U.S. patent application number 09/093277 was filed with the patent office on 2001-12-06 for method and apparatus for producing a crimp connection.
Invention is credited to EGLI, TONY, EHLERT, HILMAR, MEISSER, CLAUDIO.
Application Number | 20010047674 09/093277 |
Document ID | / |
Family ID | 8230259 |
Filed Date | 2001-12-06 |
United States Patent
Application |
20010047674 |
Kind Code |
A1 |
MEISSER, CLAUDIO ; et
al. |
December 6, 2001 |
METHOD AND APPARATUS FOR PRODUCING A CRIMP CONNECTION
Abstract
A crimping including a stand at which a motor and a transmission
are arranged. Moreover, first guides, at which a crimping bar is
guided, are arranged at the stand. A shaft driven by the
transmission has an eccentric pin at one end, and a resolver for
detection of rotational angle is coupled to the other end. The
crimping bar includes of a slide member guided in the first guides
and of a tool holder with a retaining fork. The slide member stands
in loose connection with the eccentric pin, wherein the rotational
movement of the eccentric pin is converted into a linear movement
of the slide member. The tool holder actuates a tool, which
together with an anvil produces the crimp connection. An operator
terminal is provided as an interface between the operator and the
crimping press. The operator terminal includes a rotary knob and a
keypad for input of operating data and commands into a control. A
display is provided for visualization of data.
Inventors: |
MEISSER, CLAUDIO; (CHAM,
CH) ; EGLI, TONY; (HOCHDORF, CH) ; EHLERT,
HILMAR; (LUZERN, CH) |
Correspondence
Address: |
KLAUS P STOFFEL
COHEN PONTANI LIEBERMAN & PAVANE
551 FIFTH AVENUE
SUITE 1210
NEW YORK
NY
10176
|
Family ID: |
8230259 |
Appl. No.: |
09/093277 |
Filed: |
June 8, 1998 |
Current U.S.
Class: |
72/20.1 |
Current CPC
Class: |
Y10S 72/712 20130101;
Y10T 29/53235 20150115; H01R 43/0488 20130101 |
Class at
Publication: |
72/20.1 |
International
Class: |
B21C 051/00; B21D
055/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 12, 1997 |
EP |
978 10 371.1 |
Claims
We claim:
1. A method for controlling a crimping process which serves for
connecting a contact with a conductor, comprising the steps of:
driving a crimping tool of a crimping press from a start position
into a crimping position and subsequently into an end position; and
selecting the start and end positions of the crimping tool to
permit processing different contacts.
2. A method according to claim 1, including moving the crimping
tool between the start position and the end position in a
rotational movement in which the start and end are separable in
location.
3. A method according to claim 2, including moving the crimping
tool, in a succeeding crimping process, in a direction of rotation
that is opposite to a direction of the rotation for a preceding
crimping process.
4. A method according to claim 1, and further comprising the step
of detecting a respective position of the crimping tool and using
the detected position for controlling the crimping.
5. A method according to claim 1, and further comprising the step
of selecting a single one of a crimping process for checking a
crimp connection, a crimping process with an intermediate stop for
positioning the conductor, and a crimping process with a
preselected stroke.
6. An apparatus for producing a crimp connection, comprising: a
motor-driven crimping tool; and control means for selectably
controlling position and movement of the crimping tool.
7. An apparatus according to claim 6, wherein the crimping tool
includes a drive motor, the control means including a computer
operatively connected to the drive motor so as to control the drive
motor according to selectable prescribing data and in dependence on
a respective position of the crimping tool.
8. An apparatus according to claim 7, wherein the control means
includes a transmitter operatively provided to detect the
respective position of the crimping tool.
9. An apparatus according to claim 7, wherein the control means
includes an inverter operatively connected between the computer and
the drive motor so as to control the drive motor in accordance with
specification data from the computer.
10. An apparatus according to claim 7, and further comprising an
operator terminal in operative communication with the control
means, and having a keyboard and a display for input and
visualization of user and system data, and further having a rotary
knob for selection of the start and end position of the crimping
tool.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The invention relates to a method of and apparatus for
controlling a crimping process which serves for connecting a
contact with a conductor and in which a crimping tool of a crimping
press is driven from a start position into a crimping position and
subsequently into an end position.
