shaft part of the tool. As will be seen in fig.
1, the locking hook 25 on the locking plate 20 is also provided with an inclined surface,
which will further facilitate this movement.
[0040] When the shaft part 6 of the tool has been pushed so far into the channel 2 that
the under part of the latch part 14 is opposite the lowermost edge of the keyway 3,
the latch part 14 will be pushed into the keyway 3 by the spring 16, so that the tool
5 is now secured in the tool holder. When in this position, the tool can be displaced
in the longitudinal direction of the tool holder until the desired position is found,
in that the latch part 14 can be displaced in the longitudinal direction of the keyway.
When the tool is in the desired position, the activation element 26 is activated so
that the lower part 24 of the locking plate 20 is turned in towards the tool and the
locking hook 25 is pressed into the locking notch 11. The locking hook 25 and the
locking notch 11 can be configured so that the tool is pressed into the tool holder
1 in such a manner that the auxiliary support surface 6d and/or the top surface 6a
of the shaft part 6 is pressed against the corresponding parts of the tool holder
1. At the same time, the first side surface 6b of the shaft part will be pressed against
the corresponding side surface in the tool-receiving channel 2, so that the position
of the tool is precisely determined in relation to the tool holder.
[0041] When the tool 5 is to be removed from the tool holder 1, the activation element 26
is deactivated, whereby the locking plate 20 will be turned by the return spring 27
so that the locking hook 25 is moved out of its engagement with the locking notch
11. Hereafter, the tool is held in the tool holder only by the engagement of the latch
20 with the keyway 3, which is of special significance when the tool holder is one
which has downwards-facing channel 2 for receiving the tool, in that here the force
of gravity will naturally seek to draw the tool out of the channel. The tool 5 can
hereafter be handled manually, in that pressing on the release arm 15 or 15' will
release the engagement of the latch part 14 from the keyway 3, so that the shaft part
6 of the tool can be led out of the channel 2.
[0042] As mentioned, the disclosed locking device comprising the locking system and the
safety arrangement can be used both for a tool holder with a downwards-facing channel
2 and a tool holder with an upwards-facing channel 2. Moreover, one or more tools
can be accommodated in a channel 2, in that the tools can be inserted in the tool
holder in extension of one another. In a tool 5 there can be configured one or more
recesses 9 with associated hooks 12 or 12'. However, if a tool is to be inserted and
removed without difficulty by only one person, it is expedient that at the most there
are two hooks per tool.
[0043] The locking plate 20 can be of such a length that it corresponds to the whole length
of the tool holder 1, in that the advantage achieved hereby is that a tool of a smaller
length than the whole of the tool holder can be inserted, secured and locked at any
random place along the tool holder. Use can be made, however, of locking plates of
a smaller length, and such locking plates of a smaller length can be brought together
singly to form a desired length.
[0044] It must also be mentioned that use can be made of other types of locking systems
in connection with the safety arrangement than the kind described above which use
a pivotal locking plate. The safety arrangement disclosed can thus also be used in
connection with locking systems which use linearly-displaceable locking cylinders
and the like for the locking of a tool when this is secured by means of the safety
arrangement.
[0045] Finally, the tool-receiving channel 2 in the tool holder can have a keyway 3 in both
ends of the channel, so that the tool can be inserted in two different positions.
With such a configuration, a locking notch 11 must similarly be configured on each
side of the tool for the securing of the tool by means of the locking plate 20.
1. Locking device for securing a tool in a machine such as, for example, a bending machine,
a pressing machine or the like, where the tool (5), e.g. a bending tool, a press tool
or the like, is secured in a tool holder (1) in the machine, in that the tool (5)
has a shaft part (6) which is accommodated in a tool-receiving channel (2) in the
tool holder (1) and is secured herein partly by means of a safety arrangement which
co-operates with a keyway (3) in the tool holder (1), and partly by means of a locking
system, characterized in that the safety arrangement comprises a hook (12, 12') which is pivotally mounted in an
intermediate part (7) of the tool (5), said hook (12) having a latch part (14) which
can engage in the keyway (3) when the shaft part (6) of the tool (5) is mounted in
the tool holder (1).
