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EP 0 983 840 B1 |
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EUROPEAN PATENT SPECIFICATION |
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Mention of the grant of the patent: |
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13.10.2004 Bulletin 2004/42 |
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Date of filing: 27.08.1999 |
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Press with cam drive
Presse mit Nockenantrieb
Presse avec entraînement à came
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Designated Contracting States: |
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AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE |
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Priority: |
05.09.1998 GB 9819301
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Date of publication of application: |
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08.03.2000 Bulletin 2000/10 |
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Proprietor: McKechnie UK Limited |
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Walsall,
West Midlands WS9 8DS (GB) |
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Inventor: |
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- Ketteringham, Roger Harry
Halesowen,
West Midlands B62 0AY (GB)
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Representative: Barnfather, Karl Jon, Dr. et al |
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Withers & Rogers,
Goldings House,
2 Hays Lane London SE1 2HW London SE1 2HW (GB) |
(56) |
References cited: :
WO-A-81/01871 DE-A- 19 642 204 GB-A- 2 046 393
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DD-A- 217 176 FR-A- 2 519 581 US-A- 4 924 693
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Note: Within nine months from the publication of the mention of the grant of the European
patent, any person may give notice to the European Patent Office of opposition to
the European patent
granted. Notice of opposition shall be filed in a written reasoned statement. It shall
not be deemed to
have been filed until the opposition fee has been paid. (Art. 99(1) European Patent
Convention).
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[0001] Invention relates to a press and in particular, but not exclusively, a press for
installing bush type fasteners into substrates such as aperture sheet material for
example for use in fastening components of an article along an assembly line. One
of said presses is disclosed in WO 81 01871 A.
[0002] It is known to provide hydraulic presses comprising an oil reservoir, pump and hydraulic
ram as well as various control devices which effect control of the movement of a pressing
tool carried by the ram in order to locate and/or install a fastener in a substrate
at an operable pressing location on the pressing machine.
[0003] However, such hydraulic presses suffer from various drawbacks including the requirement
for a large storage tank for hydraulic fluids such as oil, slow speed of operation
due to the build up of pressure before releasing the hydraulic ram, excessive noise,
a large stroke or length of travel of the tool which has inherent safety problems,
and difficulties in repair and maintenance. Also, hydraulic presses suffer from the
drawback that the pressing tool is virtually under its full maximum load throughout
its entire stroke which again provides inherent safety problems.
[0004] The present invention seeks to provide a press which overcomes or at least mitigates
one if not more of the above problems or other problems of the prior art. According
to one aspect of the invention there is provided a press for installing bush type
fasteners into substrates such as aperture sheet material, comprising a cam follower
operable to drive a pressing device such as a tool towards an operable pressing location,
and a driven cam having a cam surface for effecting movement of the cam follower and
a recess for receiving the cam follower within the cam. The recess is preferably located
between the leading and tailing edge of the cam surface and/or provides no camming
action of its own.
[0005] Beneficially therefore the length or travel or stroke of the cam follower and hence
tool under load from the driven cam is minimised to the eccentricity of the cam surface
whilst the cam allows greater travel of the cam follower without exerting the load
thereon by enabling the cam follower to be received in the recess.
[0006] Preferably means are provided for enabling gravity location of the pressing device
at a position proximal the operable pressing location and/or tool position wherein
the cam follower is substantially removed from the recess in the cam. Beneficially
therefore the load on the tool is substantially equal to the weight of the tool and
connected components such as cam follower which is considerably less than the load
which might be exerted on the tool during a fastener installation operation which
might be in the order of 4 to 8 tonnes for example.
[0007] Preferably, the gravity location means comprises co-operating components associated
with the cam follower and cam respectively, such as slider and slider guide. Preferably
the length of the recess is in the order of the diameter of the cam follower or greater.
Preferably, the recess is in the order of 2 or more times the diameter of the cam
follower.
[0008] Preferably the length of the recess is sufficient to enable alignment of the axis
of rotation of the cam follower and the axis of rotation of the driven cam beneficially
therefore to provide that if the cam is driven when the cam follower is in this stowed
position, it does not effect movement of the cam follower and hence does not effect
movement of the tool.
