U.S. patent application number 16/762189 was filed with the patent office on 2020-11-19 for method and device for the needle-free injecting of fluid into a substrate, and fluid container for use in the method and the device.
The applicant listed for this patent is CC - PHARMA GMBH. Invention is credited to Fritz SCHMITT.
Application Number | 20200360611 16/762189 |
Document ID | / |
Family ID | 1000005003120 |
Filed Date | 2020-11-19 |
United States Patent
Application |
20200360611 |
Kind Code |
A1 |
SCHMITT; Fritz |
November 19, 2020 |
METHOD AND DEVICE FOR THE NEEDLE-FREE INJECTING OF FLUID INTO A
SUBSTRATE, AND FLUID CONTAINER FOR USE IN THE METHOD AND THE
DEVICE
Abstract
The invention proposes a method and a device for needleless
injection of liquid into a substrate, in particular of a liquid
pharmaceutical or cosmetic preparation into a biological tissue,
making it possible in a particularly advantageous manner to
reliably inject a liquid completely into the substrate without a
needle. In accordance with the invention, this is achieved by a
sequential injection, wherein a first partial quantity of the
liquid first exits from an outlet nozzle at a very high outlet
velocity as a fine liquid jet under high pressure generated in the
liquid by means of a impulse shock and enters the substrate and
creates an injection channel in the substrate, into which a second
partial quantity of the liquid is then introduced at lower pressure
and lower velocity. Preferably, the ejected liquid jet is set in
rotation around its jet axis before it impinges on the substrate,
so that the jet receives a helical movement and thus practically
drills into the substrate without splashing away laterally.
Inventors: |
SCHMITT; Fritz; (Rosport,
LU) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
CC - PHARMA GMBH |
Densborn |
|
DE |
|
|
Family ID: |
1000005003120 |
Appl. No.: |
16/762189 |
Filed: |
November 9, 2018 |
PCT Filed: |
November 9, 2018 |
PCT NO: |
PCT/IB2018/058812 |
371 Date: |
May 7, 2020 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61M 2205/8287 20130101;
A61M 2250/00 20130101; A61M 5/31583 20130101; A61M 2005/31588
20130101; A61M 5/3007 20130101; A61M 2205/8206 20130101 |
International
Class: |
A61M 5/30 20060101
A61M005/30; A61M 5/315 20060101 A61M005/315 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 10, 2017 |
DE |
10 2017 126 493.0 |
Claims
1.-6. (canceled)
7. An injection device for the needleless injection of a liquid
into a substrate, particularly for injection of liquid
pharmaceutical or cosmetic product into a biological tissue,
comprising a housing, a liquid supply accommodated or arrangeable
in the housing, an outlet nozzle and an ejector device for ejecting
liquid from the liquid supply through the outlet nozzle, wherein
the ejector device has means for generating an impulse shock acting
at least on a first quantity of liquid in the liquid supply.
8. The device according to claim 7, wherein the means of the
ejector device for generating the impulse shock comprise an ejector
plunger acceleratable to an impulse velocity, with whose mass
accelerated to the impulse velocity the first quantity of liquid
can be acted on.
9. The device according to claim 7, wherein the liquid supply is
actable on by means of an ejector piston actuatable by the ejector
device, which ejector piston in turn is actable on or formed by the
ejector plunger.
10. The device according to claim 7, wherein the ejector device has
an electromagnetic drive for the ejector plunger.
11. The device according to claim 7, wherein the ejector device has
an acceleration section for the ejector plunger.
12. The device according to claim 10, wherein the electromagnetic
drive is arranged at a rear end of the housing spaced from the
outlet nozzle or approximately in the middle of the housing,
wherein the acceleration section extends between the outlet nozzle
and the rear end of the housing.
13. The device according to claim 10, wherein the electromagnetic
drive has a magnetic coil formed on the ejector plunger itself as
well as an iron cylinder and/or a stator coil surrounding the
ejector plunger
14. The device according to claim 10, wherein the ejector plunger
is provided with an electric power storage device to supply the
electromagnetic drive with electric power.
15. The device according to claim 7, wherein the acceleration
section in the area in front of and behind the ejector plunger is
connected to pressure compensation openings.
16. The device according to claim 15, wherein the pressure
compensation openings are connected to each other via an overflow
line.
17. The device according to claim 7, wherein the ejector device
comprises means for generating an increase in pressure in the
liquid supply immediately following the exerted impulse shock.
18. The device according to claim 17, wherein means for generating
a pressure increase are substantially formed by the ejector plunger
which, after exerting the impulse shock, acts on the liquid supply
by means of a force-exerting drive.
19. The device according to claim 18, wherein the force-exerting
drive is the electromagnetic drive.
20. The device according to claim 7, wherein the liquid supply is
accommodated in a liquid container which can be arranged
replaceably in the housing.
21. The device according to claim 20, wherein the outlet nozzle is
arranged on the liquid container.
22. The device according to claim 8, wherein the outlet nozzle
comprises means for setting the liquid jet at least in its outer
area in rotation before its impingement on the substrate.
23. The device according to claim 7, wherein the outlet nozzle has
a nozzle outlet running substantially coaxial to the housing axis
of the housing.
24. The device according to claim 7, wherein the outlet nozzle has
a nozzle outlet running substantially in a plane normal to the
housing axis of the housing.
25. The device according to claim 7, wherein the outlet nozzle
and/or the front end of the housing is/are provided with a depth
indicator or a depth stop.
26. The device according to claim 7, wherein the liquid container
with the liquid contained therein together with the ejector plunger
is movably accommodated or accommodatable in the housing or an
acceleration section provided in the housing, respectively, and
that the housing has at its front outlet end a stop for the liquid
container.
27.-28. (canceled)
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a 371 U.S. National Phase of
International Application No. PCT/IB2018/058812, filed on Nov. 9,
2018, which claims the benefit of German Patent Application No. 10
2017 126 493.0, filed on Nov. 10, 2017. The entire disclosures of
the above applications are incorporated herein by reference.
BACKGROUND
[0002] This section provides background information related to the
present disclosure which is not necessarily prior art.
Technical Field
[0003] The invention relates to a method for needleless injection
of liquid into a substrate, in particular a liquid pharmaceutical
or cosmetic product into a biological tissue. The invention further
relates to an injection device for needleless injection of liquid
into a substrate, in particular of a liquid pharmaceutical or
cosmetic product into a biological tissue, comprising a liquid
supply, an outlet nozzle and an ejector device ejecting liquid in
the form of a liquid jet from the supply through the outlet nozzle.
Finally, the invention also relates to a liquid container for use
in carrying out the method according to the invention and/or in the
device according to the invention.