2. Locking device according to claim 1, characterized in that the friction in the safety arrangement is wholly or partly equalised by placing the
pivot axis (13) for the hook (12) in the tool at such a horizontal distance (a: fig.
1 and 5) from the point of engagement (14') of the latch part (14) in the keyway (3)
that a horizontal frictional force (Fµ), which works between the keyway (3) and the latch pan (14), is substantially neutralised
by an oppositely-directed force (Fgv) on the latch part which is brought about by the pull of gravity on the tool.
3. Locking device according to claim 1 or 2, characterized in that the hook (12) is pivotally suspended around a pivot axis (13) which is disposed between
the latch part (14) for the hook and a release arm (15) for the hook, in that the latch part (14) is disposed in the area for an opening out of a recess (9) in
the shaft part (6) of the tool, and in that the release arm (15) is disposed in the intermediate par (7) of the tool.
4. Locking device according to claim 1 or 2, characterized in that a release arm (15') for the hook (12') is disposed in the intermediate part (7) of
the tool between a pivot axis (13) for the hook (12') and the latch part (14) for
the hook, in that the release arm (15') is possibly coincident with a connection link between the hook's
pivot axis (13) and latch part (14).
5. Locking device according to one or more of the claims 1-4, characterized in that the hook (12, 12') is connected with a spring arrangement (16) which influences the
hook with a spring force around the pivot axis (13), so that the latch part (14) is
influenced to move out through the opening-out of the recess in the shaft part (6).
6. Locking device according to one or more of the claims 1-5, characectized in that the
tool (5), in connection with a recess (9) for the hook, comprises a part which functions
as a stop (10) for the hook (12, 12'), so that the movement of the hook is restricted,
especially the movement of the latch part (14) outside the shaft part (6).
7. Locking device according to one or more of the claims 1-6, characterized in that the latch part (14) of the hook has an outer surface which towards the top surface
(6a) of the shaft part slopes inwards towards the shaft part (6).
8. Locking device according to one or more of the claims 1-7, characterized in that the tool is provided with a longitudinal locking notch (11) on the shaft part (6)
or on the intermediate part (7), and that the locking system comprises a locking plate
(20) which is pivotally suspended and has a locking hook (25) which can enter into
engagement with the longitudinal locking notch, so that the tool (5) is locked securely
in the tool holder (1).
9. Locking device according to claim 8, characterized in that the locking plate (20) has a lower part (24) on which the locking hook (25) is configured,
and an upper part (23), in that between the upper part (23) and the lower part (24) there is a pivot point (21) for
the locking plate (20), and in that the upper part (23) can be influenced by an activation element (26), which is in
the form of a flexible hose which extends the whole length of the locking plate, so
that the locking hook (25) is pressed into the tool's longitudinal locking notch (11).
10. Locking device according to claim 8 or 9, characterized in that the locking system comprises a return spring (27), preferably in the form of e.g.
a leaf spring, which is placed between the lower part (24) of the locking plate and
the tool holder (1), in that said return spring (27) can influence the locking plate (20) so that the locking
hook (25) is moved out of the locking notch (11).
11. Locking device according to one or more of the claims 1-10, characterized in that the tool (5) comprises two or more hooks (12) which are of substantially the same
configuration, and which are distributed along the longitudinal direction of the tool.
12. Locking device according to one or more of the claims 1-11, characterized in that the tool-receiving channel (2) contains a keyway (3) in both sides, in that each of said keyways can co-operate independently with the hook (12) or hooks of
the safety arrangement.
1. Arretiervorrichtung zum Befestigen eines Werkzeugs in einer Maschine, wie beispielsweise
einer Biegemaschine, einer Pressmaschine oder dergleichen, wobei das Werkzeug (5),
beispielsweise ein Biegewerkzeug, ein Presswerkzeug oder dergleichen, in einem Werkzeughalter
(1) in der Maschine befestigt ist und das Werkzeug (5) einen Schaftteil (6) aufweist,
der in einer Werkzeugaufnahmenut (2) in dem Werkzeughalter (1) aufgenommen ist und
darin teilweise mittels einer Sicherheitsanordnung, die mit einer Keilnut (3) in dem
Werkzeughalter (1) zusammenwirkt, und teilweise mittels eines Arretiersystems befestigt
ist, dadurch gekennzeichnet, dass die Sicherheitsanordnung einen Haken (12, 12') umfasst, der schwenkbar in einem Mittelteil
(7) des Werkzeugs (5) angebracht ist, wobei der Haken (12) einen Verriegelungsteil
(14) aufweist, der in die Keilnut (3) eingreifen kann, wenn der Schaftteil (6) des
Werkzeugs (5) in dem Werkzeughalter (1) angebracht ist.