[0009] Preferably, the eccentricity of the cam surface is less than 5 millimetres and more
preferably in the order of less than 2 millimetres. Beneficially therefore the stroke
of the tool under operable load is less than the thickness of a finger. Preferably
the cam is a rising cam with maximum eccentricity achieved at greater than 180° of
rotation and preferably at about 270° of rotation.
[0010] Preferably a position sensor is provided in operable communication with a controller
thereby to ensure that the cam follower is substantially removed from the recess before
actuation of the driven cam can commence. Preferably two position sensors are provided
and the controller conducts a logic test to ensure that both sensors detect substantial
removal of the cam follower from the recess within a predetermined time period before
actuation of the driven cam plate can take place. Preferably the sensors are located
adjacent to one another and/or preferably at substantially the same axial position
with respect to the axis of travel of the cam follower. Preferably the pre-determined
time is less than half a second and more preferably in the order of 100 milliseconds
or less. In a preferred form, the predetermined time is in the order of 50 milliseconds.
[0011] Preferably the controller is programmed with a logic sequence such that actuation
of the driven cam only occurs if sensors 1 and 2 detect movement of the cam follower
substantially out of the recess within a pre-determined time of one another thereby
to effect a switch such as a change of state of a monostable device, and power to
the driven cam only continues as long both sensors are closed and the switch or monostable
is in its activated state. Preferably, as soon as one of the sensors opens power to
the driven cam is removed and the switch or monostable is reset.
[0012] Preferably means are provided to enable alignment of the cam recess in a desired
position such as vertical thereby to enable gravity feed of the cam follower and pressing
tool to a lower, operable position. Preferably the location means comprises a lobed
annulus fixedly attached to the drive shaft to the cam, and a sensor for detecting
the position of the lobe about the circumference of the annulus. The sensor can be
an induction sensor for example and the lobe can be metallic radial protrusion from
the annulus. Preferably two lobes are provided substantially adjacent to one another
and separated by a recess. Preferably, the recess is relatively narrow and/or the
annulus is located on the shaft so as to indicate the top dead centre position of
the cam, or other preferred location for the removal of the cam follower from the
recess, when the sensor detects the recess between the lobes. Preferably the recess
is in the order 10° of the circumference wide. Preferably the lobe or lobes is/are
in the order of 25 degrees of the circumference in width.
[0013] Preferably means is provided to reposition the cam follower in the recess. The means
can be a ram such as a pneumatic ram.
[0014] Another aspect of the invention provides a fastener installing machine comprising
one or more of the features of the press discussed above.
[0015] Another aspect of the invention provides a cam having a recess for receiving a cam
follower.
[0016] An embodiment of the invention will now be described, by way of example only, with
the reference to the accompanying drawings, in which:
Figure 1 is a schematic perspective view of part of the press according to the invention;
Figures 2 and 3 are side and front elevation views respectively of the press shown
in Figure 1 in a stowed position;
Figures 4 and 5 are side and front elevation views respectively of the press shown
in Fig 1 when the cam follower is in a lowered operable position;
Figures 6 and 7 are front and side elevation views of the driven cam;
Figures 8, 9 and 10 are schematic front elevation views of the relative positions
of the cam follower and cam at different stages in the operation of the press;
Figures 11 and 12 schematic front and side elevation views respectively of a location
mechanism forming part of the press according to the invention; and
Figure 13 is a schematic block diagram of components forming part of the press according
to the invention.
[0017] Referring to Figures 1 to 5 there is shown a press 10 according to the invention
comprising a driven cam 12 and a cam follower 14. Cam follower 14 is rotatably journalled
in a bearing 16 which is attached to slider plate or plunger 18. Slider plate 18 is
received in a recess or guide forming part of a slider housing 20 which forms part
of the main body of the press 10.
[0018] Slider plate 18 comprises means for attaching press tool thereto, and referring generally
to Figure 1 it can be seen that the press 10 operates to enable sliding motion of
tool 22 up and down (in the orientation shown) when cam 12 rotates to effect vertical
movement of follower 14 and hence tool 22 thereby to effect pressing action on a fasteners
(not shown) at an operable pressing location (also not shown) of the press 10.
[0019] Referring to Figures 2 to 5, it can be seen that in more detail press 10 comprises
driven cam 12 which is attached to a drive shaft 30 which in turn is driven by a motor.
