U.S. patent number 3,837,460 [Application Number 05/330,318] was granted by the patent office on 1974-09-24 for high-speed driving device for printer or the like.
This patent grant is currently assigned to Kabushiki Kaisha Seikosha. Invention is credited to Yoshinori Chida, Naonobu Sawada.
United States Patent |
3,837,460 |
Chida , et al. |
September 24, 1974 |
HIGH-SPEED DRIVING DEVICE FOR PRINTER OR THE LIKE
Abstract
A high-speed driving device for use in a high-speed printer or
the like. The printer has actuatable printing elements each
actuated from a rest position to a printing position. The
high-speed driving device actuates each printing element with a
plurality of actuators each comprising an electromagnetic system
having a driving or operating electrical coil receptive of current
pulses for developing opposite polarities in its core in
conjunction with pole pieces forming a magnetic field for rocking
to an operative position and to an inoperative rest position the
core having a pole varied thereon and extending into a gap between
the pole pieces. The core is constructed with a multiplicity of
extensions or lever arms, one of which is normal to the core
portion within the coil and engages a corresponding actuatable
element to actuate it to its operative position when the core is
rocked. The core is restored to its rest position by application to
the operating coil of current of opposite polarity to the current
actuating it to its operative position. A spring restores each
actuatable printing element to its rest position in readiness for a
next printing step. Each core is rockably mounted in a carriage for
travel relative the actuation elements so that high-speed printing
can be carried out.
Inventors: |
Chida; Yoshinori (Matsudo,
JA), Sawada; Naonobu (Tokyo, JA) |
Assignee: |
Kabushiki Kaisha Seikosha
(Tokyo, JA)
|
Family
ID: |
11828371 |
Appl.
No.: |
05/330,318 |
Filed: |
February 7, 1973 |
Foreign Application Priority Data
|
|
|
|
|
Feb 8, 1972 [JA] |
|
|
47-13265 |
|
Current U.S.
Class: |
400/124.14;
101/93.05 |
Current CPC
Class: |
B41J
2/275 (20130101) |
Current International
Class: |
B41J
2/275 (20060101); B41J 2/27 (20060101); B41j
003/10 () |
Field of
Search: |
;197/1 ;101/93C |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Pulfrey; Robert E.
Assistant Examiner: Rader; R. T.
Attorney, Agent or Firm: Burns; Robert E. Lobato; Emmanuel
J. Adams; Bruce L.
Claims
What we claim and desire to secure by letters patent is:
1. A high-speed driving device for high-speed printers and the like
comprising, means forming a flux path having opposite polarity
poles and an air gap therebetween, a rockable lever rockably
mounted having a first lever arm made of magnetic material
extending into said air gap and a second lever arm at an angle
relative to the first lever arm and actuated thereby from a rest
position to an operative position for impacting an actuatable
element and restored to said rest position, means to actuate said
first lever arm thereby to actuate said second lever arm comprising
an operating coil stationary relative to said rockable lever for
varying said first lever arm fro one polarity to another to effect
attraction alternately by said poles of opposite polarity to rock
said rockable lever from a rest position to an operative position
and restore it to a rest position thereof, means rockably mounting
said rockable lever, means to apply current pulses serially to said
operating coil to effect said rocking, means to apply said current
pulses to said operating coil, an actuatable element disposed
freely movable independently of said second lever arm and normally
biased to a rest position in which said second lever arm impacts it
to actuate said actuatable element, and means biasing the
actuatable element to said rest position thereof.
2. A high-speed driving device for high-speed printers and the like
according to claim 1, in which first lever arm comprises a core in
said operating coil.
3. A high-speed driving device for high-speed printers and the like
according to claim 2, including a travelling carriage mounting said
lever and said coil for moving them selectively to a plurality of
discrete positions, and means to move the carriage.