2. Arretiervorrichtung nach Anspruch 1, dadurch gekennzeichnet, dass die Reibung in der Sicherheitsanordnung vollständig oder teilweise ausgeglichen wird,
indem die Schwenkachse (13) für den Haken (12) in dem Werkzeug in einem horizontalen
Abstand (a; Fig. 1 und 5) zum Punkt des Eingriffs (14') des Verriegelungsteils (14)
in der Keilnut (3) angeordnet wird, durch den eine horizontale Reibkraft (Fµ), die
zwischen der Keilnut (3) und dem Verriegelungsteil (14) wirkt, im Wesentlichen durch
eine entgegengesetzt gerichtete Kraft (Fgw) auf den Verriegelungsteil neutralisiert wird, die durch den Zug der Schwerkraft
an dem Werkzeug bewirkt wird.
3. Arretiervorrichtung nach Anspruch 1 oder 2, dadurch gekennzeichnet, dass der Haken (12) um eine Schwenkachse (13) herum schwenkbar aufgehängt ist, die zwischen
dem Verriegelungsteil (14) für den Haken und einem Lösearm (15) für den Haken angeordnet
ist, dass der Verriegelungsteil (14) in dem Bereich für eine Öffnung einer Aussparung
(9) in dem Schaftteil (6) des Werkzeugs nach außen angeordnet ist und dass der Lösearm
(15) in dem Mittelteil (7) des Werkzeugs angeordnet ist.
4. Arretiervorrichtung nach Anspruch 1 oder 2, dadurch gekennzeichnet, dass ein Lösearm (15') für den Haken (12') in dem Mittelteil (7) des Werkzeugs zwischen
einer Schwenkachse (13) für den Haken (12') und dem Verriegelungsteil (14) für den
Haken angeordnet ist, und dass der Lösearm (15') möglicherweise mit einem Verbindungsgelenk
zwischen der Schwenkachse (13) und dem Verriegelungsteil (14) des Hakens zusammenfällt.
5. Arretiervorrichtung nach einem der Ansprüche 1-4, dadurch gekennzeichnet, dass der Haken (12, 12') mit einer Federanordnung (16) verbunden ist, die den Haken mit
einer Federkraft um die Schwenkachse (13) herum beeinflusst, so dass der Entriegelungsteil
(14) so beeinflusst wird, dass er sich durch die Öffnung der Aussparung in dem Schaftteil
(6) nach außen hindurch heraus bewegt.
6. Arretiervorrichtung nach einem der mehreren der Ansprüche 1-5, dadurch gekennzeichnet, dass das Werkzeug (5) in Verbindung mit einer Aussparung (9) für den Haken einen Teil
umfasst, der als ein Anschlag (10) für den Haken (12, 12') wirkt, so dass die Bewegung
des Hakens, insbesondere die Bewegung des Verriegelungsteils (14) außerhalb des Schaftteils
(6), eingeschränkt wird.
7. Arretiervorrichtung nach einem oder mehreren der Ansprüche 1-6, dadurch gekennzeichnet, dass der Verriegelungsteil (14) des Hakens eine äußere Fläche aufweist, die in Richtung
der oberen Fläche (6a) des Schaftteils nach innen auf den Schaftteil (6) zu geneigt
ist.
8. Arretiervorrichtung nach einem oder mehreren der Ansprüche 1-7, dadurch gekennzeichnet, dass das Werkzeug mit einer Längs-Arretierkerbe (11) an dem Schaftteil (6) oder an dem
Mittelteil (7) versehen ist und dass das Arretiersystem eine Arretierplatte (20) umfasst,
die schwenkbar aufgehängt ist und einen Arretierhaken (25) aufweist, der in Eingriff
mit der Längs-Arretierkerbe eintreten kann, so dass das Werkzeug (5) sicher in dem
Werkzeughalter (1) arretiert ist.