Discussion
[0004] To inject a liquid into a substrate, for example a liquid
pharmaceutical or cosmetic product into or under the skin of a
human or other living being, the liquid is usually injected through
an injection needle into the substrate, i.e. the human or animal
tissue. For this, the injection needle must first penetrate into
the substrate. As a result of the incision made by a cutting edge
at the needle tip, injuries occur which, although they usually heal
quickly in living tissue, regularly result in scar formation.
Furthermore, injections with injection needles always carry the
risk of infection.
[0005] There have therefore been various experiments in the past
with hypodermic jet injection devices for needleless injection to
bring a small amount of liquid, such as a vaccine or other drug, an
anesthetic or the like, directly through the skin surface into the
tissue while forgoing the use of an injection needle that can
penetrate into the substrate. Basically, the idea behind these
efforts was to penetrate the patient's skin solely by the pressure
of the liquid and to bring the injection medium to a desired depth.
However, the devices developed for this purpose were not able to
fulfill the expectations placed on them.
[0006] The injection devices proposed in the past for needleless
injection of liquids such as drugs have an energy storage such as a
spring mechanism, a pressure reservoir and/or a detonator which,
when triggered, causes a pressure increase in a liquid supply
contained in the device in order to eject liquid from the supply
through an outlet nozzle. The nozzle cross-section is as small as
possible and the pressure acting on the liquid supply is as high as
possible in order to produce a liquid jet with a small
cross-section and high jet velocity.
[0007] From US 2002/0143323 A1 an endoscopic device for
gastrointestinal epithelial removal is known, in which a probe is
supplied with a liquid. The liquid is supplied to the probe from a
supply container which can be acted on by a pressurized gas from a
gas bottle. US 2006/0149193 A1 discloses a device with a probe and
a liquid applicator, which has a liquid outlet for needleless
injection of a liquid into a biological tissue and a liquid conduit
leading to the liquid outlet. An associated liquid delivery device
has a drive device and is connectable to a pressure storage
pressure container as energy storage. The liquid delivery device
includes an expansion chamber which has a movable wall surface
which encloses the liquid to be injected and which can be acted
upon by a pressurized liquid.
[0008] Furthermore, devices are known which are used for needleless
injection of a liquid under the mucosa. For example, US
2009/0157114 A1 discloses an endoscope with a probe for needleless
injection under the mucosa. For this purpose, the probe emits a jet
of a sodium chloride solution, which penetrates the tissue due to
its small cross-section and concurrently high velocity. A pump unit
or, optionally, a force-enhancing lever is provided to convey the
sodium chloride solution and generate the respective pressure.
[0009] The known devices have so far proved to be little
successful, because the liquid jet produced by them breaks up
immediately after exiting the outlet nozzle and concurrently
reduces its velocity. When it impinges on the substrate, it then
tends to "mushroom", i.e. splash apart, so that at least some of
the liquid directed at the substrate surface does not penetrate the
substrate, but is drained off sideways from the point of impact. As
a result, it is unclear whether and how much liquid was actually
injected into the substrate. With the known devices it is in
particular not possible to bring liquid to a desired depth in the
substrate and to create a liquid depot with a certain amount of
liquid at this depth.
SUMMARY
[0010] This section provides a general summary of the disclosure,
and is not a comprehensive disclosure of its full scope or all of
its features.
[0011] The aspect of the invention is therefore to provide a method
and a device of the aforementioned type, which enables a reliable
injection of liquid into a substrate without the use of an
injection needle (cannula) pierced into the substrate.
[0012] This aspect is achieved with the method according to the
invention in that a pre-jet is generated by means of a first
partial quantity of liquid exiting the outlet nozzle at high
velocity, which pre-jet forms an injection channel in the
substrate, and that subsequently at least a second partial quantity
of liquid is passed into the substrate through the injection
channel generated by the pre-jet. The device according to the
invention is characterized in that the ejector device has means for
generating an impulse shock acting at least on a first quantity of
liquid in the liquid supply.
[0013] With the method and device according to the invention, a
first partial quantity of liquid is first ejected from the outlet
nozzle at very high velocity as a fine liquid jet with a small
cross-section. For this purpose, it is possible that at least in
the first partial quantity of liquid, an impulse shock (pressure
shock) is generated which causes this first partial quantity to
exit the device as a pre-jet at very high velocity as a result of
the liquid pressure suddenly rising to a very high value and to
impinge on the substrate and, with suitable selection of an
ejection nozzle provided on the device, to penetrate into the
substrate to a desired depth without significant resistance due to
the then very small jet diameter. It is also possible to provide
the high energy for the generation of the fine liquid jet with a
high outlet velocity from the outlet nozzle in that the liquid in
the injection device is first accelerated to an initial velocity
with a liquid container containing it and then, at the end of the
acceleration section, while the liquid container is decelerated at
a stop, the liquid at least partly continues its movement through
the outlet nozzle. In this advantageous procedure, a dynamic
pressure component is applied to the liquid by the acceleration in
the injection device, and the static pressure increase (impulse
shock) in the liquid is correspondingly smaller when the liquid
container is decelerated again after the acceleration and the
liquid is pushed out of the container through the outlet
nozzle.
[0014] The penetration depth of the liquid jet leaving the outlet
nozzle into the tissue depends--besides its jet diameter--on the
initial velocity of the liquid (dynamic pressure component) to
which it is accelerated in the device and the strength of the
impulse (static pressure component) exerted on the liquid, in
particular the first partial quantity. Preferably, the liquid or
the first partial quantity in the device, respectively, is
initially contained in an accommodation space for the liquid supply
and is in any case limited at an area by a shock inducer element
for inducing the impulse shock. The shock inducer element, which
can generally be any kind of means or design of the liquid supply
or its accommodation space, respectively, which allows a pressure
shock (impulse shock) to be introduced into the liquid contained in
the accommodation space, can be acted upon by an actuating means of
the ejector device, in particular an ejector plunger, which is
provided for this purpose and which is accelerated to high speed
after the device is triggered. When the actuating means hits the
shock element of the liquid container/accommodation space, or in
the embodiment, in which it is accelerated together with the liquid
contained therein and the ejector plunger jointly to a velocity,
when the liquid container hits the stop provided for this purpose
in the housing, respectively, the shock impulse inherent in the
actuating means due to its mass and its high velocity is
transferred to the liquid contained in the accommodating space and
causes a sudden, very large increase of pressure (pressure shock)
in the liquid, which results in a first partial quantity of the
liquid contained in the supply being ejected at a correspondingly
high pressure. When ejection is made through a nozzle with a small
cross section, this leads to a very high exit velocity of the
liquid jet of the ejected first partial quantity at the nozzle
outlet, where ambient pressure is then imposed on the liquid. The
first partial quantity ejected as a result of the pressure shock
thus exits the outlet nozzle at a very high speed, corresponding to
the very high pressure briefly generated in the liquid, as a liquid
jet--in a preferred embodiment as a liquid jet rotating around its
jet axis--and penetrates the substrate without any further
significant resistance. In the substrate, the liquid jet creates an
injection channel which is open at the substrate surface and
extends to an injection depth. This reached depth depends
essentially on the jet velocity at which the first subset impinges
on the substrate surface as well as on the jet thickness, which
essentially results from the cross-section of the outlet nozzle
through which the liquid exits the device. The velocity of the jet,
in turn, is a function (among others) of the pressure that is
actually achieved in the liquid only for a very short time as a
result of the impulse shock. By varying the velocity of the
actuating means (ejector plunger) and thus the amount of the
impulse given to it, the injection or penetration depth into the
substrate can be adjusted. Surprisingly, it has been found that
also a second partial quantity of liquid, which is subsequently
ejected from the nozzle of the device, penetrates without any
problems into the injection channel into the substrate previously
created by means of the first partial quantity, even if it is
ejected through the outlet nozzle at a significantly lower pressure
and accordingly impinges on the substrate at low velocity. This
second partial quantity then enters without further resistance at
the substrate surface into the previously created injection channel
open at the substrate surface, up to the end of the channel, i.e.