[0003] 2. Discussion of the Prior Art
[0004] Contacts are fixed to conductors, which have been previously
stripped of insulation, by means of a crimping press, wherein at
the same time a crush or press connection--also called crimp
connection--is produced between the contact and the conductor
insulation and a crush or press connection is produced between the
contact and the electrically conductive conductor wire. The
crimping press essentially consists of a stand, at which a drive
for a crimping tool is arranged, and a crimping bar, which is
guided and driven at the stand and which actuates the exchangeable
tool for production of the crimp connection. The linear movement,
which is necessary for the crimping process, of the tool is derived
from, for example, a rotational movement which is generated by
means of a motor, a transmission and a shaft, which is driven by
the transmission, with an eccentric pin. Also known are crimping
presses in which the linear movement is generated directly by means
of hydraulic and/or pneumatic linear drives.
[0005] The sizes and shape of the contacts can vary widely
according to the respective use, which makes different tools
necessary. Also, the crimp zones of the contacts are differently
formed. In the case of processing of a contact with an open crimp
zone, the stripped conductor is brought about 5 to 10 millimeters
over the contact and exactly positioned in the axial direction
relative to the contact by means of a sensor. Upon lowering of the
tool with the two crimping dies--a first crimping die for the
insulation crimp and second crimping die for the wire crimp--the
conductor is held by means of a mechanical device and lowered, in
company, by the tool movement, wherein a crimp connection is
produced between the contact and the conductor insulation and a
crimp connection is produced between the contact and the
electrically conductive conductor wire. The processing of a contact
with a closed crimp zone is more costly, because the stripped
conductor has to be guided into a tubular opening of the crimp
zone. The tube of the contact is aligned, by appropriate centering,
during an intermediate stop of the tool, which facilitates the
pushing of the conductor wire into the tube. The processing of
contacts with a closed crimp zone is more time-intensive by
comparison with the processing of contacts with an open crimp
zone.
[0006] The crimp connection arises between the movable first or
second crimping die for the insulation crimp or for the wire crimp
and a correspondingly constructed, fixedly arranged anvil. During
the crimping process, the tool together with the dies is driven
towards the anvil through a specific dimension. Moreover, the
contact is similarly advanced through a contact indexing by means
of the die movement by way of a mechanical system.
[0007] Crimping presses with a tool stroke of 30 millimeters or 40
millimeters are the general standard in conductor processing. The
crimping presses predominantly operate on the eccentric principle,
wherein the linear movement of the die is produced by means of the
eccentric pin arranged on the driven shaft. The rotating eccentric
pin stands in loose connection with the crimping bar and moves the
crimping bar linearly. The rotational movement can also be
converted into the linear movement by means of a connecting rod.
Eccentric crimping presses work rapidly and are economic in
manufacture.
[0008] However, the fixed stroke preset by the eccentric pin is
disadvantageous in these crimping presses. For tools with different
stroke lengths, a mechanical action has to be undertaken at the
crimping press, in that the dead centers of the eccentric pin are
displaced or the shaft with the eccentric pin is exchanged. A
subsequent adjustment is necessary in each case.
SUMMARY OF THE INVENTION
[0009] Accordingly, it is an object of the present invention to
provide a crimping press, in which the tool stroke is settable, for
the production of crimp connections while avoiding the
disadvantages of the known equipment.
[0010] Pursuant to this object, and others which will become
apparent hereafter, one aspect of the present invention resides in
a method for controlling a crimping process for connecting a
contact with a conductor, which method comprises the steps of
driving a crimping tool of a crimping press from a start position
into a crimping position and subsequently into an end position, and
selecting the start and end positions of the crimping tool for
processing different contacts.
[0011] In another embodiment of the inventive method the crimping
tool is moved between the start position and the end position by a
rotational movement in which the start and end are at different
locations.
[0012] In still another embodiment of the inventive method the
crimping tool, in a succeeding crimping process, is moved in a
direction of rotation that is opposite to a direction of rotation
of a preceding crimping process.
[0013] In still a further embodiment of the inventive method the
respective position of the crimping tool is detected and used for
controlling the crimping. Furthermore, the method includes
selecting any single one of a crimping process for checking the
crimping connection, a crimping process with an intermediate stop
for positioning the conductor, and a crimping process with a
preselected stroke.