Shaft 30 is journalled in a housing 32 which is connected to guide housing 20 thereby
forming the main body of press 10 fixedly attached to the shaft 30 is a lobed annulus
34 above which is positioned a sensor 36. Referring to Figure 11 and 12 it can be
seen that lobed annulus 34 comprises a pair of lobes 35 and 37 separated by a recess
38. In a preferred form, the circumferential length of lobes 35 and 37 in the order
of 25 degrees and the length of recess 38 is in the order of 10 degrees. Accordingly,
circumferential length between the leading and trailing edges of lobes 35 and 37 is
in the order of 300 degrees.
[0020] Referring again to Figures 1 to 5, it can be seen that press 10 further comprises
position sensors 24 and 26 for detecting a shoulder 48 forming part of bearing 16.
The positional sensors 24 and 26 can for example be optical or inductive sensors.
In a preferred form, the sensors are positioned at substantially the same axial position
with respect to the axis of movement of follower 14 along its vertical path. A ram
46 such as a pneumatic ram is provided which is attached at one end to the body and
at the other end to bearing 16. Ram 46 effects lifting of bearing 16 and cam follower
14 after a stroke. There is further provided a chuck or other receiving device 44
connected to slider plate 18, for receiving a tool 22.
[0021] Referring to Figures 6 and 7, it can be seen that cam 12 comprises a channelled recess
50 having a width slightly greater than the diameter of cam follower 14 and a length
of approximately twice the diameter of cam follower 14 but wherein the curved end
of the recess 50 is approximately the radius of cam follower 14 beyond the centre
of rotation at bore 52. Further bores 54 are provided for locating the cam onto the
end of drive shaft 30, for example using threaded bolts. Cam 12 further comprises
a cam surface 56 which extends from the radiused ends of channel 50 through approximately
300 degrees of the circumference of cam 12. Preferably, the cam surface is provided
on the periphery of cam 12. The eccentricity of the cam surface 56 is preferably rising
in an anti-clockwise direction. Preferably the maximum extent, or most eccentric region,
of cam surface 56 is substantially at 90 degrees to axis A (or 270° to the start position).
The cam surface 56 can go through a local minimum at the upper edge along axis A shown
in Figure 6.
[0022] Referring now to Figure 13, the schematic diagram shows a controller 60 at the heart
of the control system for operating the press. Controller 60 can be a mini controller,
microprocessor or other programmable device. User controls are provided such as an
on button 62, reset button 64, manual button 66, automatic button 68, and actuator
button 70. Also shown is a motor 72 for driving cam 12 via shaft 30 on instructions
from controller 60. Preferably, motor 72 is a three phase motor which can be driven
using a three phase inverter taking supply from single phase mains electricity for
example. The use of such a three phase motor enables controller 60 to control the
speed, acceleration and deceleration, direction and stopping point of the motor and
hence cam 12. Controller 60 is further operably in communication with sensor 30 for
determining the orientation of cam 12 and with position sensors 24 and 26 for determining
the location of cam follower 14. Controller 60 further operably activates a valve
74 allowing actuation of pneumatic ram 46 from a pressurised gas supply 76.
[0023] Figures 8, 9 and 10 show the relative orientation of cam 12 and follower 14 throughout
the operation of the press as now described.
[0024] In its rest or stowed position, cam follower 14 is located substantially in axial
alignment with drive shaft 30 and is held in position through the action of pneumatic
ram 46. The position of cam 12 shown in Figures 2 and 3 is the top dead centre position
and is determined by controller 60 using sensor 36 which locates recess 38 between
lobes 35 and 37. When turned on through actuation of buttons 62 and in manual mode
through actuation of button 66, compression of actuation button 70 closes valve 74
and pneumatic ram 46 acts as a simple pneumatic damper allowing cam following 14 to
move downwardly out of recess 50 in cam 12 under the weight of the cam follower 14,
bearing 16, slider plate 18 and tool 22 for example.
[0025] Controller 60 interrogates sensors 24 and 26 to determine if they detect shoulder
48 of bearing 16 as it falls downwardly. If sensors 24 and 26 detect the shoulder
within a predetermined time limit, such as less than 0.1 of a second and the sensors
remain closed (or otherwise indicate the presence of shoulder 48 in a lowered position)
then controller 62 actuates motor 72 effecting rotation of cam 12 in either a clockwise
direction. Accordingly, by setting the length of tool 22 and other components accordingly,
it is possible for tool 22 to be proximal the fastener as cam surface 56 engages cam
follower 14 when the cam 12 begins to rotate. Of course, in the embodiment shown where
the cam rises anti-clockwise, the cam is driven clockwise but of course the opposite
orientation of the cam is possible and hence it is also possible to drive the cam
in an anti-clockwise direction. Indeed, beneficially both directions of movement of
the motor are possible to enable re-setting of the system. Preferably also, in a manual
mode it is possible for an operator manually to move the cam forward and backwards
(anti-clockwise or clockwise) for ease of setting.
