Pressure wave device with dual valve means

Abstract

The present invention relates to a device for treatment using pressure waves. The device includes a projectile (8) guided along a path of motion, an applicator (6) at one end of the path of motion, and pneumatic means for applying pressure to the projectile (8) to cause it to move. The projectile (8) is configured to strike the applicator (6) to generate a pressure wave. The pneumatic means includes dual valve means (1, 2) for applying pressure to the projectile (8) toward the applicator (6) at a first activation time and in the opposite direction at a second activation time, and control means (54). The device is configured to maintain a separation time during the activation time and to control the impact velocity according to the separation time.

Description

[Technical Field]

[0001] The present invention relates to a device for treating the human or animal body using mechanical pressure waves generated by the impact of an accelerated projectile on an applicator. [Background technology]

[0002] This type of device has been known for some time and is increasingly being used. Mechanical pressure waves are used in the treatment of patients (human or animal) and are introduced by placing an applicator on the patient's body and are generated by the impact of an accelerated projectile with the applicator. The applicator does not necessarily have to be one piece, but may be made up of a number of separate parts and materials.

[0003] A proven and frequently described technique for accelerating projectiles is pneumatic: pneumatic overpressure is introduced by applying pressure to a volume on one side of the projectile that is movable along its path of motion, for example in a pipe segment.

[0004] In the prior art, a switching valve is used for this purpose, connected to an air pressure supply, in particular a compressor with an adjustable output pressure, the pulses of which accelerate the projectile from the end of the path of motion distal to the applicator towards the applicator, and when the proximal end of the path of motion is reached, i.e. when the applicator is impacted, the air pressure application is switched off.

[0005] In the prior art, the return movement is carried out with the aid of an opposing pressure chamber, i.e., a storage volume, into which the projectile, having moved to a certain extent towards the applicator, displaces the air located in front of it, thereby essentially pumping up the storage volume.

[0006] In U.S. Pat. No. 5,623,669, which was revoked in opposition proceedings for lack of reproducibility, a target pressure limit in the opposing pressure chamber is described in addition to controlling the opening time of the switching valve with respect to acceleration, which is not described in detail. Furthermore, the patent mentions the use of a second switching valve to return the projectile to the distal starting position after application by the first switching valve. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] European Patent Publication EP2181730B1 Summary of the Invention

[0008] The present invention is based on the object of realizing a device of the above-mentioned type with pneumatic means for projectile movement, on the basis of which the device is improved with regard to the forward and backward movement of the projectile.

[0009] To achieve this object, a device is proposed according to claim 1. Preferred configurations are the subject of the dependent claims.

[0010] That is, the device according to the present invention has, as part of its pneumatic means, a double valve means, e.g., a combination of a first valve and a second valve, for directing the projectile in both directions, i.e., toward the applicator and away from the applicator in the opposite direction. This is, for example, repeated sequentially and repeatedly. The time phase during which air pressure is applied to the projectile to move in the forward direction, i.e., the activation phase of the first valve, for example, is hereinafter referred to as the first activation time, and the time phase during which the projectile is urged in the opposite direction is hereinafter referred to as the second activation time. According to the present invention, the device can be configured (i.e., in particular, the control means in the device can be configured) so that the second activation time begins only after the first activation time has ended and the separation time has elapsed. Therefore, there is a non-zero separation time between the two valve opening times.

[0011] The same is (alternatively or additionally) true in the reverse order, ie with respect to the separation time after the second activation time ends and before the first activation time begins.

[0012] For example, the first activation time can end well before the impact of the projectile on the applicator, and the second activation time can begin immediately after impact. Then, instead of the entire available time between the projectile's initiation of motion and its impact on the applicator, only a first portion of it is used for acceleration in the presence of an acceleration pressure. For example, the impact velocity of the projectile can be reduced in this way without reducing the acceleration air pressure. This may be desirable, for example, to achieve a higher return value (with the aid of the second activation time) that is as fast as possible than is momentarily required for forward acceleration.

[0013] As a result, in this manner, the impact velocity can be controlled by the controller to be accurate even independent of pressure changes (eg, at constant pressure).

[0014] It can also be advantageous to be able to reduce the impact velocity of the projectile upon impact without reducing the air pressure. For example, on the one hand, a particularly fast return of the projectile (due to the second valve opening time), i.e. a relatively high operating frequency, may be desired, but on the other hand, for therapeutic reasons or because of patient hyperalgesia, an excessively high strength (i.e. impact velocity) is not intended. Alternatively, for other reasons, it may be desirable to reactivate immediately before or after with a higher impact velocity or not reduce the pressure.

[0015] Furthermore, the separation time can be completely or partially after the impact in time, and a premature return movement or a high speed at the end of the return movement can be prevented, for example, by a delayed start of the second activation time after the impact, without reducing the acceleration pressure (for the forward direction). In this situation, it should also be taken into account that the impact itself already results in a certain acceleration of the projectile in the reverse direction, according to the law of conservation of momentum.

[0016] Of course, both aspects can be combined, i.e. a portion of the separation time before a collision and a portion of the separation time after another collision.

[0017] In the examples so far, the separation time has been considered to occur after the first valve opening time (adjacent to the separation time) and before the subsequent second valve opening time. However, additionally or alternatively, the separation time may be varied between the preceding (adjacent) second valve opening time and the subsequent first valve opening time. For example, such a separation time may be associated with a delayed start (and change due to the delay) of the first valve opening time during forward acceleration. Thus, the projectile's motion may initially begin due to a "recoil" at the distal end of its motion path, i.e., due to residual momentum of the projectile after impact with that portion of the device. This residual momentum allows the projectile to move forward immediately thereafter, but it is additionally accelerated at the beginning of the first valve opening time. Thus, there may also be a portion of the forward motion path that does not involve pneumatic acceleration by the first valve (of course, in this example, the first valve opening time may end before impact with the applicator).