[0014] Another aspect of the invention resides in an apparatus for
producing a crimping connection, which apparatus includes a
motor-driven crimping tool and means for selectively controlling
position and movement of the crimping tool.
[0015] In another embodiment of the apparatus the crimping tool
includes a drive motor while the control means includes a computer
operatively connected to the drive motor so as to control the drive
motor according to selectable prescribing data and in dependence on
a respective position of the crimping tool.
[0016] In still another embodiment of the inventive apparatus the
control means includes a transmitter operatively arranged to detect
the respective position of the crimping tool. The control means can
further include an inverter operatively connected between the
computer and the drive motor so as to control the drive motor in
accordance with the specification data from the computer.
[0017] In yet a further embodiment of the crimping apparatus
pursuant to the invention, an operator terminal is provided which
is in operative communication with the control means. The operator
terminal includes a keyboard or keypad and a display for input and
visualization of user and system data. Furthermore, a rotary knob
is provided at the operator terminal for selecting the start and
end position of the crimping tool.
[0018] The advantages achieved by the invention are essentially to
be seen in that in the processing of different contacts no
re-equipping of the crimping press is necessary and that also small
contacts are able to be processed. It is further of advantage that
no sensors for monitoring the start position or intermediate
position of the tool with the dies are needed. With the crimping
press according to the invention the number of crimping processes
per unit time can be substantially increased without change in the
mechanical system. Moreover, the control of the crimping press
recognizes the exact tool position at any time, whereby a simple
evaluation of the crimping forces is made possible and other
machines participating in the crimping process can be
synchronized.
[0019] The various features of novelty which characterise the
invention are pointed out with particularity in the claims annexed
to and forming a part of the disclosure. For a better understanding
of the invention, its operating advantages, and specific objects
attained by its use, reference should be had to the drawing and
descriptive matter in which there are illustrated and described
preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] FIG. 1 shows a crimping press with a tool for production of
a crimp connection;
[0021] FIG. 2 shows the tool with crimping dies in the lower dead
center position;
[0022] FIG. 3 shows the tool with crimping dies in the upper dead
center position;
[0023] FIGS. 4, 5, 6 show the steps of a crimping process for
simultaneous production of an insulation crimp and a wire
crimp;
[0024] FIG. 7 shows details of a wire crimp;
[0025] FIG. 8 shows a rotation diagram of the crimping press with
constant rotation and maximum stroke for contacts with an open
crimp zone;
[0026] FIG. 9 shows a rotation diagram of the crimping press with
constant rotation, maximum stroke and intermediate position for
contact centering for contacts with a closed crimp zone;
[0027] FIG. 10 shows a rotation diagram of the crimping press with
alternating rotation and maximum stroke for contacts with an open
crimp zone;
[0028] FIG. 11 shows a rotation diagram of the crimping press with
alternating rotation and smaller stroke for contacts with an open
crimp zone;
[0029] FIG. 12 shows a rotation diagram of the crimping press with
alternating rotation, maximum stroke and intermediate position for
contact centering for contacts with a closed crimp zone;
[0030] FIG. 13 shows a rotation diagram of the crimping press with
alternating rotation, smaller stroke and intermediate position for
contact centering for contacts with a closed crimp zone;
[0031] FIG. 14 shows the construction, in terms of principle, for a
resolver for measuring angular positions;
[0032] FIG. 15 shows a resolver interface; and
[0033] FIG. 16 shows a schematic of a press control.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0034] A stand 1 without a right-hand side wall, is shown in FIGS.
1-16. A motor 2 and a transmission 3 are mounted at the stand 1.
Moreover, first guides 4, are provided at the stand 1 and a
crimping bar is guided in the first guides 4. A shaft 6 driven by
the transmission 3 has an eccentric pin 7 at one end, and a
resolver 37 for detection of the rotational angle is coupled to the
other end. The crimping bar 5 consists of a slide member 9 guided
in the first guides 4 and a tool holder 10 with a retaining fork
11. The slide member 9 stands in loose connection with the
eccentric pin 7, wherein the rotational movement of the eccentric
pin 7 is converted into a linear movement of the slide member 9.
