Pressure wave device with dual valve means

Abstract

The present invention relates to an apparatus for treatment using pressure waves. The apparatus 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 move it along the path of motion. The projectile (8) is configured to strike the applicator (6) to generate pressure waves. 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) for the dual valve means (1, 2). The apparatus is configured to allow for overlapping of the activation times.

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 (typically cyclically repeated) 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, sets in motion the air located in front of it, thereby essentially pumping up the storage volume.

[0006] In addition to controlling the opening time of the switching valve with respect to acceleration, which is not described in detail, U.S. Pat. No. 5,629,499, which was revoked in opposition proceedings for lack of reproducibility, the patent also describes pressure limiting in the opposing pressure chamber. Alternatively, 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 aims to embody a device of the above type with pneumatic means for projectile movement, the device being 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 invention has, as part of its pneumatic means, a double valve means, e.g., a combination of a first valve and a second valve, which directs the projectile in both directions, i.e., toward the applicator and away from it 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., during the activation phase of the first valve, for example, is referred to below as the first activation time, and the opposite time phase, during which the projectile is urged in the opposite direction, is referred to as the second activation time. According to the 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 already while the first activation time is still ongoing, or vice versa. Thus, there is an overlap between the two valve opening times.

[0011] As a result, different advantages can be achieved in individual cases depending on the requirements and center of gravity. Essentially, the present invention provides an additional degree of freedom in the overlap time, which can be used, for example, to control the impact velocity of the projectile striking 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, an opposing force acts on the projectile in addition to the air pressure accelerating it forward. In the simplest case, if approximately the same air pressure is used, this opposing force will be approximately equal in magnitude, substantially canceling out the acceleration. Depending on the length of the first valve opening period prior to this time, the projectile will accelerate to a higher or lower velocity, and then will maintain that velocity for the duration of the overlap period, for example, until impact.

[0012] 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.

[0013] 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).

[0014] 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.

[0015] 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.

[0016] 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.

[0017] A further (alternative or additional) embodiment may be to operate at a relatively high air pressure in order to achieve a rapid return and therefore a high operating frequency, but without necessarily using a high impact velocity corresponding to this high pressure (when such acceleration pressures are 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.

[0018] 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.

[0019] 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.

[0020] 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.

[0021] On the other hand, the combination valve also has a further third switching state in which the two pneumatic connections are applied (simultaneously) with the pneumatic supply pressure. In this third switching state, there is an overlap between the first activation time and the second activation time. Therefore, if the start of the second activation time during the first activation time (or vice versa) is as described above, this means that in the variant with the combination valve, this combination valve switches or toggles. The same applies to the end of the first activation time while the second activation time is still running (or vice versa), i.e., the end of the overlap time.

[0022] 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.

[0023] 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.

[0024] 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.

[0025] 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. This therefore results in a final phase of this forward movement, during which pressure exists on both sides of the projectile. This leads to the possibility already described at the beginning. 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.

[0026] 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 synchronism towards the end of the return movement, i.e., before the next acceleration process or event.

[0027] In particular, the overlap time may be partially before and partially after the impact of the projectile on the applicator, or partially before and partially after it reaches its farthest point from the applicator, as will be described in more detail in connection with the illustrative embodiments.

[0028] 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.

[0029] 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.

[0030] Preferably, if an overlap time or a part of the overlap time also exists at least during the forward movement (i.e. before the impact), then a part of the first activation time before or after this overlap time (depending on the case under consideration) is preferably used to control the impact velocity. In this case, simply speaking, for example, a limited or even very few separate such parts of the first activation time are provided, and in the simplest case only two can be set by the control means. This includes the case where there is zero overlap time in one of the two control states (or more broadly, in part of the control states).