[0018] A further example relates to such a separation time, or a portion of such a separation time, at the end of the return movement, before reaching the distal end of the movement path. Again, variations in separation time can (indirectly) affect the velocity of the projectile upon subsequent impact with the applicator, particularly since the "recoil" at the distal end can pre-introduce different residual momentum at the beginning of the forward movement depending on the projectile velocity when that end is reached.

[0019] A further example relates to varying the two separation times, for example, complementary to each other. In the simplest case, for a fixed valve opening time and a given repetition frequency, one of the two separation times can be lengthened at the expense of the other.

[0020] For the avoidance of doubt, it is made clear that the term valve open time as used herein primarily includes both duration and position relative to a reference point in time, and in particular relative to each other valve open time. Thus, the term includes the start and end of a valve open time and the interval therebetween, unless expressly referred to below as duration only or start or end only.

[0021] The combination of the two switching valves discussed above represents a possibility of a double valve means provided in accordance with the present invention. In this variant, the two valves may be controlled (preferably independently of each other) by the control means. Alternatively, however, one and the same valve, referred to herein as a "combination valve," may be used, which, depending on the control by the control means, has at least two switching states: a first switching state for applying air pressure to the projectile in a direction towards the applicator, and a second switching state for applying air pressure to the projectile in the opposite direction. While the combination valve is in the first switching state, there is a first valve opening time, and correspondingly, in the second switching state, there is a second valve opening time.

[0022] In these two switching states, the pneumatic connection applied in each of the other switching states is preferably ventilated by a combination valve, so that, for example, during forward movement, ambient pressure prevails approximately on the side of the projectile proximal to the applicator, and there is no dynamic pressure increasing from impact to impact, in contrast to conventional procedures with opposing pressure chambers.

[0023] Even when two separate valves are used, at least one of the two valves is preferably a "two-way valve" that provides ventilation as appropriate but is not switched for the application of air pressure. However, additional switching states are not excluded and the valve is not necessarily limited to strictly two switching states.

[0024] Ventilation is also intended to mean a pneumatically highly conductive connection to the outside atmosphere or a reference pressure volume substantially corresponding thereto, and therefore is not a matter of deliberate retardation of the outflow of gas under overpressure in the sense of a throttle.

[0025] As an alternative to ventilation via a combination valve or the two-way valve mentioned above, the device can also have, for example, some kind of air pressure leak, and in this way or in a substantially gradual manner, throttle ventilation itself can take place in the absence of applied air pressure, although this option is less preferred.

[0026] Preferably, the first activation time is variable in at least two control states with different separation times, i.e., for example, with a fixed portion (including zero) of the separation time after applicator impact. In the simplest case, there are only two control states in this example, but preferably there are more, and of course a zero separation time can also be in one control state, provided there is at least one other separation time that is not zero.

[0027] Of course, the second activation time may also be variable, but may also be completely constant in duration and / or start and end relative to the reference, for example in the case of the fixed portion of the separation time after applicator impact just described, which is particularly preferred.

[0028] It has been initially described that devices of the type considered here typically perform multiple acceleration, impact, and return transport processes of a projectile. In the prior art, the corresponding repetition frequency of such periodic actuations is regularly adjustable. In the present case, too, repetitive (not necessarily periodic) actuations and the corresponding design of the device are preferably considered, and the corresponding sequence does not necessarily have to begin with a forward motion.

[0029] For example, such a sequence may begin with a first air pressure pulse for projectile movement in a reverse direction to a position distal to the applicator to establish a defined initial condition. Essentially, a magnet at the distal end of the projectile's path of motion is known in the prior art, thereby immobilizing the projectile. However, such immobilization may of course be dispensed with, as the projectile may be released from this immobilization as a result of impact.

[0030] In other cases, the description does not necessarily relate to the individual motion steps within such a motion sequence. Operating conditions, as described in more detail, may change during the sequence, so that the separation times described may not exist at all for some of the motion steps within the sequence, for example.

[0031] The details of the present invention have been described above with respect to the separation time between the first and second activation times. According to a further preferred configuration, the device, particularly the control means, may be configured such that in certain further control states, such separation time does not exist, but instead there is an overlap time (non-zero, thus zero separation time) between the first and second activation times, or vice versa. Such an overlap time in certain control states (when other control states with separation times exist) provides an additional degree of freedom. This degree of freedom can be used, for example, to control the impact velocity of the projectile impacting the applicator by varying the overlap time. Specifically, in this example, if the second valve opening period begins before impact during the first valve opening period, in addition to the air pressure accelerating the projectile in the forward direction, an opposing force acts on the projectile. In the simplest case, if approximately the same air pressure is used, this opposing force will be approximately equal in magnitude and can substantially cancel the acceleration. Depending on the length of the portion of the first valve open time prior to this time, the projectile may be accelerated to a higher or lower velocity, and then may maintain that velocity for, for example, the overlap time.

[0032] The opposite is also true: if, for example, the second valve opening time is not only used up to the maximum of returning the projectile completely to its starting position, but continues somewhat beyond this, but an overlap occurs as a result of the first activation time already beginning during the second activation time, then no significant force acts on the projectile again during this overlap time (in the simplest case). Thus, since forward acceleration due to air pressure begins only after the end of the overlap time, there may be phases (possibly already during and after the return movement) where there is no forward acceleration of the projectile due to air pressure.