9. Arretiervorrichtung nach Anspruch 8, dadurch gekennzeichnet, dass die Arretierplatte (20) einen unteren Teil (24), an dem der Arretierhaken (25) ausgebildet
ist, sowie einen oberen Teil (23) aufweist, dadurch, dass zwischen dem oberen Teil
(23) und dem unteren Teil (24) ein Schwenkpunkt (21) für die Arretierplatte (20) ist
und dadurch, dass der obere Teil (23) durch ein Aktivierungselement (26) beeinflusst
werden kann, das die Form eines flexiblen Schlauchs hat, der sich über die gesamte
Länge der Arretierplatte erstreckt, so dass der Arretierhaken (25) in die Längs-Arretierkerbe
(11) des Werkzeugs gedrückt wird.
10. Arretiervorrichtung nach Anspruch 8 oder 9, dadurch gekennzeichnet, dass das Arretiersystem eine Rückstellfeder (27), vorzugsweise in Form beispielsweise
einer Blattfeder, umfasst, die zwischen dem unteren Teil (24) der Arretierplatte und
dem Werkzeughalter (1) angeordnet ist, und dadurch, dass die Rückstellfeder (27) die
Arretierplatte (20) so beeinflussen kann, dass der Arretierhaken (25) aus der Arretierkerbe
(11) herausbewegt wird.
11. Arretiervorrichtung nach einem oder mehreren der Ansprüche 1-10, dadurch gekennzeichnet, dass das Werkzeug (5) zwei oder mehr Haken (12) umfasst, die im Wesentlichen den gleichen
Aufbau haben und die in der Längsrichtung des Werkzeugs verteilt sind.
12. Arretiervorrichtung nach einem oder mehreren der Ansprüche 1-11, dadurch gekennzeichnet, dass die Werkzeugaufnahmenut (12) eine Keilnut (3) an beiden Seiten enthält und dadurch,
dass jede der Keilnuten unabhängig mit dem Haken (12) oder den Haken der Sicherheitsanordnung
zusammenwirken kann.
1. Dispositif de verrouillage apte à fixer un outil dans une machine telle que, par exemple,
une machine à plier, une machine à presser ou de même, où l'outil (5), par exemple
un outil de pliage, un outil de presse ou de même, est fixé dans un support outil
(1) dans la machine, en ce que l'outil (5) a une partie en manche (6) qui est reçue
dans un canal de réception d'outil (2) dans le support outil (1) et est fixé dedans
partiellement au moyen d'un dispositif de sécurité qui coopère avec une rainure de
clavette (3) dans le support outil (1), et partiellement au moyen d'un système de
verrouillage, caractérisé en ce que le dispositif de sécurité comprend un crochet (12, 12') qui est monté de manière
rotative sur une partie intermédiaire de l'outil (5), ledit crochet (12) ayant une
partie en loquet (14) qui s'engage dans la rainure de clavette (3) quand la partie
en manche (6) de l'outil (5) est montée dans le support outil (1).
2. Dispositif de verrouillage selon la revendication 1, caractérisé en ce que la friction dans le dispositif de sécurité est totalement ou partiellement égalisé
en plaçant l'axe pivot (13) pour le crochet (12) dans l'outil à une distance horizontale
telle (a: fig 1 et 5) du point d'engagement (14') de la partie en loquet (14), dans
la rainure de clavette (3) qu'une force de friction horizontale (Fµ) qui agit entre la rainure de clavette (3) et la partie en loquet (14) est sensiblement
neutralisée par une force dirigée de manière opposée (Fgv) sur la partie en loquet qui est apportée par l'attraction de la gravité sur l'outil.
3. Dispositif de verrouillage selon la revendication 1 ou 2, caractérisé en ce que le crochet (12) est suspendu de manière rotative autour d'un axe pivot (13) qui est
situé entre la partie en loquet (14) pour le crochet et un bras de relâchement (15)
pour le crochet, en ce que la partie en loquet (14) est disposée entre la zone pour une ouverture hors d'un
évidement (9) dans la partie en manche (6) de l'outil et en ce que le bras de relâchement (15) est disposé dans la partie intermédiaire (7) de l'outil.