[0026] Movement of cam 12 through 360 degrees effects a vertical movement of cam follower
14 and hence tool 22 through the extent of eccentricity of the cam. When or just before
the top dead centre position is again detected by sensor 36 and controller 60, power
is removed from shaft 30 by de-activating motor 72 and valve 74, having been opened
at any stage after engagement of follower 14 with cam surface 56 during the rotation
of the cam, effects movement of cam follower 14 back into recess 50 thereby clearing
tool 22 away from the operable pressing location of the press. Preferably, controller
60 reduces the power of motor 72 at the beginning and end of the rotation of cam 12.
This can be achieved by causing shaft 30 to rotate at a slower speed when sensor 36
detects either of lobes 36 or 37.
[0027] When operated in this manual mode, the operator positions the substrate and fastener
beneath the tool and then presses the actuation button 70 to recommence the release
of follower 14 from recess 50 and so on. If an automatic fastener feeding mechanism
is used the automatic mode button 68 can actuated and the operation controlled by
controller 60 having means for ensuring the fastener is located beneath the tool before
commencing the pressing cycle. Of course this mode can be run without an automatic
feeder also.
1. A press (10) for installing bush type fasteners into substrates such as apertured
sheet material, comprising a cam follower (14) operable to drive a pressing device
such as a tool (22) towards an operable pressing location, and a driven cam (12) having
a cam surface (56) for effecting movement of the cam follower (14) and a recess (50)
for receiving the cam follower (14) within the cam (12), characterised in that the cam surface (56) is on the outer periphery of the cam (12), the recess (50) is
located on the cam surface (56) and extends radially towards the center point of the
cam and in that when the cam follower (14) is in its rest or stowed position the cam follower is
stationary in the recess (50).
2. A press according to Claim 1 wherein the recess is located between the leading and
trailing edge of the cam surface, and preferably wherein the recess does not provide
a camming action of its own.
3. A press according to Claim 1 or 2 wherein the stroke of the cam follower is approximately
the extent of eccentricity of the cam surface.
4. A press according to any of Claims 1 to 3 comprising means for enabling location of
the pressing device due to gravity at a position proximal one of the operable pressing
location and the tool position wherein the cam follower is substantially removed from
the recess in the cam, and preferably the load on the tool is substantially equal
to the weight of the tool and connected components such as cam follower prior to a
fastener installation operation, and/or wherein the gravity location means comprises
co-operating components associated with the cam follower and cam respectively, and/or
wherein the gravity location means comprises a slider and slider guide.
5. A press according to any preceding claim wherein the length of the recess is in the
order of the diameter of the cam follower.
6. A press according to any of Claims 1 to 4 wherein the length of the recess is greater
than the diameter of the cam follower, and preferably the length of the recess is
in the order of two or more times the diameter of the cam follower.
7. A press according to any preceding claim wherein the length of the recess is sufficient
to enable a stowed position in which substantial alignment of the axis of rotation
of the cam follower and the axis of rotation of the driven cam is provided such that
when the cam is driven and the cam follower is in the stowed position, the cam does
not effect sufficient movement of the cam follower to effect movement of the tool.
8. A press according to any preceding claim wherein the eccentricity of the cam surface
is less than 5 millimetres, and preferably the eccentricity of the cam surface is
in the order of less than 2 millimetres.
9. A press according to any preceding claim wherein the cam is a rising cam with maximum
eccentricity achieved at more than 180° of rotation, and preferably wherein maximum
eccentricity is achieved at about 270° of rotation.
10. A press according to any preceding claim comprising a position sensor operably in
communication with a controller operable to ensure that the cam follower is substantially
removed from the recess before actuation of the driven cam can commence, and preferably
comprising two position sensors and the controller conducts a logic test to ensure
that both sensors detect substantial removal of the cam follower from the recess within
a predetermined time period before actuation of the driven cam plate can take place,
and/or more preferably wherein the sensors are located adjacent to one another, and/or
preferably still wherein the sensors are located at substantially the same axial position
with respect to the axis of travel of the cam follower.