[0033] One advantage may be that the impact velocity of the projectile can be controlled more accurately and / or more easily than in conventional comparative examples, which depend on the opening time of a (single) switching valve and, of course, on the available pressure. Existing switching valves actually have a fixed opening and closing time, i.e., they do not open and close instantaneously. This is especially true for the comparison between the closing time and the opening time of a (preferred) spring-loaded valve, where the opening process is performed magnetically, possibly using pneumatically assisted switching pressure, while the closing process is performed by a tensioned spring during opening. Experience has shown that there are design-related and age-related deviations, and that there can be different aging behaviors between the opening time and the closing time (here, the opening time in the sense of the opening process).

[0034] In the first above-mentioned case of the overlap time between the end of the first valve opening time and the beginning of the second valve opening time, the period relevant for projectile acceleration, i.e., the part of the first valve opening time before the overlap time, is caused by the time difference between the opening of the two valves (first valve first, second valve later). In the second above-mentioned case, the overlap time is the end of the second valve opening time. Here, since pneumatic projectile acceleration in the direction of the applicator is only necessary at the end of the overlap time, the remaining part of the first valve opening time after the overlap time, and therefore the difference between the closing of the two valves (second valve first, first valve later), is relevant. In both cases, this is the time difference between the movements of the same valves.

[0035] The inventors have found that in this way all of the above-mentioned age-related deviations become much less noticeable (i.e., for example, when closed times show a stronger ageing effect than open times), since their effects are at least partially compensated for by the formation of the above-mentioned differences.

[0036] In references from the prior art (all relevant expressions here being simplified), on the other hand, alternating modes of operation of the two above-mentioned valves are conceivable, which also correspond to the particularly high intensity of the projectile-applicator collision, i.e. the pressure wave, that is intended in this specification.

[0037] A further (alternative or additional) embodiment may be to operate at a relatively high air pressure, on the one hand, to achieve a rapid return and therefore also a high operating frequency, but on the other hand, not necessarily to use a high impact velocity corresponding to this high pressure (when such acceleration pressure is present throughout the forward movement). High intensities are not necessarily desired for therapeutic reasons, and would otherwise often lead to increased stress on the patient due to pain or other irritation.

[0038] In the first case described above, i.e., the overlap time at the end of the first activation time, the second activation time and the resulting overlap time are initiated during the projectile's forward movement. Thus, there is a final phase of this forward movement, during which pressure exists on both sides of the projectile. This leads to the possibilities already described. However, this feature is not essential; it can be advantageous to have pressure on both sides (only) after impact, i.e., during or even at the beginning of the projectile's return movement. For example, the supply pressure for the return movement, required for the projectile's acceleration, can be somewhat excessive, since it would be undesirable to allow the projectile to impact distally from the applicator with the same force acting on the applicator. In this sense, for example, the simultaneity of the first and second valve opening times at the beginning of the return movement can have a certain throttling effect on the return movement.

[0039] In the second case mentioned above, i.e., in the case of an overlap time at the end of the second activation time, a similar effect as described above can still be achieved for a portion of the overlap time during the return movement. The same applies to such synchronicity towards the end of the return movement, i.e., before the next acceleration process or event. In particular, the overlap time can be partly before and partly after the impact of the projectile on the applicator, or partly before and partly after reaching the point furthest from the applicator, as will be explained in more detail in connection with the exemplary embodiments.

[0040] Furthermore, in the first case of an overlap time at the end of the first activation time, it is preferable to end the first activation time during the second activation time, thus allowing the second activation time to typically continue beyond the first activation time. In particular, this naturally applies to the aforementioned return of the projectile. However, this feature is not essential. For example, the aforementioned compensation of the acceleration force due to the simultaneity of the first and second activation times (i.e., the application of air pressure to both sides of the projectile) can also occur entirely within the first activation time by a relatively short second activation time. The projectile can then be returned, for example, in a manner known in the prior art. Essentially, an additional second activation time (separate from the second activation time during the first activation time) can be used for the return.

[0041] Similarly, in the second case of the overlap time at the end of the second activation time, it is also preferable to allow the second activation time to end during the (next) first activation time, in particular to bring about the process of pneumatic acceleration of the projectile towards the applicator as already mentioned.

[0042] Preferably, one of the two activation times may be of a constant length in comparison between two control states with different overlap times (including zero in this case). In the case of an overlap time at the end of a first activation time, this preferably relates to that first activation time, and in other cases corresponds to a second activation time. This means that in these cases, the difference in overlap time is based on the different lengths by which each valve open time overlaps the other or on the temporal relationship between the two valve open times. Preferably, each other valve open time is of variable duration between two such control states with different overlap times (e.g., it may have the same end time for all or some of the control states, measured from the beginning of the earlier activation time).

[0043] Preferably, the portion of the overlap time during the projectile's forward motion before impact, i.e., from a distal position (relative to the applicator) to the applicator, is significantly greater than the portion or period attributable to the return motion. This preferably applies to all control states that have overlap times. Where some degree of mass damping of the return motion is not important, it may be preferable for the overlap time to exist exclusively during the forward motion.

[0044] In the simplest case, the pneumatic means may comprise a connection for supply from a pneumatic line network, for example in a hospital, or from a compressed gas cylinder. However, a pneumatic compressor is preferred, which makes the device according to the invention locally independent and more portable than a compressed gas cylinder. Pneumatic compressors are known for use with such devices. However, the invention provides a particular feature in that the supply pressure does not necessarily have to be changed in different control states with different impact velocities of the projectile. In other words, the compressor can operate at the same speed in such control states.

[0045] Naturally, this firstly simplifies the control of the compressor, especially if the compressor is essentially operated at the same rotational speed in the operating state. Furthermore, the compressor can be operated at or close to its maximum efficiency (in terms of rotational speed). Furthermore, it is possible to adapt the noise reduction measures, such as the damping equipment or the noise-damping housing of the compressor, to the vibration behavior of the compressor at the same rotational speed.