up to the penetration depth where the liquid is then distributed
essentially evenly around the channel. A second partial quantity of
the liquid can thus be injected to the desired depth in the manner
of a liquid depot.
[0015] For carrying out such a two- or multi-stage injection, an
ejector device with electromagnetic drive for the ejector plunger
has proved particularly suitable. The ejector plunger is first
accelerated by the electromagnetic drive in an acceleration section
in front of the liquid container (or together with it) to the
desired high plunger velocity and then in a very short time
interval, optionally abruptly, decelerated (optionally together
with the liquid container) to generate the impulse shock in the
liquid, whereupon the pressure in the liquid suddenly rises to a
very high value as described and the first partial quantity of
liquid is ejected from the container and leaves the outlet nozzle
at a very high velocity, preferably under rotation, i.e. a helical
movement. For injecting a second (and possible further) partial
quantity into the injection channel thus created by means of the
first partial quantity, the ejector plunger is inserted by means of
the electromagnetic drive in the manner of a syringe plunger of an
injection syringe with an ejection force at the shock inducer
element into the volume of the liquid accommodated in the liquid
supply and thereby expels the liquid through the outlet nozzle,
from where it enters the injection channel previously shot into the
substrate by the first partial quantity. The liquid supply can
therefore preferably be acted upon by means of an ejector piston
which can be actuated by the ejection device, which ejector piston
in turn can be acted upon by the ejector plunger or is formed by
it.
[0016] The electromagnetic drive may be located at a rear end of
the housing spaced from the outlet nozzle or a stop for the liquid
supply or ejector plunger, respectively, or approximately in the
middle of the housing, wherein the acceleration section extends
between the outlet nozzle or stop, respectively, and the rear end
of the housing.
[0017] The arrangement may be such that the electromagnetic drive
has a magnetic coil formed on the ejector plunger itself as well as
an iron cylinder and/or a stator coil surrounding the ejector
plunger. The ejector plunger may be provided with an electric power
storage device to supply the electromagnetic drive with electric
power. Of course, it is also possible to provide an external
electric power supply to supply the device with energy.
[0018] When the acceleration section in the area in front of and/or
behind the ejector plunger is connected to pressure compensation
openings, an influence of air compression or a resulting negative
pressure, respectively, in the acceleration section on the movement
of the ejector plunger is largely prevented. It is possible that
the pressure compensation openings are connected to each other via
an overflow line so that the air on the path in front of the
ejector plunger can flow through the overflow line behind the
plunger and thus ensure particularly reliable, rapid pressure
compensation.
[0019] As already mentioned, in an advantageous embodiment of the
invention, the ejector device comprises means for generating an
increase in pressure in the liquid supply immediately following the
exerted impulse shock, which means are expediently formed
substantially by the ejector plunger which, after exerting the
impulse shock, acts on the liquid supply by means of a
force-exerting drive. The force-exerting drive is preferably the
electromagnetic drive. When the liquid supply is accommodated in a
liquid container which can be arranged replaceably in the housing,
the outlet nozzle can be arranged on the liquid container, thus
ensuring in any case that the most suitable outlet nozzle is used
for a specific liquid to be injected.
[0020] Surprisingly, it has been found that a widening, i.e. an
increase in cross-section, of the liquid jet on its way from the
injection device to the substrate surface and the mushrooming
repeatedly observed with the known devices when impinging on the
substrate is very reliably avoided if the liquid jet rotates around
its own axis (jet axis) when impinging on the substrate with
preferably high jet velocity and small jet cross-section. It is
assumed that centripetal forces acting as a result of the rotation
hold the liquid particles (molecules) together, not only on the
path of the liquid jet from the outlet nozzle to the substrate
surface, but also when penetrating the substrate. In fact it seems
that, at least if the outlet nozzle is suitably designed, the
rotation of the jet after its exit from the outlet nozzle even
leads to a reduction of the cross-section and thus to an increase
in the velocity of the liquid jet, so that the liquid jet can
impinge on the substrate even at a higher velocity than it has when
exiting an outlet nozzle. Experiments have shown that the liquid
jet reliably penetrates biological tissue such as the skin of a
human or animal when injecting, even if the outlet nozzle of the
device according to the invention is positioned at a distance from
the tissue surface, i.e. the liquid jet has to bridge the distance
between the nozzle and the tissue surface as a "free jet", without
an increase in the distance having a negative effect on the
injection quality. The rotation, which is imposed on the jet before
it impinges on the substrate, is superimposed on the translatory
movement of the liquid in its jet direction to form a helical
movement, with which, according to the observations made, the jet
practically "drills" or "screws" itself into the substrate with
very low resistance at the surface of the substrate, forming an
inlet channel corresponding to the jet cross-section, wherein in
fact practically none of the liquid impinging on the substrate is
lost, i.e. does not penetrate into the substrate. Preferably, at
least the first partial quantity of liquid is set in rotation about
its jet axis before and during its passage through the outlet
nozzle of the device according to the invention.
[0021] In an advantageous embodiment of the invention, the rotation
of the liquid jet can be caused by means of at least one orifice
plate or nozzle with at least one screw-shaped or helical fluid
channel. Accordingly, the injection device according to the
invention can preferably comprise at least one approximately
screw-shaped or helical fluid channel at the outlet nozzle as a
means of setting the liquid jet in rotation. With the aid of the at
least one screw-shaped or helical fluid channel, the desired
rotational movement is firstly applied at least to the first
partial flow formed by the first quantity of the liquid flowing
through the outlet nozzle at least at the outer circumference of
the liquid jet, i.e. in the boundary region to the surrounding air,
wherein this rotational or screw movement is transmitted into the
interior of the liquid jet. It is also possible for the rotation of
the liquid jet to be caused by means of a rotating orifice plate or
nozzle, for which purpose the means provided by the device
preferably comprise at least one rotationally drivable part of the
outlet nozzle. A combination of the two rotation-generating
measures is also conceivable. It is also possible, in case of a
joint acceleration of the ejector plunger and the liquid supply
containing the liquid, to simultaneously set these two components
of the device, which are moved longitudinally along the
acceleration section, in rotation about their longitudinal axis, so
that the liquid contained in the supply is already
swirling/rotating when the liquid supply hits the stop and
maintains this angular momentum (swirling) when ejected through the
outlet nozzle.