11. A press according to Claim 10 wherein the predetermined time is less than half a second,
and preferably wherein the predetermined time is in the order of 11 milliseconds or
less, and more preferably wherein the predetermined time is in the order of 50 milliseconds.
12. A press according to Claim 10 or 11 wherein the controller is programmed with a logic
sequence such that actuation of the driven cam only occurs if the first and second
sensors detect movement of the cam follower substantially out of the recess within
a predetermined time of one another thereby to effect a switch such as a change of
a monostable device, and power to the driven cam only continues as long as both sensors
are closed and the switch or monostable is in its activated state, and preferably
wherein as soon as one of the sensors opens, power to the driven cam is removed and
the switch or monostable is reset.
13. A press according to any preceding claim comprising means to enable alignment of the
cam recess in a desired position, such as inverted vertical, thereby to enable gravity
feed of the cam follower and pressing tool to a lower, operable position, and preferably
the alignment means comprises a lobed annulus fixedly attached to the drive shaft
to the cam, and a sensor for detecting the position of the lobe about the circumference
of the annulus, and/or preferably the sensor comprises an induction sensor and the
lobe comprises a metallic radial protrusion from the annulus.
14. A press according to Claim 13 wherein two lobes are provided substantially adjacent
to one another and separated by a recess, and preferably the recess is relatively
narrow, and/or preferably the recess is in the order 10° of the circumference wide.
15. A press according to Claim 14 wherein the annulus is located on the shaft so as to
indicate the top dead centre position of the cam, or other preferred location for
the removal of the cam follower from the recess, when the sensor detects the recess
between the lobes.
16. A press according to any of Claims 13, 14 or 15 wherein the lobe or lobes is/are in
the order of 25 degrees of the circumference in width.
17. A press according to any preceding claim comprising means provided to position the
cam follower in the recess like a ram such as a pneumatic ram.
18. A fastener installing machine comprising a press according to any preceding claim.
1. Presse (10) zum Einbringen von buchsenartigen Verbindungselementen in Substrate wie
beispielsweise ein Lochplattenmaterial, mit einem Nockenstößel (14) zum Antreiben
einer Pressvorrichtung wie beispielsweise eines Werkzeugs (22) zu einer Betriebspressstellung,
und einem getriebenen Nocken (12) mit einer Nockenfläche (56) zum Bewirken einer Bewegung
des Nockenstößels (14) und einer Ausnehmung (50) zum Aufnehmen des Nockenstößels (14)
in dem Nocken (12),
dadurch gekennzeichnet,
dass die Nockenfläche (56) an dem Außenumfang des Nockens (12) ist, die Ausnehmung (50)
an der Nockenfläche (56) positioniert ist und sich radial zu dem Mittelpunkt des Nockens
erstreckt, und, wenn der Nockenstößel (14) in seiner Ruhe- oder Stauposition ist,
der Nockenstößel in der Ausnehmung (50) unverschiebbar ist.
2. Presse nach Anspruch 1, bei welcher die Ausnehmung zwischen der Vorder- und der Hinterkante
der Nockenfläche positioniert ist, und die Ausnehmung bevorzugt selbst keine Nockenwirkung
vorsieht.
3. Presse nach Anspruch 1 oder 2, bei welcher der Hub des Nockenstößels etwa das Exzentrizitätsmaß
der Nockenfläche ist.
4. Presse nach einem der Ansprüche 1 bis 3, mit einer Einrichtung zum Ermöglichen einer
Positionierung der Pressvorrichtung durch Schwerkraft an einer Position nahe einer
der Betriebspressstellung und der Werkzeugposition, wobei der Nockenstößel im Wesentlichen
aus der Ausnehmung in dem Nocken entfernt wird, und die Belastung auf das Werkzeug
vor einem Einbringvorgang eines Befestigungselements bevorzugt im Wesentlichen gleich
dem Gewicht des Werkzeugs und verbundener Komponenten wie beispielsweise dem Nockenstößel
ist, und/oder die Schwerkraftpositioniereinrichtung zu dem Nockenstößel bzw. dem Nocken
gehörende zusammenwirkende Komponenten aufweist, und/oder die Schwerkraftpositioniereinrichtung
einen Schieber und eine Schieberführung aufweist.