[0046] The particular design possibilities of the present invention are based on the ability to directly and rapidly influence the impact physics between the projectile and the applicator simply by varying the valve-open time or valve-open time duration, specifically the impact velocity and therefore the impulse associated with the impact. Compared to changes in supply pressure, this influence is particularly rapid, and in repeated actuation conditions, it is possible to essentially change the impact velocity / impulse of the combined forward and return motion from one impact event to the next. Such rapid and unrestricted influence or control is not possible with the prior art.

[0047] Typical impact velocities are in the range of 2 m / s to 30 m / s, although conditions may vary more slowly or not. Regarding impact physics, the impact impulse is particularly important, and for typical projectile masses, it may be 1 g to 10 g, preferably 2 g to 5 g, and thus may range from 2 gm / s to 300 gm / s. A range of 10 gm / s to 150 gm / s is preferred.

[0048] In a particular configuration, the device comprises a measuring means by which the passage of the projectile can be measured at a point in its path of movement. This measuring means can be connected to the control means. Thus, in this embodiment, for example, the passage of the projectile can be detected just before or approximately during impact with the applicator, so that the activation time can be appropriately timed to coincide with the end of the impact (particularly with respect to its start and end).

[0049] Such detection can be carried out, for example, optically, for example by means of a light barrier, but preferably inductively using a measuring coil, which can detect the projectile by means of its residual magnetism or purely inductively (by means of changes in leakage inductance).

[0050] The invention is explained in more detail below on the basis of exemplary embodiments, the individual features of which may also be required for the invention in different combinations within the scope of the claimed invention. [Brief explanation of the drawings]

[0051] [Figure 1] 1 shows a perspective view of a device according to the invention, with the central housing part removed for clarity; [Figure 2] 2 shows a longitudinal section of the device of FIG. 1 in a position mirrored relative to FIG. 1. [Figure 3] 1 shows a schematic diagram of a handpiece with the associated basic devices. [Figure 4] A series of schematic time charts (FIGS. 4a to 4f) are shown to illustrate the mode of operation. [Figure 5] 3 shows a schematic diagram of a combination valve to illustrate an alternative embodiment to that of FIGS. 1 and 2. FIG. [Figure 6] A series of schematic time charts (FIGS. 6a to 6e) are shown to explain further control states other than those of FIG. [Figure 7] 10 shows another schematic flow diagram for illustrating a cyclic mode of operation. [Figure 8] A repeating sequence of two different projectile velocity levels is shown in direct succession, with two pulses of slow velocity immediately following a pulse of fast velocity. [Figure 9] 9 shows a control sequence for controlling valves V1 and V2 according to a sequence of two different projectile velocity levels shown in FIG. 8. [Figure 10] The first 300 ms from the control sequence in Figure 10 are shown in higher resolution temporal detail. DETAILED DESCRIPTION OF THE INVENTION

[0052] Figure 1 shows a perspective view of the handpiece of a device according to the invention, with the pneumatic valves, namely valve 1 and valve 2, facing forward and to the left. The pneumatic supply connection 3 can be seen on the right, and two screw rings 4 and 5, each corrugated on the outside for ease of handling and intended to hold an applicator 6, described in more detail below, can be seen on the left. The applicator 6 has a surface facing the patient and can be seen further left in Figure 1, or as shown in Figure 2. It can also be made up of multiple parts.

[0053] A number of transverse pipes can be seen in the central region of the device in FIG. 1. The central pipe, labeled "7," contains and guides the projectile 8, visible in cross section in FIG. 2. Two parallel pneumatic connection pipelines 9 and 10 can be seen in front between the two valves 1 and 2. Pipeline 9 supplies pressure to the second valve 2, while pipeline 10, conversely, ventilates the second valve 2 through an outlet provided in the first valve 1. In this example, these pipes are surrounded by a housing cover 11, which is indicated in FIG. 1 by a line below the pipeline 10 and two lines above the projectile guide pipe 7. The housing cover 11 extends through the rear region in FIG. 1 and consists of only a portion of a circumference. At its axial edge, the cover 11 is designed in a manner similar to a flanging, with an inwardly rounded turnover (shown at the upper edge in FIG. 1) for easy gripping. Thus, the housing cover 11 can function as a handle during actual handling. A spacer 13 provides structural stability and mechanical connection between the two ends of the handpiece.

[0054] The flexible compressed air supply line (see "51" in Figure 3) from the air compressor to the device is not shown here and is to be connected to the already mentioned connection 3. Similarly, the electronic control line ("52" in Figure 3) from the external control device to valves 1 and 2 is not shown but can be designed in the same way as the compressed air supply line.

[0055] 2 shows a longitudinal section of the entire device along the imaginary central longitudinal axis of the cylindrical shape already described, which is simultaneously the central longitudinal axis of the projectile guide tube 7. In this projectile guide tube, the projectile 8, shown on the right side of FIG. 2, abuts against the applicator 6, which is held in a manner known per se by the already described screw rings 4, 5. In this case, the applicator 6 is axially elastically attached by a bellows-shaped elastomer ring 14 and pneumatically (gas-tightly) sealed by another elastomer ring 12. Alternatively, device designs for the applicator 6 and its holding and sealing, for example according to EP 2 529 679 (possibly independent of the cap shown therein) or EP 2 095 843 (possibly independent of the ceramic material described therein), are also possible and preferred.

[0056] 2 shows on the left an internal channel 21 connecting the pneumatic connection 3 to the first valve 1. The first valve 1 can appropriately switch the supply pressure applied to the pneumatic connection 3 to a radial channel 22 in response to a control. The radial channel 22 opens below the damper element 23 and is connected to the internal volume of the projectile guide tube 7. Through this channel 22, the projectile is thus set in motion at a first activation time in the direction of the applicator 6 and accelerated during the first activation time. Separately, the pneumatic supply pressure is sent to the second valve 2 via a channel 24 and a pipeline 10.