[0022] The injection device according to the invention may
preferably be configured in such a way that the liquid supply, the
outlet nozzle and the ejector device are arranged/arrangeable in a
common housing. In this way, the device can be designed in a
particularly compact way, for example the device is easily operable
with only one hand as an injection device for injecting cosmetic or
pharmaceutical liquids into or under the skin of a human or
animal.
[0023] In an advantageous embodiment of the injection device, the
at least one screw-shaped or helical fluid channel can be arranged
at a nozzle wall limiting a passage in the outlet nozzle. For the
injection device, the arrangement may be such that the outlet
nozzle has at least one converging section whose cross-section
decreases in the flow direction of the ejected liquid, so that the
liquid is accelerated on its path through the converging section of
the outlet nozzle. In this case it has been found to be
advantageous when the at least one fluid channel extends over at
least a partial length of the converging section.
[0024] The outlet nozzle can also have at least one section of
constant cross-section, wherein the at least one fluid channel then
preferably (also) extends at least over a partial length of the
section of constant cross-section.
[0025] A particularly effective measure for imposing the desired
rotational or screwing movement on the liquid flowing through the
outlet nozzle consists in several fluid channels arranged
essentially rotationally symmetrically to the axis of the liquid
jet in the outlet nozzle. The plurality of fluid channels provides
a comparatively large, screw-shaped or helical contact or
interaction surface between the nozzle passage and the liquid
flowing through it, whereby a strong swirl or a comparatively fast
rotation of the liquid at the nozzle outlet can be achieved already
for a short axial extension of the nozzle (nozzle length). The
fluid channels can be arranged adjacent to each other on the
passage wall which limits the passage of the outlet nozzle.
[0026] Another particularly advantageous embodiment is that the at
least one fluid channel extends through the outlet nozzle in the
form of a helical pipe from the inlet side to the outlet side of
the outlet nozzle. In this embodiment, the rotational component of
movement, which the liquid jet has after its passage through the
outlet nozzle, is caused by the helical shape of the pipe through
which at least a partial flow of liquid flows and is set in
rotation about the axis of its streamline inside the pipe due to
the different radii on the inside and outside of the pipe helix.
When the pipe additionally has a helical radius decreasing from the
inlet side to the outlet side, this leads in an extraordinarily
advantageous way to a cyclone effect, namely to an increase in the
flow velocity of the (rotating) liquid jet when it exits from the
outlet nozzle formed in this way. A nozzle configured in this way
can therefore be called a cyclone nozzle. The described effect can
be further enhanced by providing two or more helical pipes, each
offset at an angle to each other in the manner of a double helix or
multiple helix. The effect of such a "cyclone nozzle" can also be
achieved with one or more helical fluid channels arranged on the
passage wall of a nozzle with a narrowing, in particular conical
nozzle passage and on the wall of the latter.
[0027] An equally expedient embodiment is when the outlet nozzle
has a central, preferably straight passage for a partial flow of
the liquid and when the at least one fluid channel helically
coaxially surrounds the central passage. A (second) partial flow
then flows through the fluid channel particularly helically
surrounding the central passage and in doing so is imposed with a
helical movement as described above before it combines with the
(first) partial flow after leaving the nozzle and transfers its
rotational or helical movement into the latter so that the entire
liquid flow consisting of both partial flows rotates about its jet
axis in an advantageous manner according to the invention, while it
impinges from the nozzle on the substrate and practically screws or
drills itself into the latter.
[0028] As already indicated, the outlet nozzle can be rotatably
mounted and can be set in rotation by means of a drive. In this
case it preferably has at least one, in particular preferably
several fluid channel(s) arranged eccentrically to the axis of the
fluid jet ejected from the outlet nozzle. The rotational movement
of the outlet nozzle or of the fluid channel(s) arranged therein,
respectively, about the axis of the liquid jet transfers its
rotational movement to the latter, so that the liquid jet has the
rotational movement according to the invention about its jet axis
when it exits the nozzle.
[0029] An embodiment which is particularly expedient from the point
of view of manufacturing results when the outlet nozzle has a
plurality of orifice plates arranged one behind the other in the
flow direction of the liquid in form of an orifice plate stack,
each of which has a slot opening extending over a part of the plate
diameter, the slot openings of orifice plates succeeding one
another in the orifice plate stack being arranged offset to one
another by an angular amount in the circumferential direction. The
orifice plates stacked one above the other with the slot openings
arranged therein and aligned offset by an angular amount then form
a central passage running essentially straight in the axial
direction of the nozzle as well as two helically staircase-like
stepped fluid channels arranged in the manner of a double helix
along the forming wall of the central passage. The arrangement is
preferably such that the amount of the offset in the
circumferential direction at the radially outer ends of the slot
openings is smaller than the width of the slot openings, so that
the helical (staircase)-shaped effect of the fluid channels
helically surrounding the central passage is ensured up to their
radially outermost edge regions.
[0030] It is particularly advantageous for the use of the injection
device as a cosmetic and/or pharmaceutical device, when the liquid
supply is formed by a liquid container, which can preferably be
replaceably arranged in the housing. When the liquid is contained
in a liquid container, for example in the form of a cartridge or an
ampoule, which is replaceably accommodated in the housing, not only
different liquids can be injected with one and the same device with
the least possible effort, for example liquid pharmaceutical
products of different types, as may be required for a series of
vaccinations, by simply subsequently inserting containers with
different liquids into the device one after the other. The
arrangement also has the advantage that the device can be cleaned
and/or sterilized particularly easily and thoroughly without the
liquid supply contained in it, which is particularly important for
its use in pharmaceutical areas, but also in the (commercial)
cosmetic sector.
[0031] It has proven to be very advantageous when the outlet nozzle
is arranged on the liquid container. This arrangement allows the
type and shape of the nozzle, in particular the passage for the
liquid provided therein, to be adapted in the best way possible to
the specific liquid contained in the liquid container and to be
injected. For example, when processing liquids of comparatively
high viscosity, such as hyaluronic acid products used in cosmetic
applications, e.g. for wrinkle injection or lip modelling, and in
medicine for injection into joints damaged by arthrosis, it may be
necessary to provide a nozzle with a larger passage cross-section
than for injecting simple physiological saline solution. The
arrangement of the outlet nozzle directly on the liquid container
then ensures that the appropriate outlet nozzle for the respective
liquid absorbed in the container is used in any case. For reasons
of hygiene in particular, it is preferred that the liquid
containers used in the injection device according to the invention,
especially those with outlet nozzles arranged thereon, are
disposable containers which are disposed of after a single use,
i.e. are not refilled.