5. Presse nach einem der vorhergehenden Ansprüche, bei welcher die Länge der Ausnehmung
in der Größenordnung des Durchmessers des Nockenstößels liegt.
6. Presse nach einem der Ansprüche 1 bis 4, bei welcher die Länge der Ausnehmung größer
als der Durchmesser des Nockenstößels ist, und die Länge der Ausnehmung bevorzugt
in der Größenordnung des Zwei- oder Mehrfachen des Durchmessers des Nockenstößels
liegt.
7. Presse nach einem der vorhergehenden Ansprüche, bei welcher die Länge der Ausnehmung
ausreichend ist, um eine Stauposition zu ermöglichen, in welcher eine wesentliche
Ausrichtung der Drehachse des Nockenstößels und der Drehachse des getriebenen Nockens
vorgesehen ist, sodass, wenn der Nocken angetrieben wird und sich der Nockenstößel
in der Stauposition befindet, der Nocken keine ausreichende Bewegung des Nockenstößels
bewirkt, um eine Bewegung des Werkzeugs zu bewirken.
8. Presse nach einem der vorhergehenden Ansprüche, bei welcher die Exzentrizität der
Nockenfläche geringer als 5 mm ist, und die Exzentrizität der Nockenfläche bevorzugt
in der Größenordnung von weniger als 2 mm liegt.
9. Presse nach einem der vorhergehenden Ansprüche, bei welcher der Nocken ein Steignocken
mit einer bei einer Drehung von mehr als 180° erreichten maximalen Exzentrizität ist,
und bei welcher die maximale Exzentrizität bevorzugt bei einer Drehung von etwa 270°
erreicht wird.
10. Presse nach einem der vorhergehenden Ansprüche, mit einem Positionssensor, der mit
einer Steuerung zum Gewährleisten, dass der Nockenstößel im Wesentlichen aus der Ausnehmung
entfernt wird, bevor eine Betätigung des getriebenen Nockens starten kann, in Verbindung
steht, und bevorzugt mit zwei Positionssensoren, wobei die Steuerung einen Logiktest
durchführt, um zu gewährleisten, dass beide Sensoren ein wesentliches Entfernen des
Nockenstößels aus der Ausnehmung in einer vorbestimmten Zeitdauer erfassen, bevor
eine Betätigung der getriebenen Nockenplatte stattfinden kann, und/oder bevorzugter
die Sensoren zueinander benachbart positioniert sind, und/oder noch bevorzugter die
Sensoren an im Wesentlichen der gleichen Achsenposition bezüglich der Bewegungsachse
des Nockenstößels angeordnet sind.
11. Presse nach Anspruch 10, bei welcher die vorbestimmte Zeit weniger als eine halbe
Sekunde beträgt, und die vorbestimmte Zeit bevorzugt in der Größenordnung von 100
ms oder weniger liegt, und die vorbestimmte Zeit bevorzugter in der Größenordnung
von 50 ms liegt.
12. Presse nach Anspruch 10 oder 11, bei welcher die Steuerung mit einer solchen Logikfolge
programmiert ist, dass eine Betätigung des betriebenen Nockens nur stattfindet, falls
der erste und der zweite Sensor eine Bewegung des Nockenstößels im Wesentlichen aus
der Ausnehmung in einer vorbestimmten Zeit voneinander erfassen, um dadurch eine Schaltung
wie beispielsweise eine Änderung einer monostabilen Vorrichtung zu bewirken, und die
Energie zu dem getriebenen Nocken nur andauert, solange beide Sensoren geschlossen
sind und sich der Schalter oder die monostabile Vorrichtung in ihrem aktivierten Zustand
befindet, und bei welcher bevorzugt die Energie zu dem getriebenen Nocken entfernt
wird und der Schalter oder die monostabile Vorrichtung zurückgesetzt wird, sobald
einer der Sensoren öffnet.