[0057] In a second, alternative switching position, the channel 22 and therefore the internal volume of the projectile guide tube 7 between its distal end (on the left in FIG. 2) and the projectile 8 is ventilated.

[0058] In the second valve 2, which is constructed essentially mirror-symmetrically to the first valve 1, the pneumatic supply pressure applied via the pipeline 10 can now pass radially upwards via the channel 25 into the volume surrounding the projectile guide tube 7 (visible in FIG. 2 as slots above and below the tube 7). The pressure proceeds from the connection of the channel 25 to the right, i.e., in the direction of the applicator 6, where it is connected to the internal volume of the projectile guide tube 7 between the applicator 6 and the end of the projectile guide tube 7 adjacent to it (apart from the presence of the projectile 8 shown in FIG. 2). Thus, via the channel 25, the pneumatic supply pressure can be switched to the internal volume of the projectile guide tube 7 between the applicator 6 and the projectile 8. However, in this example, as a result of the smaller effective opening cross-section of the projectile guide tube 7 than on the other side, the pneumatic connection is somewhat poorer, which results in earlier or more pronounced delays here at higher airflow rates (higher frequencies, higher pressures).

[0059] Alternatively, in the other switching position, the second valve 2 blocks the connection of the internal volume of the pipeline 10 to the second valve 2, and the channel 25 and therefore the internal volume of the projectile guide tube 7 to the right of the projectile 8 can be ventilated, i.e. pneumatically connected to the outside atmosphere via a highly conductive connection.

[0060] The two valves 1 and 2 can therefore apply air pressure to the projectile from both sides, i.e. independently of each other, and therefore simultaneously or alternately, or can ventilate the interior of the projectile guide tube 7 on both sides.

[0061] Reference numeral "30" in FIG. 2 denotes a ring-shaped permanent magnet at the end of the path of motion of the projectile 8 (which corresponds to the length of the projectile guide tube 7), the end distal to the applicator 6. This magnet 30 allows the projectile 8, made of a ferromagnetic material, to be easily fixed at this distal end of the path of motion. By applying pressure to one side by the valve 2, the projectile can be returned to this position and optionally additionally held there, especially at the beginning of actuation or in the case of non-ferromagnetic projectiles. In this regard, the permanent magnet 30 can also be optionally omitted, especially if recoil at this distal end of the path of motion is then possible even at low impact velocities of the projectile 8, as will be explained further below.

[0062] The reference numeral "31" indicates the point at which the passage of the projectile 8 through the corresponding point in its path of motion is detected by a measuring coil, which is located relatively close to the applicator 6. In the simplest case, the slight residual magnetism of the projectile 8 is used here, but of course, the change in inductance of the coil 31 can also be detected and evaluated using AC techniques. The collision of the projectile 8 with the applicator 6 can also be determined in an experimental setup by using microphones and motion sensors. Furthermore, the impact velocity of the projectile 8 can be determined in an experimental setup, for example, by using two light barriers placed directly in front of the applicator 6.

[0063] FIG. 3 shows a block diagram of the device shown in FIGS. 1 and 2, specifically indicated simply by the reference numeral "40" at the top right. This device 40 is a handheld, portable handpiece, as known from related devices according to the prior art. It is connected via two lines 51 and 52 to a base station 50, which includes a pneumatic compressor 53 and a control device 54. The compressor 53 is connected to the handheld device 40 via line 51, i.e., a pneumatic flexible hose line, and the control device 54 is connected via an electrical line 52 (which can optionally be integrated with line 51). Via this line, the control device can access and supply power to the two valves 1 and 2 already mentioned. Additionally, communication with the handpiece 40 can take place via line 52, especially if a control device or part of a control device is additionally provided therein.

[0064] Furthermore, the control device 54 also controls the compressor 53 in terms of its speed and of course switching it on and off, and together with the compressor 53 is powered by a mains power supply 55. Alternatively, pressure controls or control valves that affect the speed may be integrated into the compressor 53. The control device 54 is also connected to a display 56, which may be mounted on the base station 50 or may be provided separately from it. The base station 50 is operated via the touch-sensitive display 56 and / or an array of buttons not shown here.

[0065] The user can therefore control the functions of the device 40 on the basis of these buttons and in any case on the basis of the display 56, the control device 54 specifying in particular the opening and closing times and therefore also the opening periods of the two valves 1 and 2. Also, some of the tasks of the control device 54 can be integrated in the handpiece 40, in particular with regard to the control of valves 1 and 2.

[0066] For a basic understanding of the control of the two valves, reference may be made to the prior patent EP 2213273 B1. The specific example therein, particularly with regard to the dimensioning of the projectile guide tube and the projectile, corresponds substantially to the above description and to FIGS. 1 and 2, except for the presence of the second valve 2 and the absence of an opposing pressure chamber. Additionally, whereas in the cited example, a specific valve opening time of the single valve presupposes a specific pressure, in this example the projectile acceleration is variably achieved depending on the portion of the first valve opening time, even outside the overlap time and therefore at a constant pressure. In the following description, a pressure of 2 bar and a repetition frequency of 10 Hz may be assumed as an example. This results in the following list of values, together with the measured values: Projectile speed [m / s]: 4.7; 6.2; 8.1; 9.5; 10.3; 10.8 Valve 1 open time [ms]: 0; 0; 0; 0; 0; 0 Valve 1 closing time [ms]: 13;13;13;13;13;13 Valve 2 opening time [ms]: 13; 14; 15; 16; 17; 18 Valve 2 closing time [ms]: 21; 22; 23; 24; 25; 26 Impact time [ms]: 25.0; 24.6; 24.2; 23.9; 23.8; 23.7

[0067] Figure 4 shows, in the individual Figures 4a to 4f, a schematic time chart corresponding to the above list. There is a separation time between the control of valve 1 according to Figures 1 and 2, represented by a solid line below, and the control of valve 2, represented by a dashed line above. Overall, there is an activation pulse of valve 1, which accelerates the projectile 8, and after the first activation time has ended, it "flies" through a different part of its movement path without further air pressure application. During this movement phase, both sides of the tube interior are ventilated (not pressurized). In Figure 4a, this is the case after the second activation time.