[0031] For example, as shown in the illustrated embodiment, when a small number of separate, different overlap times are provided, these overlap times are given by the beginning of the second activation time being offset from the beginning of the first activation time (e.g., with a constant end for each of the two activation times). In a control state with the earliest beginning of the second activation time (e.g., a constant supply pressure), the actual acceleration of the projectile is shorter than in other control states with a later beginning of the second activation time. Therefore, the projectile accelerates to a relatively slower velocity, and at this point, it takes more time to impact. With a later beginning of the second activation time (or an earlier end of the second activation time), the projectile velocity increases, and at the same time, the point of impact shifts forward relative to the beginning of the projectile's motion. Preferably, in the first case, i.e., in the case of an overlap time at the end of the first activation time, the collision of the projectile with the applicator also remains within the overlap time in the control state with the highest projectile velocity, i.e., the latest beginning of the second activation time. See, for example, Figures 4a-4e and their accompanying descriptions.

[0032] 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).

[0033] 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.

[0034] 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.

[0035] In other cases, the description does not necessarily relate to individual motion steps within such a motion sequence. Operating conditions, as described in more detail, may change during the sequence, so that the described overlap times may not exist at all in some of the motion sequences within the sequence, for example.

[0036] According to a preferred configuration, the device, and in particular the control means, may even be configured such that in certain control states there is no such overlap time, but rather a "separation time" (different from zero) is maintained between the end of the first (or second) activation time and the beginning of the second (or first) activation time.

[0037] 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, only a first portion of the available time between the projectile's initiation of motion and its impact on the applicator, rather than the entire time available, is used for acceleration in the presence of an acceleration pressure. For example, the impact velocity of the projectile can be reduced in this manner without reducing the acceleration 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.

[0038] Furthermore, the separation time may occur completely or partially after the impact, and a premature return movement or a high velocity at the end of the return movement may 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.

[0039] 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.

[0040] Of course, a further separation time may follow the second activation time following the aforementioned separation time (or there may be no such separation time after the second activation time), for example, the second activation time need not last all the way until the projectile reaches the distal location.

[0041] Preferably, the first activation time is variable in at least two control states with different separation times, i.e., with a fixed portion (including zero) of the separation time after the collision. Naturally, the second activation time can also be variable, but can also be completely constant in duration and / or start and end relative to the collision, for example in the case of the just-mentioned fixed portion of the separation time after the collision, and particularly preferably.

[0042] 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.

[0043] 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.

[0044] 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.

[0045] 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.

[0046] 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, allowing the activation time to be appropriately matched to the moment of impact (particularly as to its start and end).

[0047] 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).

[0048] 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]

[0049] [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 4e) 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 6f) 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 series of schematic time charts (FIGS. 8a-8c) are shown for further explanation of the mode of operation. [Figure 9] 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 10] 10 shows a control sequence for controlling valves V1 and V2 according to a sequence of two different projectile velocity levels shown in FIG. [Figure 11] The first 300 ms from the control sequence in Figure 10 are shown in higher resolution temporal detail. [Figure 12] Specifically, with reference to the display of FIG. 13, there is shown the relationship, as determined by actual measurements, between the portion of first valve open time before overlap time on the horizontal axis and projectile impact velocity on the vertical axis. [Figure 13] Associated with each individual measurement point in FIG. 12 are a series of time lapse plots (FIGS. 13a-13d) illustrating the actual valve opening times and the respective overlap times therebetween. DETAILED DESCRIPTION OF THE INVENTION

[0050] 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 to the left in Figure 1, or as shown in Figure 2. It can also be made up of multiple parts.

[0051] 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.

[0052] 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.

[0053] FIG. 2 shows a longitudinal section of the entire device along the imaginary central longitudinal axis of the aforementioned cylindrical shape, which also coincides with the central longitudinal axis of the projectile guide tube 7. To illustrate the dimensions, in this embodiment, the length of the projectile guide tube 7 is 145.5 mm; the remaining illustrations in FIG. 2 are to scale. 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 aforementioned screw rings 4 and 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, a device design 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), is also possible and preferred.

[0054] 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.

[0055] 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.

[0056] 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).

[0057] 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.

[0058] 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.

[0059] 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.

[0060] 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.

[0061] 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.

[0062] 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.

[0063] 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.