13. Presse nach einem der vorhergehenden Ansprüche, mit einer Einrichtung zum Ausrichten
der Nockenausnehmung in einer gewünschten Position, wie beispielsweise kopfüber, um
dadurch einen Schwerkraftsvorschub des Nockenstößels und ein Pressen des Werkzeugs
in eine untere Betriebsstellung zu ermöglichen, wobei die Ausrichtungseinrichtung
bevorzugt einen gelappten Kreisring, der an der Antriebswelle des Nockens fest angebracht
ist, und einen Sensor zum Erfassen der Position des Lappens um den Umfang des Kreisrings
aufweist, und/oder bevorzugt der Sensor einen Induktionssensor aufweist und der Lappen
einen radialen Metallvorsprung von dem Kreisring aufweist.
14. Presse nach Anspruch 13, bei welcher zwei Lappen im Wesentlichen benachbart zueinander
und durch eine Ausnehmung beabstandet vorgesehen sind, und die Ausnehmung bevorzugt
relativ eng ist und/oder die Ausnehmung bevorzugt in der Größenordnung von 10° der
Umfangsweite ist.
15. Presse nach Anspruch 14, bei welcher der Kreisring so auf der Welle angeordnet ist,
dass er die obere mittlere Totpunktstellung des Nockens oder eine andere bevorzugte
Stellung zum Entfernen des Nockenstößels aus der Ausnehmung anzeigt, wenn der Sensor
die Ausnehmung zwischen den Lappen erfasst.
16. Presse nach einem der Ansprüche 13, 14 oder 15, bei welcher der oder die Lappen in
der Größenordnung von 25° des Weitenumfangs ist/sind.
17. Presse nach einem der vorhergehenden Ansprüche, mit einer Einrichtung zum Positionieren
des Nockenstößels in der Ausnehmung, wie einen Kolben, wie beispielsweise einen Druckluftkolben.
18. Befestigungselement-Einbringmaschine mit einer Presse nach einem der vorhergehenden
Ansprüche.
1. Presse (10) destinée à installer des attaches de type douille dans des supports tels
que des matériaux en feuille à trous, comprenant un galet de came (14) fonctionnant
pour entraîner un dispositif de compression tel qu'un outil (22) vers un emplacement
de compression fonctionnel, et une came entraînée (12) ayant une surface de came (56)
destinée à effectuer le mouvement du galet de came (14) et un évidement (50) destiné
à recevoir le galet de came (14) à l'intérieur de la came (12), caractérisée en ce que la surface de came (56) se trouve sur la périphérie extérieure de la came (12), en ce que l'évidement (50) est situé sur la surface de came (56) et s'étend radialement vers
la pointe de centrage de la came et en ce que lorsque le galet de came (14) est à l'arrêt ou en position rentrée le galet de came
est immobile dans l'évidement (50).
2. Presse selon la revendication 1 dans laquelle l'évidement est situé entre les bords
avant et arrière de la surface de came, et de préférence dans laquelle l'évidement
ne prévoit pas une action de la came qui lui est propre.
3. Presse selon la revendication 1 ou 2 dans laquelle la course du galet de came correspond
approximativement à l'étendue de l'excentricité de la surface de came.
4. Presse selon l'une quelconque des revendications 1 à 3 comprenant des moyens pour
permettre de placer le dispositif de compression en raison de la gravité dans une
position proche de l'un des emplacements de compression fonctionnels et de la position
de l'outil dans laquelle le galet de came est sensiblement retiré de l'évidement dans
la came, et de préférence dans laquelle la charge sur l'outil est sensiblement égale
au poids de l'outil et des composants reliés tels que le galet de came avant l'opération
d'installation d'une attache, et/ou dans laquelle les moyens d'emplacement par gravité
comprennent des composants en interaction associés au galet de came et à la came respectivement,
et/ou dans laquelle les moyens d'emplacement par gravité comprennent une pièce coulissante
et une glissière.
5. Presse selon l'une des revendications précédentes dans laquelle la longueur de l'évidement
est de l'ordre du diamètre du galet de came.
6. Presse selon l'une quelconque des revendications 1 à 4 dans laquelle la longueur de
l'évidement est supérieure au diamètre du galet de came, et de préférence dans laquelle
la longueur de l'évidement est de l'ordre de deux fois le diamètre du galet de came
ou plus.
7. Presse selon l'une quelconque des revendications précédentes dans laquelle la longueur
de l'évidement est suffisante pour permettre une position rentrée dans laquelle l'alignement
sensible de l'axe de rotation du galet de came et de l'axe de rotation de la came
entraînée est prévu de sorte que lorsque la came est entraînée et que le galet de
came est en position rentrée, la came n'effectue pas un mouvement du galet de came
suffisant pour effectuer le mouvement de l'outil.