[0032] The outlet nozzle can have a nozzle outlet running
essentially coaxial to the housing axis of the housing. The liquid
then exits in a direction coaxial with the housing axis of the
housing and thus generally perpendicular to the surface of the
substrate, because the housing is generally oriented perpendicular
to the substrate surface, for example a skin surface, when the
device is handled. However, it is also possible, in a particularly
advantageous manner, for the outlet nozzle to have a nozzle outlet
which runs at an angle to the housing axis, the angle preferably
being greater than 45.degree.. It is particularly advantageous if
the nozzle outlet runs in a direction which is in the range of more
than 75.degree. up to or more than a right angle, i.e. the outlet
direction runs essentially in a plane normal to the housing axis of
the housing. When the orientation of the housing is substantially
constant, i.e. approximately perpendicular to the substrate
surface, this embodiment of the invention allows the liquid to be
injected into the substrate substantially parallel to the substrate
surface and closely below it, which is particularly easy to
achieve, when the substrate, such as the skin of a human being, is
pliable in its upper layer and can be depressed a certain distance
in a trough-like manner by means of the device so that the nozzle
outlet is then located in this trough-like forming depression below
the level of the adjacent substrate and then the liquid can be
injected substantially parallel to the substrate surface below this
substrate surface. In particular for such an outlet nozzle, it or
the front end of the housing may be provided with a depth indicator
or a depth stop so that the liquid can be injected to the exact
depth required below the substrate surface.
[0033] In a particularly advantageous embodiment of the invention,
it is provided that the liquid container with the liquid contained
therein together with an ejector plunger of the ejector device is
movably accommodated in the housing or an acceleration section
provided in the housing, respectively, and that the housing has at
its front outlet end a stop for the liquid container. This
embodiment has the advantage that the liquid container together
with the liquid contained therein is first accelerated together
with the ejector device in the housing before the liquid is ejected
from its container through the outlet nozzle. This limits the
pressure increase (static pressure increase) in the liquid when
actuating the ejector device to eject the liquid by first imposing
a dynamic pressure component on the liquid. Especially in the case
of pressure-sensitive liquids, this can reduce or completely avoid
the risk of damage. In order to slow down the (static) pressure
increase in the liquid when the liquid container hits the stop, it
is advantageous when a stop damper, for example an elastomeric
buffer element, is provided between the stop and the liquid
container.
[0034] The invention proposes a liquid container for use in
carrying out the method according to the invention and/or in the
device according to the invention, which is characterized by at
least one accommodating space for liquid, a liquid outlet and a
shock inducer element for inducing an impulse shock into the liquid
accommodated in the accommodating space. The shock inducer element,
which in general can be any kind of means or design of the liquid
container, which makes it possible to introduce a pressure shock
(impulse shock) into the liquid accommodated in the liquid
container, can be acted upon by an actuating means, in particular
the already mentioned ejector plunger, of the ejector device
provided for this purpose, which actuating means is accelerated to
high velocity after the device is triggered. When the actuating
means hits the shock element of the liquid container, or when the
liquid container hits the stop provided for this purpose in the
housing in the case of the embodiment in which the actuating means
is accelerated together with the liquid contained therein and the
ejector plunger jointly to a velocity, the shock impulse inherent
in the actuating means due to its mass and its high velocity is
transferred to the liquid contained in the container and causes a
sudden, very large increase of pressure (pressure surge) in the
liquid, which results in a first partial quantity of the liquid
contained in the container being pressed through the outlet nozzle
at a correspondingly high pressure, wherein preferably a rotational
movement is applied to the liquid as it passes through the nozzle
passage. The first partial quantity discharged as a result of the
pressure shock thus exits the outlet nozzle corresponding to the
very high pressure rapidly generated in the liquid at very high
velocity as a liquid jet (preferably) rotating around its jet axis
and penetrates the substrate without any further significant
resistance. In the substrate, the rotating liquid jet creates an
injection channel which is open at the substrate surface and
reaches an injection depth. This achieved depth depends essentially
on the jet thickness, which is essentially determined by the
cross-section of the outlet nozzle through which the liquid leaves
the device, and on the jet velocity at which the first partial
quantity impinges on the substrate surface. This velocity, in turn,
is (among others) a function of the pressure that is actually
attained for only a very short time as a result of the impulse
shock in the liquid. By varying the velocity of the actuating means
(ejector plunger) and thus the amount of the impulse given to it,
the injection or penetration depth into the substrate can be
adjusted. Surprisingly, it has been found that a second partial
quantity of liquid subsequently introduced into the substrate
through the injection channel previously created by means of the
first partial quantity, which second partial quantity is then
usually ejected through the outlet nozzle at significantly lower
pressure and injected into the substrate at a correspondingly low
velocity, also reaches the end of the previously created injection
channel, i.e. the penetration depth, and is then distributed in
this depth essentially evenly around the channel. A second partial
quantity of liquid can thus be injected to the desired depth in the
manner of a liquid depot. For carrying out such a two- or
multi-stage injection, an ejector device with electromagnetic drive
for the ejector plunger has proved particularly suitable. The
ejector plunger is first accelerated by the electromagnetic drive
in an acceleration section in front of the liquid container (or
together with it) to the desired high plunger velocity and then in
a very brief time interval, preferably abruptly, decelerated
(optionally together with the liquid container) to generate the
impulse shock in the liquid, whereupon the pressure in the liquid
suddenly rises to a very high value as described and the first
partial quantity of liquid is ejected from the container and leaves
the outlet nozzle at a very high velocity, preferably under
rotation, i.e. a helical movement. For ejecting a second (and
possible further) partial quantity(ies) into the injection channel
thus created by means of the first partial quantity, the ejector
plunger is inserted by means of the electromagnetic drive in the
manner of a syringe plunger of an injection syringe with an
ejection force at the shock inducer element into the volume of the
liquid contained in the container and thereby expels the liquid
through the outlet nozzle, from where it enters the injection
channel previously shot into the substrate by the first partial
quantity.