[0064] 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 4 bar may be assumed as an example. This leads to the following list of values: -List of values- Projectile speed [m / s]: 10; 12; 14; 16; 18 Valve 1 open time [ms]: 0; 0; 0; 0; 0 Valve 1 closing time [ms]: 13.0; 13.0; 13.0; 13.0; 13.0 Valve 2 opening time [ms]: 2.6; 3.0; 3.7; 5.0; 7.1 Valve 2 closing time [ms]: 18 ; 18 ; 18 ; 18 ; 18 Valve 2 on duration [ms]: 15.4; 15.0; 14.3; 13.0; 10.9 Overlap time [ms]: 10.4; 10.0; 9.3; 8.0; 5.9

[0065] Figure 4 shows a series of five individual schematic time charts (Figures 4a to 4e) corresponding to the above list. 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 similarly represented by a curve marked "T2". Thus, the increasing curve portions correspond to the first and second activation times, respectively.

[0066] 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 a stepwise manner with respect to its onset, from 2.6 ms in FIG. 4a to 7.1 ms in FIG. 4e, while the second activation time ends at 18 ms in all five examples. Thus, there is an overlap time in all control states, namely, from approximately 3 ms to 13 ms in FIG. 4a to approximately 7 ms to 13 ms in FIG. 4e. This overlap time decreases in a stepwise manner, i.e., corresponding to the 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.

[0067] In the case illustrated in Figure 4, 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 in the order of Figures 4a through 4e. This corresponds to an impulse of 30 gm / s to 54 gm / s for a projectile mass of 3 g. The opening time of valve 1 is a constant 13.0 ms. The closing time of the second valve also remains a constant 18 ms.

[0068] More precisely, Figures 4a-4e 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 for opening and 2 ms for closing. That is, the overlap time is actually approximately 2 ms shorter than shown.

[0069] In the case of so-called pilot valves with pneumatic assistance when opening, the situation is qualitatively equivalent.

[0070] In Figure 4a (naturally, with the start of the projectile motion at the left-hand end of the motion path in Figure 2 at 0 ms), the 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 4c onwards lies within the second activation time. The projectile velocities measured (optically in the experimental setup) range from 10 m / s in Figure 4a to 18 m / s in Figure 4e, i.e., in a ratio of 1:1.8.

[0071] 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 4a and 4b, 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.

[0072] It is particularly noteworthy in FIG. 4a 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. 4a. 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.

[0073] Additionally, the figures show only in Figures 4d and 4e 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 4d and 4e merely ensures additional return movement to the starting position at this point.

[0074] Naturally, the control times can be adapted to the extent that the overlap times respectively end approximately at the impact time. In particular, this can be done by determining the impact time in time 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. If the impact time is intended to be relatively precisely positioned at the end of the overlap time (or at another fixed point), the control time scheme will be somewhat more complicated, since the first activation time respectively must end earlier (always earlier in FIGS. 4a to 4e). However, the speed of the projectile movement, especially the return movement, can be increased. In this case, it would be interesting to respectively end the second activation time at a higher projectile speed and also to increase the projectile speed earlier in order to achieve an even higher repetition frequency range.

[0075] Of course, in the case of another embodiment with a "combination valve," very similar relationships to those shown in Figures 4a-4e can be created, but in this case the overlap times represent different switching states of the valves. 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 denotes, 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 denotes, for example, a connection to the right-hand side of the projectile guide tube 7 via channel 25 (analogous to the second valve 2).

[0076] In FIG. 5, the upper line connection 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.

[0077] 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 top 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 bottom position shows simultaneous pressurization of both line V1 and line V2.

[0078] 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.

[0079] 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.

[0080] 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.

[0081] Figure 6 shows a schematic time chart similar to Figure 4, in each of Figures 6a-6c, but with a separation between the control of Valve 1 according to Figures 1 and 2, shown in solid lines below, and the control of Valve 2, shown in dashed lines above. In Figure 6a, the activation pulse of Valve 1 is relatively short, which accelerates the projectile and, after the first activation period, "flies" through a significant portion of its path of motion without further air pressure application. In contrast to the overlap period shown in Figure 4, both sides of the tube interior are ventilated (not pressurized) during this phase of motion.

[0082] After a certain time, a collision with the applicator occurs, as symbolically shown in Figure 6a, after which a relatively short (in addition to the return movement of the projectile due to this collision alone) return air pressure pulse occurs as a result of a second activation time according to the dashed line in Figure 6a, thus returning the projectile to its starting position again and making it available for a new cycle.