The maximum stroke of the slide member 9 is determined by the upper
dead center and the lower dead center positions of the eccentric
pin 7. The tool holder 10 actuates a tool 12, which, together with
an anvil 13 belonging to the tool 12, produces the crimp
connection. The stroke can be precisely adjusted by means of an
adjusting screw 14. An operator terminal 15 is provided as an
interface between an operator and the crimping press. The operator
terminal 15 comprises a rotary knob 17 and a key pad 18 for the
input of operating data and commands into a control 16 and a
display 19 is provided for visualisation of data.
[0035] FIGS. 2 and 3 show details of the tool 12 for production of
a crimp connection. A die carrier 21 is guided in a tool housing 20
and comprises a carrier head 22, which stands in loose connection
with the retaining fork 11 of the tool holder 10. A first crimping
die 23 and a second crimping die 24, which together with the
correspondingly constructed anvil 13 produce the crimp connections,
are arranged at the die carrier 21. FIG. 2 shows the crimping dies
23, 24 in the lower dead center position of the eccentric pin 7, in
which the production of the crimp connection is concluded. FIG. 3
shows the crimping dies 23, 24 in the upper dead center position of
the eccentric pin 7. The die stroke is determined by the two dead
center positions.
[0036] FIGS. 4 to 6 show the crimping process, in which the end of
a conductor 25 is connected with a contact 26. An open crimp zone
27 of the contact 26 has a first double tongue 28 for the
insulation crimp and a second double tongue 29 for the wire crimp.
FIG. 4 shows the crimping dies 23, 24 in the upper dead center
position. The end of the conductor insulation lies in the first
double tongue 28 and the stripped conductor piece lies in the
second double tongue 29. As shown in FIG. 5, upon lowering of the
crimping dies 23, 24 the double tongues 28, 29 are pressed together
by means of wedge-shaped recesses 30 of the crimping dies 23, 24. A
dome-shaped upper end of the recess 30 gives the final form to the
double tongue 28 or 29 together with the conductor insulation or
the conductor wire. FIG. 6 shows the finished crimp connection with
an insulation crimp 33, in which the first double tongue 28 is
pressed around the conductor insulation 31, and with a wire crimp
34, in which the second double tongue 29 is pressed around the
conductor wire 32. FIG. 7 shows how in the wire crimp 34 the second
double tongues 29 are squashed together with the conductor wire 32,
which is constructed as a strand.
[0037] FIGS. 8 to 13 show the rotation diagram of the eccentric pin
7. The rotational movement of the eccentric pin 7 during the
straight crimping processes is illustrated by solid line. The
rotational movement of the eccentric pin 7 during the non-straight
crimping processes is illustrated by dashed line. FIGS. 8 and 9
show the prior art, in which the eccentric pin 7 rotates in the
same direction with maximum stroke in each crimping process. Start
and end position A, E, as well as intermediate position Z are
picked up by means sensors 35, usually proximity switches,
detecting the eccentric pin 7 and the crimping press is controlled
by the corresponding signals. Start and end position A, E as well
as intermediate position Z are preset by the geometric arrangement
of the sensors 35 and can be changed only by changing the sensor
arrangement.
[0038] The rotation diagrams of FIGS. 10 to 13 show the control of
the crimping press according to the invention. In, for example, the
straight crimping processes the eccentric pin 7 rotates in one
direction and in the non-straight crimping processes the eccentric
pin 7 rotates in an opposite direction. No sensors are provided for
detection of the start and end position A, E, or the intermediate
position Z and the crimping position C. The detection of every
position of the eccentric pin 7 is effected by means of the
resolver 37 driven by the shaft 6. The construction and mode of
function of the resolver 37 are more closely explained below in
connection with FIGS. 14 and 15. According to FIGS. 11 and 13 a
crimp connection can also be produced with a smaller stroke than
the maximum stroke. The control 16 recognizes at any time the
position of the eccentric pin 7 and can, by corresponding motor
commands, shorten the stroke and thus the crimping process by the
path denoted by 36. Start and end position A, E of the eccentric
pin 7 are no longer at the same place in a crimping process. No
mechanical action, for example an exchange of the shaft, is
necessary for changing the stroke length.