[0068] After some time of deceleration by the second valve, a collision with the applicator as shown occurs, followed by a return movement of the projectile 8 due to this collision and due to the return air pressure pulse resulting from the (remaining) second activation time, thus returning the projectile 8 to its starting position again.

[0069] The length of the first activation time is unchanged. In this example, at least a portion of the second activation time precedes the collision, specifically all or most of the second activation time in the cases of Figures 4a-4e, and approximately half in the case of Figure 4f.

[0070] These examples illustrate further possibilities for controlling the velocity of the projectile 8 upon impact. In Fig. 4a, the projectile 8 is accelerated by air pressure through a first activation time, after which it is slowed by the opposing air pressure as a result of the start of a second activation time (upper dashed line). In the case of Fig. 4a, the delay time is in a ratio of 8:13 to the acceleration time, and since the same pressure levels can be assumed, the projectile 8 will impact the applicator 6 with the lowest velocity and will be returned to the starting point again after impact with the applicator 6 due to the elastic impact.

[0071] In Figures 4b and 4f, the separation time between the two activation times is longer, and therefore the portion of the second activation time prior to impact is progressively shorter, resulting in an increase in projectile velocity at impact despite an unchanged first activation time.

[0072] More precisely, Figures 4a-4f show the electrical control times, i.e., the output signals of the control device 54, of the two valves, Valve 1 and Valve 2. Valve 1 and Valve 2 are spring-assisted solenoid valves that open purely magnetically and close when the magnetic load is removed by the force of the spring tensioned during the process. The movement of the valve disc is therefore somewhat delayed relative to the exemplary control signal, specifically an estimated 4 ms when opening and 2 ms when closing.

[0073] In the case of so-called pilot valves with pneumatic assistance when opening, the situation would be qualitatively equivalent.

[0074] Naturally, in the case of another embodiment with a "combination valve", very similar relationships to those shown in Figures 4a to 4f can be created. Such a combination valve is shown diagrammatically in Figure 5. In this example, the symbol "K" denotes the combination valve, which accordingly replaces the two valves 1 and 2 according to Figures 1 and 2. Two lines V1, V2 are shown on the left and right, of which line V1 means, for example, a connection to the left-hand side (according to Figure 2) of the projectile guide tube 7 via channel 22 (analogous to the first valve 1). Similarly, the right-hand line V2 means, for example, a connection to the right-hand side of the projectile guide tube 7 via channel 25 (analogous to the second valve 2).

[0075] In FIG. 5, the upper line is indicated by the keyword "Pressure supply" and the symbol "1" (different from the symbol "1") for the first valve, and similarly the lower line connection is indicated by the keyword "Ambient pressure" and the symbol "0", i.e., the ventilation opening.

[0076] The combination valve K has a slide S, symbolically illustrated, which can be displaced vertically (in FIG. 5) between four different switching positions. In the topmost position, as illustrated in FIG. 5, line (connection) V1 is vented and line (connection) V2 is under pneumatic supply pressure, and vice versa in the third position from the top. In the second position from the top, which is just switched on activation, both line V1 and line V2 are vented. Finally, the bottommost position shows simultaneous pressurization of both line V1 and line V2 (see further below).

[0077] Therefore, instead of the two individual valves 1 and 2 according to the embodiment of Figures 1 and 2, it is possible to envisage a combined valve K constructed in the above-mentioned or similar manner, and the remaining explanations and in particular Figures 3 and 4 also apply.

[0078] The air compressor 53 (FIG. 3) operates at a predetermined fixed operating frequency with maximum efficiency so that the impact velocity of the projectile 8 can be controlled simply by switching the two valves 1 and 2. Furthermore, the air compressor may be able to be particularly effectively damped with respect to vibration and noise at the predetermined operating frequency.

[0079] Essentially, the controller 54 can vary the impact velocity and the time interval between the collision of the projectile 8 with the applicator 6 from one actuation to the next. This can affect the impact physics quite rapidly and quite variably, and is not particularly relevant for cyclic actuation.

[0080] Figure 6 shows a series of five individual schematic time charts (Figures 6a to 6e). In these time charts, the opening and closing process of the first valve 1 is represented by a curve marked "T1", and the opening and closing process of the second valve 2 is represented by a curve marked "T2". Thus, the increasing curve portions correspond to the first and second activation times, respectively.

[0081] By comparison, it can be seen that, on the horizontal (arbitrary) time axis, the first activation time begins at 0 ms and ends at 13 ms in all five control states. In contrast, the second activation time shifts in stages with respect to its onset, from 2.5 ms in FIG. 6a to 7 ms in FIG. 6e, while the second activation time ends at 18 ms in all five examples. Thus, there is an overlap in all control states, namely, from 3 ms to 13 ms in FIG. 6a to a further 7 ms to 13 ms in FIG. 6e. This overlap decreases in stages, i.e., corresponding to a gradually later onset of the second activation time. In this case, the application of air pressure by the second valve 2 to the return of the projectile 8 is effective in all five control states.