[0035] The ejector device with electromagnetic drive, which has its
independent inventive merit and which is of course also suitable
for methods and devices in which the liquid accelerated into the
form of a thin jet for needleless injection is not set in rotation
or helical movement, not only allows the above-mentioned step-wise
injection with two or more partial quantities of liquid. It is also
ideally suited for placing a series of injections in a short time
sequence at different, preferably immediately adjacent points in
the substrate. For this purpose, the ejector plunger is moved back
into its initial position immediately after the generation of the
impulse shock in the liquid supply, preferably by briefly reversing
the direction of the current in the coil, and is thus ready for a
further injection within a very short time, for which it is
accelerated again in the injection direction by means of the
electromagnetic coil and again generates a pressure shock in the
liquid supply. A liquid container forming a cylinder space with a
liquid outlet provided on a side and a piston actuatable by the
ejector plunger, which piston is insertable into the cylinder space
in steps effected by the plunger hitting it, in order to always
eject a partial quantity of liquid from the liquid outlet, which
liquid then exits the device through the outlet nozzle, is
particularly suitable for carrying out such series injections. As
the piston is pushed increasingly deeply into the cylinder space of
the liquid container by the ejector plunger with each injection
step, the acceleration section available to the ejector plunger
between a rear, constant stop in the housing and its stop at the
front, defined by the piston, is step-wise increased. Since the
increase of the acceleration section with otherwise unchanged
general conditions, in particular constant electric current applied
to the electromagnetic drive, would result in an increasingly
greater velocity of the plunger when it hits the piston, the
pressure shock generated in the liquid and the resulting jet
velocity and penetration depth would then also increase, means are
preferably provided for adapting the velocity of the plunger when
it hits the piston, which means make it possible, irrespective of
the position of the piston in the liquid container, to repeatedly
generate in the latter at least approximately equally strong
pressure pulses, so that the injections generated in series each
penetrate the substrate to the same depth. The device according to
the invention is thus advantageously suited for injecting under
wrinkles in the skin of a patient or for producing tattoos which
can be produced needle-free with the invention.
[0036] It is also possible that the electromagnet and/or the energy
storage (battery/accumulator) intended for its operation are
located on the moving part of the ejector device, i.e. in
particular the ejector plunger, and can be removed from the housing
together with it, e.g. in order to clean and/or sterilize the
housing before using the device again.
[0037] Further areas of applicability will become apparent from the
description provided herein. The description and specific examples
in this summary are intended for purposes of illustration only and
are not intended to limit the scope of the present disclosure.
DRAWINGS
[0038] The drawings described herein are for illustrative purposes
only of selected embodiments and not all possible implementations,
and are not intended to limit the scope of the present
disclosure.
[0039] Further features and advantages of the invention result from
the following description and figure, in which preferred
embodiments of the invention are presented and explained in more
detail by means of examples. These show:
[0040] FIG. 1 a general representation of an injection device
according to the invention in perspective view;
[0041] FIG. 2a-c the handling part of the injection device
according to FIG. 1 in longitudinal section in different operating
positions of the ejector device;
[0042] FIG. 3 the ejector device with a first version of an outlet
nozzle used in the invention, in longitudinal section;
[0043] FIG. 4 a second embodiment of an outlet nozzle for use with
the device according to the invention in section;
[0044] FIG. 5 a third embodiment of an outlet nozzle for use with
the device according to the invention in section;
[0045] FIG. 6 a fourth embodiment of an outlet nozzle for use with
the device according to the invention in section;
[0046] FIG. 7 the orifice plates of the orifice plate stack used in
the embodiment according to FIG. 6 in a perspective, expanded
representation (exploded view); and
[0047] FIG. 8 a fifth embodiment of an outlet nozzle for use with
the device according to the invention in section.
DETAILED DESCRIPTION
[0048] Example embodiments will now be described more fully with
reference to the accompanying drawings.
[0049] In FIG. 1, 10 refers to an injection device as a whole
according to the invention, which has a handling part 11, which is
connected via a cable connection 12 to an external power supply 13,
a battery pack in the embodiment shown.
[0050] The handling part 11 of the injection device 10 can be
conveniently handled by its user with a single hand. The more
detailed structure of the handling part 11 is clearly visible in
the sectional view according to FIG. 2a to c. Accordingly, it has a
housing 14 which is provided with a recess 15 on its outer
circumference in which a magnetic coil 16 is accommodated. The
magnetic coil 16 is protected by a circumferential cover 17.
[0051] The magnetic coil 16 is part of an ejector device referred
to as 18 in its entirety, which further comprises an ejector tube
19 made of plastic material inserted into the housing and passing
through it essentially from its rear end (right in the figure) to
the front (left) outlet end, and an ejector plunger 20 guided
therein in a longitudinally displaceable manner, which in the
embodiment shown has a rear section 21 and a front section 22.
While the rear section with a larger diameter is adapted to the
internal cross-section of the ejector tube 19 and can slide in it
with as little play and friction as possible, the front section 22
has a smaller diameter. It forms a pressure piece 23 which can be
inserted or is insertable from behind into a cylindrical liquid
container 24 in the form of a liquid round or cartridge containing
a liquid 25 to be injected into a substrate, for example into or
under the skin of a human or animal. This liquid container 24,
similar to the rear section 21 of the ejector plunger 20, is
accommodated in the ejector tube 19 substantially without play, so
that it can also slide easily in the latter. At the rear (i.e. on
the right in the figure), the liquid container 24 is closed by a
piston 26, which holds the liquid 25 in the container 24 and is
pushed into the cylinder space 27 defined by the container 24 to
such an extent that the pressure piece 23 also fits a little into
this cylinder space at its rear. On its left outlet side, as shown
in the figure, the liquid container 24 is closed with a membrane
28.
[0052] The ejector tube 19 is fitted with a cap 29 at its front
end, left-hand side in FIG. 2, which has a central opening in which
a piercing cannula 30 projecting inwards towards the liquid
container 24 is accommodated. An elastic buffer element 31
surrounding the piercing cannula 30 is arranged inside the cap.
[0053] The piercing cannula 30 protrudes with its outlet side end
opposite its piercing tip 32 somewhat beyond the cap 30 and thus
forms a centering for an outlet nozzle 33, which is fitted onto
this outlet side end of the cannula 31 and fixed to the housing 14
by means of a union nut 34.
[0054] In order to prepare the device for use, the ejector plunger
20 with its front section 22, which forms the pressure piece 23, is
first inserted from behind into the cartridge-like liquid container
24, wherein the front side of the pressure piece 23 contacts the
piston 26 in the cylindrical opening of the liquid container. This
assembly of liquid cartridge and ejector plunger can then be
inserted with the membrane 28 in front, which closes the liquid
cartridge at the front, from behind into the ejector tube 19 in the
housing 16, for which purpose a cover cap 35 arranged at the rear
of the housing can be opened. After closing the cover cap the
device is ready for operation. This operating state is shown in
FIG. 2a.