4. A high-speed driving device for high-speed printers and the like
comprising, means defining a magnetic circuit having two poles of
opposite polarity and an air gap therebetween, a plurality of
actuators comprising rockable levers each having a first lever arm
made of magnetic material extending into said air gap, each
rockable lever having a second lever arm at an angle relative to
the first lever arm, means for said actuators to actuate said
rockable levers comprising operating coils corresponding in number
to the number of rockable levers and stationary relative to said
rockable levers, each operating coil having said first lever arm of
a corresponding rockable lever extending therethrough as a core,
means to apply series current pulses to the operating coils to vary
the magnetic polarity of the individual cores to different
polarities for repulsion and attraction by the two poles between
which each is disposed for actuation from a rest position to an
operative position and restoring thereof to said rest position,
means to apply said current pulses to said coils, whereby said
second lever arm is rocked from a rest position to an operative
position for impacting a member operable thereby, a plurality of
actuatable elements disposed freely movable independently of said
actuators, said actuatable elements corresponding in number to the
individual second lever arms of said rockable levers, means biasing
the actuatable elements individually to a respective rest position
at which said actuatable elements are impacted individually by a
corresponding second lever arm.
5. A high-speed driving device for high-speed printers and the like
according to claim 4, in which said means defining said flux path
comprises a pair of elongated pole pieces defining said air gap as
an elongated air gap, each of the first lever arms being disposed
sequentially in said air gap.
6. A high-speed driving device for high-speed printers and the like
according to claim 5, in which each of said rockable levers
comprises a third lever arm made of magnetic material extending
toward said pole pieces and having a polarity opposite to a pole
piece next to which it is adjacent thereby to magnify the impacting
of said second lever arm.
7. A high-speed printer comprising, a plurality of actuatable
printing devices freely movable independently and operable from a
rest position to an operative position for effecting printing, a
plurality of actuators for impacting the actuatable printing
devices individually for actuating them comprising, means defining
pole pieces defining an air gap between two poles of opposite
polarities, a plurality of rockable levers each having a lever arm
of magnetic material extending into said air gap and a second lever
arm at an angle relative to the first lever arm for impacting the
printing devices, a plurality of operating coils stationary
relative to the corresponding actuators and each having the first
arm of a corresponding lever arm extending therethrough as a core,
means for energizing the operating coils selectively for developing
different polarities in the individual cores thereby to rock the
rockable lever arms from a rest position to a position for
impacting the printing devices and to return them to said rest
position, and biasing means to restore the printing devices to a
corresponding rest position after impaction thereof for printing
and after the restoration of said rockable lever arms to said rest
position thereof.
8. A high-speed printer according to claim 7, in which said second
lever arm of each rockable lever is disposed vertically, a common
shaft rockably mounting said rockable levers, travelling means
mounting said rockable levers and said printing devices for travel
jointly along a given path.
9. A high-speed printer according to claim 8, including a platen
relative to which said travelling means travels.
10. A high-speed printer according to claim 7, in which said pole
pieces comprises two elongated pole pieces, and in which said air
gap is elongated.
Description
BACKGROUND OF THE INVENTION
The present invention relates to high-speed printers and more
particularly to a high-speed driving device for printers and the
like.
In known high-speed driving devices for actuating printing elements
in a high-speed printer, the driving device is provided with a
solenoid electromagnet that is energized for actuating the printing
elements of the printer. The use of the known type of solenoid
electromagnets presents a serious problem with respect to attaining
high-speed in these apparatus in that friction occurs between the
core and the yoke or mount for the core along the axial path of
travel of the core during its movement and actuation. Furthermore,
it is difficult to prevent mechanical oscillation because the core
is generally restored or returned by a return spring which
inherently introduces mechanical oscillations into the system.
Accordingly, the response of the core to applied electrical signals
applied to the operating coil is generally unsteady and the life of
the driving device is reduced by this type of solenoid
construction.
SUMMARY OF THE INVENTION
It is a principal object of the invention to provide a high-speed
electromagnetic driving device for use in a printer suitable for
high speed and stable operation.
Another object of the present invention is to provide a high-speed
driving device that eliminates the disadvantages of the known
high-speed printing driving devices.
A high-speed driving device according to the invention comprises a
plurality of actuators carried on a carriage for actuating
actuatable printing elements. Each actuator has an electromagnetic
structure having an electrical coil receptive of current pulses
from a control circuit for electromagnetically rocking a rockable
magnetic core in the coil to an operative position and back to its
rest position. Each core is provided with a multiplicity of arms,
one of which functions as the actuating portion of the core that
actuates the individual printing elements. A pair of plate pole
pieces provide a magnetic field that coacts with each coil and core
and for effecting its actuation.