[0083] In each of Figures 6b and 6c, the above description essentially applies equally clearly, except that the first activation time is progressively longer and the separation time between the first and second activation times is correspondingly shorter. As a result, the impact point is shifted slightly to the left, as symbolically shown. Correspondingly, the projectile impacts the applicator at increasingly higher speeds.

[0084] In all three charts 6a-6c, the activation time of the second valve is after the collision. In the first two control states, 6a and 6b, the majority of the separation time is before the collision, followed by the third case, 6c.

[0085] In Figures 6d-6f, unlike Figures 6a-6c, the length of the first activation time is constant (corresponding to Figure 6b). On the other hand, unlike the first three examples, part of the second activation time occurs before the collision, specifically, most of it in Figure 6d, roughly half of it in Figure 6e, and only a small portion in Figure 6f. The example of Figure 6b, in which the second activation time occurs entirely after the collision, can be considered to be somewhat continuous, but this is not particularly important here.

[0086] These examples illustrate further possibilities for controlling the velocity of the projectile upon impact. In Fig. 6d, the projectile is accelerated by air pressure through a first activation period, i.e., similar to Fig. 6b, but unlike Fig. 6b, it flies forcelessly for a relatively short period, after which it is slowed by opposing air pressure as a result of the start of a second activation period (upper dashed line). In Fig. 6d, the delay period corresponds approximately to the acceleration period, and the same pressure level can be assumed, so the projectile strikes the applicator with minimal velocity and then returns for the remainder of the second activation period.

[0087] In Figures 6e and 6f, 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.

[0088] In this regard, it is necessary to 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 both cases, the projectile velocity at impact can be affected by the constant pressure valve switching time.

[0089] Figure 7 shows a schematic sequence of three actuations corresponding to Figure 6e. In this example, the second activation times, indicated by dashed lines, result in the projectile being returned to its starting position, and then, at the first activation time that follows in chronological order, it is accelerated back towards the applicator. This diagram is intended only to illustrate possible periodicity of the control states, and of course applies equally to the other examples of Figures 4 and 6. In addition, it is envisioned that successive processes may have offsets with respect to one another, so that the impact process can be rapidly and freely changed from one repetitive actuation to the next.

[0090] FIG. 8 shows a series of three separate schematic time charts, 8a-8c, in which the opening and closing process of the first valve 1 is shown by the curve labeled T1, and the opening and closing process of the second valve 2 is shown by the curve labeled T2. The increased curve portions correspond to the first and second activation times, respectively. Compared to the time chart of FIG. 4, the second valve opens chronologically earlier, corresponding to curve T2, than the first valve, corresponding to curve T1. By varying the overlap between the two activation times, the recoil at the distal end of the movement path occurs earlier or later, as indicated on the horizontal axis in the three diagrams. In this example, both activation times are identical in length (comparing the three individual examples with each other). Meanwhile, the second activation time gradually shifts forward relative to the first activation time from FIG. 8a to FIG. 8b and then to FIG. 8c, resulting in a decrease in the overlap time. Because the portion of the second valve opening time available for reverse acceleration (before the overlap time) is longer in Figure 8c than in Figure 8b, and even longer than in Figure 8a, the projectile velocity present upon distal recoil is correspondingly greater. As a result, the projectile moves back toward the applicator at a correspondingly higher velocity after distal recoil. Also, as shown by a comparison of Figures 8a-8c, the portion of the first valve opening time available for corresponding additional acceleration (after the overlap time) is also longer, resulting in an increase in impact velocity upon impact with the applicator from Figure 8a to Figure 8b and finally Figure 8c, for two reasons:

[0091] FIG. 9 shows a repeating sequence of pulses having two different projectile velocity ranges (at impact), designated in FIG. 9 by the symbols "H" and "L." By varying the overlap time and separation time, the efficiency of the control system can be shown, here by way of example. Two pulses having projectile impact velocities approximately in range L arrive at a pulse having projectile impact velocities approximately in range H. FIG. 9 particularly reveals that impact conditions can vary substantially from one impact to the next, here by approximately three times the impact velocity. In this example, the variations within ranges H and L are unintentional and are tolerance-related variations (these are actual measurements).