[0055] Based on the FIGS. 2a to 2c, the operation of the device
according to the invention can be easily understood during
injection: FIG. 2a shows the initial position of the ejector
device, in which the rear section 21 of the ejector plunger 20 is
in the rearmost position (in the figure on the right) (rear end
position). The free space in the ejector tube 19 which extends in
this position of the ejector plunger and the liquid container
placed on the front of the ejector plunger up to the end cap 29
forms an acceleration section S, over the length of which the
assembly consisting of plunger and liquid container 24 can be
accelerated. In order to trigger an injection from the position
shown in FIG. 2a, the magnetic coil 16 is supplied with electric
energy from the battery pack 13 and thereby accelerates the ejector
plunger 20 with the liquid cartridge 24 attached to the front of it
over the acceleration section S in a direction of movement towards
the outlet nozzle (to the left in the figure). The accelerated
assembly reaches a very high velocity in a very short time, which
in practice can be over 500 m/s, and even over 800 m/s with a
suitably longer acceleration section. The liquid container 24 with
the liquid 25 contained in it first follows this movement until it
is decelerated by the buffer element 31, which is compressed
between the front cap 29 of the ejector tube 19 and the assembly of
ejector plunger 20 and liquid container 24 moved at high velocity
by the magnetic coil 16 towards the outlet nozzle 33. The main
purpose of the buffer element 31 is to prevent the liquid container
striking against the front cap 29 from jumping back from it. The
position of the ejector device in this operating state is shown in
FIG. 2b.
[0056] As is only schematically indicated by dotted lines in the
illustration according to FIG. 2a, the free space 36, which is
present inside the ejector tube 19 between its front cap 29 and the
front end of the liquid container 24 closed by the membrane, is
connected to the space 38 behind the rear plunger end 21 by means
of an overflow line 37. Through the overflow line, air can be
displaced from the front free space 36 or actually actively sucked
out by the negative pressure in space 38 which forms behind the
plunger during its forward movement, thus ensuring that the ejector
plunger 20 with the liquid container 24 is not slowed down due to
increased air resistance. In the practical implementation of this
feature, the overflow line can be integrated into the wall of the
housing so that it is actually not noticeable from the outside.
[0057] As soon as the piercing tip 32 of the piercing cannula 30
pierces the membrane 28 provided at the front end of the liquid
container 24, the liquid 25 contained in the container can emerge
from the front end of the container and pass through the cannula 31
into the outlet nozzle 33. Since at the moment of piercing, the
liquid container 24 with the liquid 25 contained in it is still
moving at high velocity and this movement stops very abruptly as
soon as the buffer element 29 is compressed as much as possible,
there is a brief strong pressure increase in the liquid volume
contained in container 24 (pressure shock), because the ejector
plunger 20 pressing on the rear of piston 26 in the liquid
container 24 with its pressure piece 23 is decelerated just as
suddenly and transmits its own dynamic energy as an impulse shock
into the initially co-accelerated liquid, which triggers the strong
pressure increase in the latter. Due to this briefly, very high
pressure in the liquid, a first partial quantity of the liquid is
pushed at a correspondingly high pressure through the cannula and
the subsequent outlet nozzle 33 and exits the outlet nozzle at the
outlet side of the outlet nozzle at a high orifice velocity
corresponding to the high static pressure, ambient pressure being
imposed on the liquid at the outlet side of the outlet nozzle and
the inherent pressure energy being converted into kinetic energy
(velocity). In practice, the outlet nozzle used, which is
preferably designed as described below, can have a passage 36 for
liquid 25 with a diameter of 80 to 300 .mu.m, so that the first
partial quantity of liquid ejected as a result of the impulse shock
impinges as a very fine liquid jet with a correspondingly small
cross-section on the substrate at a very high velocity. The exit
velocity of the liquid as a result of the pressure shock can easily
reach 1000 m/s. With this extremely fast and thin liquid jet, an
injection channel is created (shot) in the substrate to a depth
that depends on the jet velocity and its diameter and thus
ultimately on the strength of the impulse shock generated by the
ejector plunger in the liquid supply.
[0058] According to the invention, it is possible to inject the
entire amount of liquid contained in the liquid container or,
anyway, a second partial quantity of liquid in addition to the
first partial quantity injected forming an injection channel, as
explained above, into the substrate at this injection point. For
this purpose, the magnetic coil 16 can continue to be powered after
reaching the front end position of the liquid container 24 (FIG.
2b). This causes the ejector plunger 20 with its front section 22
(pressure piece 23) to be pressed further from behind against the
piston 26 in the liquid container so that at least a part of the
liquid (second partial quantity) still remaining in the container
after the pressure shock has decayed is pressed through the cannula
31 as with a conventional syringe and then ejected through the
outlet nozzle 33. Surprisingly, it has been found that despite the
significantly lower pressure with which the second partial quantity
is then ejected and the lower exit speed of the second partial
quantity liquid from the outlet nozzle resulting therefrom, also
the second partial quantity reliably and completely penetrates into
the injection channel created in the substrate previously by means
of the first partial quantity and thus reaches into the substrate,
i.e. in the embodiment into or under the skin. This generally leads
to a depot formation at the end of the injection channel, i.e. the
second partial quantity of liquid is distributed substantially
evenly in the tissue in a spherical shape around the end of the
injection channel. The injection can be continued until plunger 26
is fully inserted from pressure piece 23 to the front end of the
liquid container (FIG. 2c).
[0059] If desired, a sequence of more or less closely positioned
injections of comparatively small amounts of liquid can be made at
short intervals with the device. For this purpose, the ejector
plunger 20 is pulled back into its initial position (i.e. to the
right in the figure) by suitable control (changing the direction of
electrical current) of the magnetic coil 16 directly after
generating a pulse shock in the liquid contained in the container.
Since the liquid container 24 for the embodiment described here is
already open from the piercing tip 32 of the cannula 30 at the
membrane after the very first injection carried out as described
above, in this mode of operation it remains expediently in its
left-hand end position as shown in the figure according to FIG. 2c,
which can be ensured by a suitable retaining element not shown. For
example, for this purpose, a locking bar pretensioned radially
inwards transversely to the longitudinal axis of the ejector tube
19 by means of a spring can be accommodated in a recess in the
ejector tube, which locking bar, after the liquid cartridge has
passed after the first injection has been triggered, moves radially
inwards under the spring pressure, gripping behind the rear edge
(in the figure at the right end of the liquid container) of the
liquid container and thus preventing it from moving back again. The
ejector plunger 20, which has been pulled back again by momentarily
reversing the polarity of the magnetic coil, can be held in its
retracted position by means of a small permanent magnet or an
electromagnet on the rear cover cap 35 of the housing so that it
does not drop again unintentionally and/or prematurely against the
shock inducer element (piston 26) on the liquid container solely
due to its own weight. The ejector plunger can then, optionally by
overcoming the magnetic holding force of the aforementioned (not
shown) permanent magnet or electromagnet, be accelerated again to
high velocity via the acceleration section lying in front of it,
wherein it slides to the end of its movement with the front
pressure piece back into the cylinder space at the rear end of the
liquid container and there hits the piston 26 and thus again
generates a pressure shock for ejecting a further (small) partial
quantity of liquid. The repeated triggering of the electromagnet
and the resulting ejection of liquid from the device (after its
repositioning at the next, desired injection point) can be done
manually, i.e. by actuating a (not shown) triggering mechanism, or
automatically at pre-determined time intervals, which can also be
very short, for example when using the device as a tattoo machine.