BRIEF DESCRIPTION OF THE DRAWING
Other features and advantages of the high-speed driving device will
appear from the following description of an example of the
invention, the novel features pointed out in the appended claims
and attached drawings in which:
FIG. 1 is a plan view of a high-speed printer embodying the present
invention;
FIG. 2 is a section view taken along section line II--II in FIG.
1;
FIG. 3 is a circuit diagram of control circuitry for the high-speed
driving device and printer according to the invention; and
FIG. 4 is a fragmentary section view of a second embodiment of a
part of the high-speed driving device according to the
invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
According to the invention, a carriage 1 of a wire-drive type
printer is supported on a base 2 and is driven or moved in opposite
directions axially of the worm gear 3. The carriage carries a
plurality of actuators comprising a plurality of electromagnetic
systems. Each actuator has magnetic field-forming means which
comprise plate pole pieces 5, 5a and a permanent magnet 4. These
are common to each actuator. The pole pieces 5, 5a define an
elongated air gap between two spacers 6, 6a made of non-magnetic
material intermediate a north pole N and a south pole S of the pole
pieces, as illustrated.
A shaft 7 rockably mounts actuator elements or levers each
comprising two lever arms. A first lever arm 8 functions as a coil
core, and a second lever arm 9 normal thereto which functions to
carrying out the actuating function later described. Each actuator
has a bobbin 10 supported in a support 11 and a coil 12 wound on
the bobbin for actuating rockably the rockable core 8 as later
described. Each core 8 is provided with an end portion at a free
end thereof which forms a pole, for example a pole N, and is free
to be rocked from a rest position shown to rock the actuating or
second lever arm 9 to an actuating position to be described. The
core 8 has clearance within the bobbin to carry out this rocking
movement.
The spacers 6, 6a are made of non-magnetic material and prevent the
individual cores from banging up against the pole pieces 5, 5a
which would result in decreasing the high-speed response of the
apparatus. Those skilled in the art will recognize that instead of
the spacers, appropriate stops may be provided to limit the
movement of the cores to maintain the mode of operation
desired.
In a printing press of the present type, five electromagnetic
assemblies or structures as illustrated on the lefthand side
position of the apparatus in FIG. 2, are provided on the left side
and four on the right side disposed for actuating of the printing
elements as the carriage travels axially of the worm gear 3 for
carrying out printing operations as hereinafter described. The
apparatus thus has two sets of elongated pole pieces, as shown in
FIG. 2, and nine coils 12 and corresponding coil cores 8. The
placing of the coils and cores on opposite sides of the axis of the
support shaft 7 permits construction of a more compact
carriage.
The upper end portions of each driving lever or arm 9 protrudes
upwardly from the casing above the carriage through a longitudinal
slot, as shown in FIG. 1, and will actuate a series of wires 16
connected to individual pins 17. The pins 17 are supported by
pin-supporting plates 18, 19 and are biased toward the right into
engagement with individual driving lever arms 9 by biasing or
restoration springs 20. The actuation wires 16 are slidably
supported by arcuate wire plates 21, 22 and extend through a wire
guide block 23. The distal end of the individual wires is disposed
adjacent a printing platen 14. The wires are used for executing
printing of dots on a paper 24 in conjunction with a printing or
inking ribbon 25 interposed between the platen 14 and the
individual wires 16. In the present invention, nine wires are
provided and their distal ends or tips are arranged vertically in a
row facing the platen 14. Of course, other types of printing
elements may be provided other than wire to be actuated by the
actuators of the high-speed driving devices as will be seen.
In order to drive the actuator's driving lever arms 9, current
pulses flowing in opposite directions are applied to the individual
coils 12 for magnetizing the individual cores 8 in opposite
polarities. When current is applied to form a north pole N, as
illustrated in FIG. 2, the core will be attracted downwardly by the
pole of the pole piece of opposite polarity and simultaneously
repelled by the upper pole piece pole N, so that the driving lever
9 engages a corresponding pin 17 and drives it toward the left.