[0082] In the case illustrated in Figure 6, impact velocities of the projectile 8 against the applicator 6 of 10 m / s, 12 m / s, 14 m / s, 16 m / s, and 18 m / s are achieved at 4 bar pressure, in the order of Figures 6a through 6e. This corresponds to an impulse of 30 gm / s to 54 gm / s for a 3 g projectile mass. The opening time of valve 1 is a constant 13.0 ms. The closing time of the second valve also remains constant at 18 ms. The activation time of the second valve (again in the order of Figures 6a through 6e) varies from 15.4 ms to 15.0 ms, 14.3 ms, 13.0 ms, to 10.9 ms, resulting in overlap times of 10.4 ms, 10.0 ms, 9.3 ms, 8.0 ms, and finally 5.9 ms. Therefore, the activation time of the second valve 2 starts to be delayed by a period between 2.6 ms and 7.1 ms (increasing from top to bottom) compared to the first activation time.

[0083] In Figure 6a (naturally, with the start of the projectile motion at the left-hand end of the motion path in Figure 2 at 0 ms), impact with the applicator occurs after the overlap time and after the end of the second activation time, i.e., approximately 18-20 ms. This impact point gradually shifts to the left in the subsequent figures, and from Figure 6c onwards lies within the second activation time. The projectile velocities measured (optically in the experimental setup) range from 10 m / s in Figure 6a to 18 m / s in Figure 6e, i.e., in a ratio of 1:1.8.

[0084] In this case, it can be assumed, simply speaking (ignoring air pressure flow effects and projectile friction), that the projectile accelerates linearly over time before the second activation time and then continues to move at the velocity reached. In reality, the projectile velocity will likely increase somewhat more slowly than linearly over time, decreasing slightly in a nearly forceless manner during the overlap time due to friction. After the overlap time, the projectile 8 is braked in all cases by the application of the still-existing air pressure by the second valve. In the cases of Figures 6a and 6b, after the end of the second activation time, the projectile continues to travel a short distance before impact, almost forceless in the sense described above.

[0085] It is particularly noteworthy in FIG. 6a that the remainder of the second activation time after the overlap time is clearly longer than the (initial) remainder of the first activation time before the overlap time. This is surprising, since the same supply pressure hits both valves, and according to the actual values ​​from the above table of values, the impact nevertheless occurs at 10 m / s in FIG. 6a. One reason for this may be that the second valve 2 according to FIG. 2 is pneumatically connected significantly less efficiently to the interior of the projectile guide tube 7 in the region of its right-hand end than the first valve 1 at its left-hand end. This is related to the fact that, as can be seen in FIG. 2, at the right-hand end, the projectile 8 is prevented from flying out to the right by a narrowed cross section (a catcher). This has safety reasons in case the device without an applicator is accidentally activated. In this regard, the corresponding tube end apparently fills more slowly when the second valve 2 opens, which results in a relatively large delay between the valve switching process and the actual exertion of force due to the application of pneumatic pressure by the second valve in a dynamic sense.

[0086] Additionally, the figures show only in Figures 6d and 6e that a portion of the second activation time takes place after the impact. This does nothing to prevent the projectile from being pushed back by the impact itself, typically in terms of conservation of momentum, in the context of an impact between a low-mass projectile and a high-mass applicator. The remainder of the second activation time after the end of the first activation time in Figures 6d and 6e merely ensures additional return movement to the starting position at this point.

[0087] Naturally, the control time can be adapted to the extent that the overlap time ends approximately at the time of impact. In particular, this can be done by determining the time of impact by means of the possibility of a measuring coil 31 in the vicinity of the applicator 6, as already illustrated with reference to FIG. 2. The control time scheme will be somewhat complicated, since the first activation time must end earlier in each case (always earlier in FIGS. 6a to 6e). However, since the speed of the projectile's return movement can be increased, in each case the end of the second activation time is also provided accordingly for the slower of the individual instances, i.e., for higher projectile velocities, a higher repetition frequency range can be achieved when the projectile's velocity increases more rapidly.

[0088] Additionally, the electrical control time is exemplified here, and as a result, for the reasons already mentioned, there is actually an overlap time that is about 2 ms shorter.

[0089] Overall, one should envisage a control device (according to Figure 3) that can set control states according to the subexample of Figure 4, and can also set control states according to the subexample described above in Figure 6. In either case, the projectile velocity at impact can be affected by the constant pressure valve switching time.

[0090] 7 shows a schematic sequence of three actuations corresponding to FIG. 4f. In this example, as a result of the second activation times indicated by dashed lines, the projectile 8 is returned to its starting position, and then accelerated again in the direction of the applicator 6 at the first activation times that follow in chronological order. This diagram is intended only to illustrate possible periodicity of the control states, and of course applies equally to the other partial examples of FIGS. 4 and 6. In addition, it is envisaged that the successive processes may have an offset relative to one another, so that the impact process can be rapidly and freely changed from one repetitive actuation to the next.

[0091] Figure 8 shows a repeating sequence of pulses with two different projectile velocity ranges (at impact), which are designated in Figure 8 by the symbols "H" and "L". By varying the overlap and separation of the open times, here by way of example, the efficiency of the control device can be shown. Two pulses with projectile velocities approximately in range L reach a pulse with a projectile velocity approximately in range H, respectively.

[0092] Figure 8, in particular, reveals that crash conditions can vary substantially from one crash to the next, here by a factor of approximately three. In this example, the variations within ranges H and L are unintentional and are tolerance-related variations (these are actual measurements).

[0093] Figure 9 shows, by way of example, the control sequence of valves V1 and V2 in their time sequence to achieve the projectile velocity sequence that can be seen in Figure 8. Different overlaps and separations of the pulses relative to each other can be seen.

[0094] Figure 10 sets the pulse sequence according to Figure 9 more precisely in time so that the repeating sequence is now shown individually, and the relative changes in pulse separation and overlap between valves V1 and V2 can be seen more clearly.