4. Dispositif de verrouillage selon la revendication 1 ou 2, caractérisé en ce qu'un bras de relâchement (15') pour le crochet (12') est situé dans la partie intermédiaire
(7) de l'outil entre un axe pivot (13) pour le crochet (12') et la partie en loquet
(14) pour le crochet, en ce que le bras de relâchement (15') est éventuellement identique à une liaison de connexion
entre l'axe de pivot du crochet (13) et la partie en loquet (14).
5. Dispositif de verrouillage selon l'une ou plusieurs des revendications 1 à 4, caractérisé en ce que le crochet (12, 12') est connecté à un dispositif de ressort (16) qui agit sur le
crochet avec une force ressort autour de l'axe pivot (13), de manière à ce que la
partie en loquet (14) a tendance à se déplacer à travers l'ouverture en dehors de
l'évidement de la partie en manche (6).
6. Dispositif de verrouillage selon l'une ou plusieurs des revendications 1 à 5, caractérisé en ce que l'outil (5), en connexion avec un évidement (9) pour le crochet, comprend une partie
qui agit comme un butoir (10) pour le crochet (12, 12'), de manière à ce que le mouvement
du crochet est restreint, spécialement le mouvement de la partie en loquet (14) en
dehors de la partie en manche (6).
7. Dispositif de verrouillage selon l'une ou plusieurs des revendications 1 à 6, caractérisé en ce que la partie en loquet (14) du crochet a une surface extérieure qui, en direction de
la surface supérieure (6a) de la partie en manche, penche vers l'intérieur en direction
de la partie en manche (6).
8. Dispositif de verrouillage selon l'une ou plusieurs des revendications 1 à 7, caractérisé en ce que l'outil est prévu avec une encoche de verrouillage longitudinale (11) sur la partie
en manche (6) ou sur la partie intermédiaire (7), et en ce que le système de verrouillage comprend une plaque de verrouillage (20) qui est suspendue
de manière pivotante et a un crochet de verrouillage (25) qui peut entrer en s'engageant
dans l'encoche de verrouillage longitudinale, de manière à ce que l'outil (5) soit
verrouillé solidement dans le support de l'outil (1).
9. Dispositif de verrouillage selon la revendication 8, caractérisé en ce que la plaque de verrouillage (20) a une partie inférieure (24) sur laquelle le crochet
de verrouillage (25) est disposé, et une partie supérieure (23), en ce qu'entre la partie supérieure (23) et la partie inférieure (24), il y a un point de pivot
(21) pour la plaque de verrouillage (20), et en ce que la partie supérieure (23) peut être influencée par un élément d'activation (26),
qui est sous la forme d'un tuyau flexible qui s'étend tout le long de la plaque de
verrouillage, de manière à ce que le crochet de verrouillage (25) soit comprimé dans
l'encoche de verrouillage longitudinale (11) de l'outil.
10. Dispositif de verrouillage selon la revendication 8 ou 9, caractérisé en ce que le système de verrouillage comprend un ressort de rappel (27), préférentiellement
sous la forme, par exemple d'un ressort à lames, qui est placé entre la partie inférieure
(24) de la plaque de verrouillage et le support outil (1), en ce que ledit ressort de rappel (27) peut influencer la plaque de verrouillage (20) de manière
à ce que le crochet de verrouillage (25) soit déplacé hors de l'encoche de verrouillage
(11).
11. Dispositif de verrouillage selon l'une ou plusieurs des revendications 1 à 10, caractérisé en ce que l'outil (5) comprend deux ou plus crochets (12) qui sont sensiblement de la même
configuration, et qui sont distribués le long de la direction longitudinale de l'outil.
12. Dispositif de verrouillage selon l'une ou plusieurs des revendications 1 à 11, caractérisé en ce que le canal de réception d'outil (2) contient une rainure de clavette (3) sur les deux
côtés, en ce que chacune desdits rainures de clavette peut coopérer de manière indépendante avec le
ou les crochets (12) du dispositif de sécurité.