When a current of opposite polarity flows through the operating
coil 12 the core is magnetized so that a pole of opposite polarity
is formed thereon and the core will be restored to its rest
position at a high speed mode of operation. Thus when the
individual cores are actuated to their operative position and drive
the corresonding actuator lever arm to its driving position, the
individual wires will carry out a printing operation and subsequent
to the printing the energizing of the individual coils in an
opposite polarity will restore the cores to their rest
position.
The control of the individual cores is carried out by a
corresponding control driving circuit, of the type illustrated in
FIG. 3, for controlling the application of current pulses to the
individual coils controlling the corresponding cores. The circuit
for controlling one of the cores is illustrated and the control
circuits for the other cores may be constructed accordingly.
The individual control or driving circuits each comprise a
symmetrical circuit configuration in which inputs for controlling
the desired core are applied to its corresponding control circuit
across input terminals 26, 27, one of which is grounded and the
other in series with a resistance R.sub.1 connected to the base of
a transistor Tr.sub.1 connected through its emitter to a second
transistor Tr.sub.2 as illustrated. The second transistor has its
base grounded and its collector is connected to a junction to which
a resistor R.sub.2 is connected which is connected to a power
source E. A third transistor Tr.sub.3 has its emitter connected to
the power source E, its base connected to a resistor R.sub.3 in
series with a diode D.sub.1 and both are connected to the collector
of the second transistor. A diode D.sub.3 is connected to collector
of the third transistor and the power source. A symmetrical
configuration is provided as illustrated.
In a subcircuit having a symmetrical configuration with that
described has second input terminals 29, 30. One terminal is in
series with a base resistor R.sub.6 connected to the base of a
first transistor Tr.sub.6 is connected to a second transistor
Tr.sub.5 having its collector connected to a junction to which a
resistor R.sub.5, a diode D.sub.2 and base resistor R.sub.4,
connected to the base of a third transistor Tr.sub.4, are
connected. A diode D.sub.4 is connected similarly to the diode
D.sub.3 in the subcircuit first described. A load L corresponding
to one of the operating coils is connected to both symmetrical
circuits.
When a positive current pulse P.sub.1 is applied between the input
terminals 26, 27, the first transistor Tr.sub.1 is rendered
conductive and electric current flow from a power source connected
at the terminal E through the emitter-base connection of the third
transistor Tr.sub.3 and its base resistor R.sub.3 and the series
diode D.sub.1 and connector-emitter of the second transistor
Tr.sub.2. Therefore, the third transistor Tr.sub.3 is rendered
conductive and electric current flows in the load L, corresponding
to the coils 12, in the direction of the arrow 28.
When a positive pulse P.sub.2 is applied between the second set of
input terminals 29, 30, the transistor Tr.sub.5 is rendered
conductive and electric current flows in the direction shown by an
arrow 31. In this manner, electric current flows alternately in
opposite directions in the load L by virtue of two series pulses
applied alternately to the two sets of input terminals. When the
second pulse is applied, the core 8 is returned to its rest
position as before described.
A second embodiment of a high-speed electromagnetic driving device
according to the invention is illustrated fragmentarily in FIG. 4.
In this embodiment, a permanent magnet 32 is mounted between
elongated plate pole pieces 33, 33a similarly to the
first-described embodiment. A pivot shaft 34 is mounted centrally
of a carriage assembly designated generally as 35. A plurality of
cores in actuators, such as a core 36, made of magnetic material
and each having a related driving lever arm 37 upstanding thereto
are rockably supported as before described. A supplementary lever
arm 38 is provided on each actuator and is made of the same
material as the core lever arm 36 and functions to form a closed
magnetic path in conjunction with the pole pieces 33, 33a to
minimize the magnetic resistance or reluctance. The free end
portion of each supplementary lever arm has a pole thereon of
opposite polarity than that of the pole piece to which it is
adjacent. A bobbin 39 supports a coil 40 for each actuator
similarly to the embodiment described before. In this construction,
the core 36 and the supplementary lever arm 38 are attracted to the
magnetic field-forming pole pieces 33, 33a so that the driving
power of the driving lever 37 is increased when pulses are applied
to the operating coil 40 in the manner heretofore described and the
individual cores are restored as before described. While the
high-speed driving device has been described as applicable to
high-speed printers, those skilled in the art will readily
understand the device is applicable to punching apparatus and the
like.
* * * * *