[0092] Figure 10 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 9. Different overlaps and separations of the pulses relative to each other can be seen.

[0093] Figure 11 sets the initial pulse sequence of Figure 10 more precisely in time so that the repeating sequence is now shown individually. The relative changes in valve opening times between valves V1 and V2 as well as their separation and overlap can be more clearly seen.

[0094] Figures 12 and 13a-13d relate to additional actual laboratory measurements in addition to those listed above (for Figures 4a-4e). The measurements were generated with the apparatus described in Figures 1-3 at a repetition rate of 10 Hz and a constant supply pressure of 4 bar, with a constant valve open time of 14 ms for both Valve 1 and Valve 2. At the four measurement points shown in Figure 12, from left to right corresponding to the following figures, the overlap times, indicated by the symbol δ in Figures 13a-13d, were 6 ms, 5 ms, 4 ms, and 3 ms. As a result, the "net pulse duration" of the accelerating pneumatic pressure pulse (before the overlap time δ) for the first valve V1, shown on the horizontal axis in Figure 12, was correspondingly 8 ms to 11 ms.

[0095] Again, this is not a surprising result; the very monotonically increasing relationship can be easily seen in Figure 12, based on the dashed interpolated line. The more time available for acceleration (without changing pressure), the higher the impact velocity. Impact occurred approximately between 16 ms and 17 ms, i.e., just after the end of the first valve opening and overlap periods and during the second valve opening period. Relatedly, in all illustrated operating conditions, there was a small damping action of the air pressure pulse by the second valve, and in all illustrated conditions, some half or more of the second valve opening period was used for the safe and rapid return of the projectile. Varying the overlap period altered the portion of the first valve opening period available for acceleration and, hence, impact velocity.

[0096] The above description based on Figures 4 and 6 to 13 relates to the device shown in Figures 1 to 3. The description can also be transferred to other devices and dimensions based on simple estimations regarding 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 detecting the impact by microphone. On this basis, meaningful estimations can be made with reference to the above description.

[0097] Another possible procedure is to predefine the desired operating frequency and supply pressure for the two valves, and also predefine the duration of the two valves, e.g., 40% 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 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.

[0098] 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.

[0099] 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.

[0100] 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 such that the first activation time and the second activation time overlap by an overlap time.

2. The aforementioned double valve means (1, 2) A first valve (1) 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 (2) for applying air pressure to the projectile (8) in the reverse direction.

3. The apparatus according to claim 2, wherein the first valve (1) and the second valve (2) are controllable 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, or a third switching state is taken in which, in response to control by the control means (54), air pressure is applied by the combination valve to both pneumatic connections used for applying air pressure to the projectile (8).

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 control means (54) is configured to control the collision velocity of the collision between the projectile (8) and the applicator (6) by changing the overlap time.

7. The apparatus according to any one of claims 1 to 5, wherein if the overlap time is at the end of the first activation time, the second activation time begins during the forward motion of the projectile (8), and / or, if the overlap time is at the end of the second activation time, the first activation time following the second activation time begins during the return motion of the projectile (8).

8. The apparatus according to any one of claims 1 to 5, configured to terminate the first activation time during the second activation time or vice versa.

9. The apparatus according to any one of claims 1 to 5, wherein the impact velocity of the projectile (8) upon impact with the applicator (6) is controlled by a 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 of 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 apparatus according to claim 9, wherein the control means (54) is configured to change the separation time between the first activation time and the second activation time in different control states.

13. The aforementioned pneumatic means includes a pneumatic compressor (53), The apparatus according to any one of claims 1 to 5, wherein the apparatus is configured such that the compressor (53) operates at the same rotational speed in each control state where the impact velocity of the projectile (8) is different during the activation time.

14. The apparatus according to claim 13, wherein the apparatus is configured to enable the compressor (53) to always operate at the same rotational speed during the activation time.

15. 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).

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

17. The apparatus according to any one of claims 1 to 5, further comprising a measuring means (31) for detecting the passage of the projectile (8) at one point along the motion path, the measuring means (31) being connected to the control means (54).

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