[0039] FIGS. 14 and 15 show the construction, in terms of
principle, and the mode of function of the resolver 37, which
delivers an absolute signal per revolution and is insensitive with
respect to vibrational loading and temperature. By virtue of this
mechanical construction its angle information is maintained even in
the case of loss of voltage. The resolver consists of a stator 38
and a rotor 39, which is driven by the shaft 6, and serves for the
measurement of angular positions. A first stator winding 40 and a
second stator winding 41 are arranged at the stator 38 and a rotor
winding 42 is arranged at the rotor 39. The rotor winding 42 is
excited by an alternating voltage U1 with constant amplitude and
frequency, for example 5000 Hz. The second stator winding 41 is
arranged displaced relative to the first stator winding 40 through
90 degrees. The voltage U1 respectively generates the two voltages
Usin and Ucos at the terminals of the stator windings 40, 41
through electromagnetic coupling. These two voltages have the same
frequency as U1. However, the amplitude is proportional to the sine
and cosine of the mechanical angle .theta.. The energizing of the
rotor winding 42 is effected by way of an oscillator 43. In the
case of a resolver with a pole pair, the amplitude of the two
voltages Usin and Ucos in each case runs through a sine oscillation
per mechanical revolution. A resolver interface 44 evaluates the
sine signal and the cosine signal of the resolver 37 with, for
example, a resolution of 0.35 degrees and converts the angle
.theta. into a digital value. The resolver interface 44 is
connected at the output to a bus system 45 of the control 16.
[0040] FIG. 16 shows details of the control 16 for the crimping
press. A converter 47 equipped at the output with a power line
filter 46 converts the power supply voltage into a direct voltage,
by which an inverter 48 is energized. Controlled semiconductor
switches Gu . . . Gz of the inverter 48 chop the direct voltage, in
a pulse-width modulation process, into three rectangular
alternating voltages, which generate sinusoidal currents of
variable frequency in the motor 2. The rotational movement is
transmitted by the motor 2 to the transmission 3 and then to the
shaft 6, at one end of which is arranged the eccentric pin 7 and at
the other end of which is arranged the resolver 37. The eccentric
pin 7 displaces the crimping bar 5 into a linear movement. A pulse
generator 49 reduces the pulse pattern which is necessary for the
drive control of the semiconductor switches Gu . . . Gz and which
is supplied to a drive stage 50, which is connected at the output
with the control lines of the semiconductor switches Gu . . . Gz. A
processor 51 controls all functions of the crimping press. The bus
system 45 is available for data exchange between the processor and
the peripheral blocks. A power supply 52 generates the auxiliary
voltages necessary for operation of the control 16. A
quartz-controlled pulse generator 53 generates the clock frequency
for the processor 51. A battery-supported read-write memory 54
serves as a working memory for the processor 51. The program for
control of the crimping press is filed in a read only memory 55.
Other machines participating in the crimping process, such as, for
example, a conductor feeder or a contact feeder, control devices,
safety circuits, etc., are designated by the reference symbol 56
and communicate with the control 16, for example for
synchronization, via the bus system 45. The operator terminal 15 is
connected with the processor 51 by means of a serial interface 57.
Menu-directed, user-specific data, such as password, language,
units, etc., and operation-specific data, such as acceleration,
deceleration, frequency of the motor and position point along the
stroke for synchronization of the peripheral machines and devices 6
participating in the crimping process, can be input at the operator
terminal 15. Moreover, system items of information,
service-relevant data, statistical evaluations, protocol data of
the communication, drive data, etc, can be accessed via operator
terminal 15. Modes of operation, such as calibration of the start
position of the crimping bar 5, set-up operation for prescription
of the stroke necessary for the respective tool, triggering of a
single crimping process for checking of the crimp connection,
crimping process with intermediate stop for positioning of the
contact and subsequent pressing of the contact, crimping process
with preselected stroke, etc., can also be prescribed in a
menu-directed manner via operator terminal 15 for the control 16,
whereby the crimping bar 5 and thus the tool 12 are positionable by
means of the rotary knob 17.
[0041] The principle of the selectable stroke can also be used at,
for example, crimping presses in which the linear movement of the
crimping tool is produced directly by means of linear drives. A
linear transmitter, which detects the tool position along the
stroke path, is used instead of the resolver.
[0042] The invention is not limited by the embodiments described
above which are presented as examples only but can be modified in
various ways within the scope of protection defined by the appended
patent claims.
* * * * *