An operation of the device with a triggering frequency in the range
of 35 to 200 Hz is easily possible with suitable dimensioning of
the plunger and the acceleration section.
[0060] In FIG. 3, a first preferred embodiment of the outlet nozzle
33 to be used is shown in its mounted state on the housing of the
device according to the invention. It can be seen that this outlet
nozzle 33 has a central passage 39, running coaxially to the
cannula 30, for the liquid 25 to be injected, which passage has on
its passage wall 40 at least one screw-shaped or helical fluid
channel 41, which extends from the nozzle inlet 42 on the side of
the cannula 30 to the nozzle outlet 43, from which the liquid 25
exits for injection. This helical fluid channel 41 causes a swirl
or rotational movement to be imposed on the liquid flowing through
the outlet nozzle 33 so that the liquid jet 44 is set in rotation
around its jet axis 45 when it exits the nozzle and thus impinges
on the substrate 46, in the embodiment the skin of a human or
animal, as a rotating liquid jet.
[0061] The superposition of the translatory movement of the liquid
with the rotation imposed on it causes the liquid jet 44 to
practically screw or drill itself into the substrate 46 when it
impinges on the substrate, wherein the helical movement of the
liquid apparently holds the jet together, so that when the liquid
impinges on the surface of the skin or substrate, it does not
mushroom and splash off sideways, but rather enters the substrate
with as little loss as possible and creates an injection channel 47
with a depth T, which depends essentially on the nature of the
substrate, the velocity of the liquid jet in the axial direction
and its cross-section. In the embodiment shown, the passage 39 in
the outlet nozzle has a diameter of approx. 80 to 100 .mu.m on the
outlet side and the (first) partial flow exiting this passage as a
result of the pressure shock in the liquid supply exits the nozzle
at a velocity in the order of 100 to 1000 m/s. The depth of the
resulting injection channel in (human or animal) tissue can thus be
adjusted between a few millimetres and a few centimetres.
[0062] FIG. 4 shows a further embodiment of an outlet nozzle
according to the invention, wherein corresponding features are
provided with the same reference signs as for the first embodiment.
The outlet nozzle 33 shown in FIG. 4 is fixed to the housing by
means of a union nut 34a, which also forms a spacer or depth gauge.
The outlet nozzle shown in FIG. 4 can be pressed a little bit into
the substrate 46, namely from its upper side 48 into the skin of a
patient, so that it forms a trough-like depression 49 therein. A
radially outwardly projecting ring area 50 on the union nut 34a
limits the depth of depression of the nozzle or indicates when a
desired depth has been reached, which is the case when the outer
edge of the ring area 50 also comes into contact with the skin
surface 48. The outlet nozzle 33 has a passage 39 with an
approximately cup-shaped nozzle chamber 51 on the inlet side, on
the wall of which two (or more) fluid channels 41 are formed, which
wrap around each other helically in the manner of a double (or
multiple) helix and which, as described, impose the swirl (spiral
movement) according to the invention on the liquid flowing through
the nozzle. The nozzle has two (or also several) laterally e.g.
radially outwardly open nozzle outlets 43, through which, in
contrast to the first embodiment of the device, jets of liquid 44
do not leave the nozzle coaxially to its longitudinal direction,
but in directions which are essentially perpendicular to the
longitudinal axis of the device or--in the embodiment shown--even
an angle .alpha., which can be slightly greater than 90.degree.. In
this way it is easily possible to inject the liquid not
perpendicularly to the substrate surface, but to distribute it
under the uppermost skin layer 52 essentially parallel to the
surface in the substrate.
[0063] The embodiment of an outlet nozzle 33 shown in FIG. 5
largely corresponds to that shown in FIG. 3. However, the passage
39 here does not have a constant cross-section over its entire
length, but on the inlet side it initially has a converging section
53, whose cross-section decreases in the flow direction 54 of the
liquid 25 ejected through the nozzle, and then continues into a
section of constant cross-section 55. In both sections 53 and 55,
helically spiraling fluid channels 41 are provided on their walls,
in the embodiment shown two channels, which are arranged in the
manner of a double helix. The converging section firstly ensures an
acceleration of the fluid passing from the fluid container into the
nozzle.
[0064] FIG. 6 shows an embodiment of the outlet nozzle for the
invention, in which the or a fluid channel 41 extends through the
outlet nozzle 33 in the form of a helical pipe 56 from the inlet
side 42 to the outlet side 43 of the outlet nozzle 33. The
arrangement is such that the pipe 56 has a helical radius R
decreasing from the inlet side 42 to the outlet side 43. Thereby a
cyclone effect is achieved, i.e. an acceleration of the rotational
velocity of the liquid flowing through the pipe helix 56 around
itself, so that the liquid rotates around itself at high velocity
when it exits the nozzle outlet.
[0065] In the embodiment shown in FIGS. 7 and 8, the outlet nozzle
33 has a plurality of orifice plates 58 which are arranged one
behind the other in the direction of passage 54 of the liquid in
the form of an orifice plate stack 57, which orifice plates each
have a slot opening 59 extending over a part of the plate diameter
d, the slot openings 59 of successive orifice plates 58 in the
orifice plate stack 57 being arranged offset to one another in the
circumferential direction by an angular amount .beta.. The amount
of this angular offset .beta. in the circumferential direction is
smaller at the radially outer ends of the slot openings 59 than the
width of the slot openings. This results in a spiral staircase-like
fluid channel 41 with a central passage opening. The embodiment
with the stacked orifice plates can be manufactured particularly
easily and cost-effectively, even having the smallest dimensions
with an aperture cross section in the micrometer range.
[0066] In the outlet nozzle 33 shown in FIG. 8, four fluid channels
41 are formed on the wall 40 of the passage 39 passing through it,
which run in a straight line parallel to the flow direction over
the length of the section with constant cross-section 55 and are
separated from each other by webs 60. In this embodiment, the
entire nozzle is rotatably mounted on the housing of the device and
can be driven by an electric motor using a coil. When it is set in
rotation during the ejection, the webs on the passage wall transfer
this rotational movement to the outer circumferential area of the
liquid jet flowing through the nozzle, thus imposing the rotational
movement according to the invention on the jet.
[0067] The foregoing description of the embodiments has been
provided for purposes of illustration and description. It is not
intended to be exhaustive or to limit the disclosure. Individual
elements or features of a particular embodiment are generally not
limited to that particular embodiment, but, where applicable, are
interchangeable and can be used in a selected embodiment, even if
not specifically shown or described. The same may also be varied in
many ways. Such variations are not to be regarded as a departure
from the disclosure, and all such modifications are intended to be
included within the scope of the disclosure.
* * * * *