8. Presse selon l'une quelconque des revendications précédentes dans laquelle l'excentricité
de la surface de came est inférieure à 5 millimètres, et de préférence dans laquelle
l'excentricité de la surface de came est de l'ordre de moins de 2 millimètres.
9. Presse selon l'une quelconque des revendications précédentes dans laquelle la came
est une came d'arrêt ayant une excentricité maximum obtenue en effectuant une rotation
de plus de 180°, et de préférence dans laquelle l'excentricité maximum est obtenue
en effectuant une rotation d'environ 270°.
10. Presse selon l'une quelconque des revendications précédentes comprenant un capteur
de position fonctionnellement en communication avec un dispositif de commande fonctionnant
pour assurer que le galet de came est sensiblement retiré de l'évidement avant la
mise en action de la came entraînée, et de préférence comprenant deux capteurs de
position et dans laquelle le dispositif de commande effectue un test logique pour
assurer que les deux capteurs détectent le déplacement sensible du galet de came à
partir de l'évidement dans une période de temps donnée avant que la mise en action
du plateau-came entraîné puisse avoir lieu, et/ou plus préférablement dans laquelle
les capteurs sont situés adjacents l'un par rapport à l'autre, et/ou de préférence
encore dans laquelle les capteurs sont situés sensiblement dans la même position axiale
par rapport à l'axe de course du galet de came.
11. Presse selon la revendication 10 dans laquelle le temps donné est inférieur à une
demi-seconde, et de préférence dans laquelle le temps donné est de l'ordre de 11 millisecondes
ou moins, et plus préférablement dans laquelle le temps donné est de l'ordre de 50
millisecondes
12. Presse selon la revendication 10 ou 11 dans laquelle le dispositif de commande est
programmé avec une séquence logique de sorte que la mise en action de la came entraînée
se produise uniquement si les premier et deuxième capteurs détectent le mouvement
du galet de came sensiblement en dehors de l'évidement dans un temps donné l'un par
rapport à l'autre pour effectuer ainsi un aiguillage tel qu'un changement d'un dispositif
monostable, et que la puissance fournie à la came entraînée continue uniquement tant
que les deux capteurs sont fermés et que l'aiguillage ou le monostable est dans son
état activé, et de préférence dans laquelle dès que l'un des capteurs s'ouvre, la
puissance fournie à la came entraînée est retirée et l'aiguillage ou le monostable
est remis à l'état initial.
13. Presse selon l'une quelconque des revendications précédentes comprenant des moyens
pour permettre l'alignement de l'évidement de la came dans une position souhaitée,
telle qu'en position verticale inversée, pour permettre ainsi l'alimentation par gravité
du galet de came et de l'outil de compression dans une position inférieure, fonctionnelle,
et de préférence dans laquelle les moyens d'alignement comprennent une couronne à
lobes fixement attachée à l'arbre d'entraînement de la came, et un capteur destiné
à détecter la position du lobe par rapport à la circonférence de la couronne, et/ou
de préférence dans laquelle le capteur comprend un capteur inductif et le lobe comprend
une protubérance radiale métallique à partir de la couronne.
14. Presse selon la revendication 13 dans laquelle deux lobes sont prévus sensiblement
adjacents l'un par rapport à l'autre et séparés par un évidement, et de préférence
dans laquelle l'évidement est relativement étroit, et/ou de préférence dans laquelle
l'évidement a une largeur de l'ordre de 10° de circonférence.
15. Presse selon la revendication 14 dans laquelle la couronne est située sur l'arbre
afin d'indiquer la position de point mort haut de la came, ou un autre emplacement
préféré pour le retrait du galet de came de l'évidement, lorsque le capteur détecte
l'évidement entre les lobes.
16. Presse selon l'une quelconque des revendications 13, 14 ou 15 dans laquelle le lobe
ou les lobes a/ont une largeur de l'ordre de 25 degrés de circonférence.
17. Presse selon l'une quelconque des revendications précédentes comprenant des moyens
prévus pour positionner le galet de came dans l'évidement comme un piston tel qu'un
piston pneumatique.
18. Machine pour installer des attaches comprenant une presse selon l'une quelconque des
revendications précédentes.