[0095] The above description relates to the device shown in Figures 1 to 3. The description can also be transferred to other devices and dimensions based on simple assumptions about the projectile motion. In particular, the reversal point of the projectile motion is easily accessible, for example, by using the aforementioned measurement coils, possibly an analog measurement coil at the distal end of the motion path, or by using microphone impact detection. On this basis, meaningful assumptions can be made with reference to the above description.

[0096] Another possible procedure is to predefine the desired operating frequency and supply pressure for the two valves, and also predefine the duration of the opening of the two valves, e.g., 25% of the reciprocal of the predefined frequency. The control device can then be set to open and close the valves precisely in sync at the start. In this state, no stable motion occurs because pressure is applied to both sides of the projectile simultaneously, or because no pressure is applied from either side. Starting from this, it is possible to gradually change the offset between the opening times in both directions, i.e., gradually open (and close) the second valve slightly earlier or later than the first valve. Starting from a certain time offset, or in other words, a certain phase shift, will result in a stable oscillation state of the projectile, which can be established, for example, by the aforementioned microphone measurements of impacts at the two ends of the motion path. Furthermore, the intensity of the impact with the applicator can then be determined, taking into account the aforementioned phase shift as a control parameter for intensity. In this manner, a calibration curve can be determined.

[0097] It is also of course possible to keep the phase offset constant and vary the first and / or second valve opening periods in stages for a particular vibration condition determined in this manner.

[0098] In individual cases, it may happen that sufficient pressure for the desired frequency was not predefined, i.e., a vibration situation with a collision at the end of the movement path does not occur even in the case of "anti-phase" control of the two valves. It is necessary to increase the pressure slightly or reduce the frequency accordingly.

[0099] Likewise, it is of course possible to empirically approach the appropriate operating conditions in other ways. Finally, it is of course possible to at least approximately simulate the kinematic behavior of the projectile computationally, and then empirical tests can be carried out based on the results of this simulation.

Claims

1. A device for treating the body of a human or animal using mechanical pressure waves, A projectile (8) guided along a path within the device, An applicator (6) located at one end of the aforementioned motion path, Includes a pneumatic means for applying air pressure to the projectile (8) for motion along the aforementioned motion path, The projectile (8) is configured to collide with the applicator (6) in order to generate a mechanical pressure wave. The pneumatic means includes a double valve means (1, 2) for applying pneumatic pressure to the projectile (8) in the direction toward the applicator (6) during a first activation time and for applying pneumatic pressure to the projectile (8) in the opposite direction during a second activation time, and a control means (54) for controlling the double valve means (1, 2). The apparatus is configured to maintain a separation time between the first activation time and the second activation time, or vice versa, and to control the impact velocity of the projectile (8) upon impact with the applicator (6) by the separation time.

2. The aforementioned double valve means (1, 2) A first valve for applying air pressure to the projectile (8) in the direction toward the applicator (6), The apparatus according to claim 1, further comprising a second valve for applying air pressure to the projectile (8) in the reverse direction.

3. The apparatus according to claim 2, wherein the first valve and the second valve can be controlled independently of each other by the control means (54).

4. The dual valve means (1, 2) has a combination valve that, in response to control by the control means (54), takes either a first switching state in which air pressure is applied to the projectile (8) in the direction toward the applicator (6) or a second switching state in which air pressure is applied to the projectile (8) in the opposite direction. The apparatus according to claim 1, wherein in each of the first and second switching states, the pneumatic connection used in the other switching state for applying air pressure to the projectile (8) is ventilated by the combination valve.

5. At least one of the first valve (1) and the second valve (2) is a two-way valve, The apparatus according to claim 2, wherein the two-way valve applies air pressure to the air pressure volume between the two-way valve and the projectile (8) at the first switching position during each activation time for applying air pressure to the projectile (8), and ventilates the air pressure volume at the second switching position.

6. The apparatus according to any one of claims 1 to 5, wherein the first activation time is of a variable length compared to at least two control states having different separation times.

7. The apparatus according to any one of claims 1 to 5, wherein, in certain control states, one of the two activation times is configured to end only after the other of the two activation times has started.

8. The apparatus according to claim 7, wherein the first and second activation times are configured to overlap by an overlap time by ending the first activation time during the other activation time.

9. The apparatus according to claim 7, wherein, in the case of the aforementioned control state, the impact velocity of the projectile (8) upon impact with the applicator (6) is controlled by the portion of the first activation time other than the overlap time associated therewith.

10. The apparatus according to claim 9, wherein, when comparing at least two control states in which the overlap period between the first activation time and the second activation time differs, the earlier of the two activation times is of a constant length.

11. The apparatus according to claim 9, wherein the slower of the two activation times is of variable length when compared between at least two control states with different overlapping periods.

12. The aforementioned pneumatic means includes a pneumatic compressor, The apparatus according to any one of claims 1 to 5, wherein the apparatus is configured such that during the activation time the compressor operates at the same rotational speed in each control state where the impact velocity of the projectile (8) is different.

13. The apparatus according to claim 12, wherein the apparatus is configured to enable the compressor to always operate at the same rotational speed during the activation time.

14. The apparatus according to any one of claims 1 to 5, wherein the projectile (8) is capable of moving with an impact pulse between 2 gm / s and 300 gm / s when impacting the applicator (6).

15. The apparatus according to any one of claims 1 to 5, wherein, in a repetitive operation state in which the forward and return motions of the projectile (8) for impacting the applicator (6) are directly and continuously performed, the impact velocity and / or duration of the combined forward and return motions is configured to vary from one of the combined forward and return motions to the next.

16. The apparatus according to any one of claims 1 to 5, further comprising a measuring means for detecting the passage of the projectile (8) at one point along the motion path, the measuring means being connected to the control means (54).

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