An array-type liquid-electric shock wave controllable focusing device and control method

Abstract

An array-type electrohydraulic shock wave controllable focusing device, comprising a housing, an energy storage electrical appliance, electrodes, and a energy transmission liquid. The energy transmission liquid is arranged in the housing, and the electrodes are immersed in the energy transmission liquid. The electrodes include a negative electrode and a positive electrode matrix with a number of equally spaced linear arrangements. The positive electrode matrix is electrically connected to an array switch, the array switch is electrically connected to the energy storage electrical appliance, and the array switch is also electrically connected to a microprocessor, and the microprocessor is used to store the time delay of the positive electrode matrix. The array-type electrohydraulic shock wave controllable focusing device disclosed by the present invention controls the excitation signals of each electrode element based on the near-field beamforming principle. By planning the linear distribution of the positive electrodes, T-shaped negative electrodes, and the high-voltage discharge positions of each electrode element, the near-field beamforming filter approximate time delay simplification system is used. Based on the output of the microprocessor, the corresponding time delay of each electrode element is obtained, and the array switch is controlled to achieve the controllable focusing of each electrode element.

Description

Technical Field

[0001] The present invention relates to a liquid-electric shock wave generating device, and particularly to a control method and device for controllable focusing of an array-type liquid-electric shock wave. Background Art

[0002] The extracorporeal shock wave technology of the liquid-electric type has been widely used in the medical field for treating urinary calculi in the human body. Its basic technical principle is to generate shock waves through discharge and use reflection or an acoustic lens to achieve energy focusing. Through water medium for impedance matching, the focused shock waves are introduced into the human body, and the stones are crushed by the concentrated physical effect generated by energy focusing.

[0003] The basic technical principle of existing liquid-electric focused shock wave medical devices is to use the electrode tip of an electrode rod for high-voltage discharge to generate radial liquid-electric shock waves, and through a reflection structure, such as an ellipsoidal reflecting surface, to focus the shock waves, so that the liquid-electric shock waves achieve energy focusing at the focus of the reflection structure. Although this technical principle is simple to implement and has a high energy conversion efficiency, using a single electrode as the energy source to generate focused shock waves, although focused by the reflecting surface, still requires a relatively high discharge voltage, resulting in the electrode tip being easily damaged after multiple high-voltage discharges and becoming a consumable, increasing the equipment usage cost. At the same time, due to the fixed focus of the reflection structure, before shock wave treatment, it is necessary to use scanning equipment such as X-rays for stone positioning and then control the entire reflection structure through a moving mechanism to align the quality, resulting in high complexity of the medical device, time-consuming positioning process, reduced treatment efficiency, and increased equipment operation workload.

[0004] To overcome the defects existing in the prior art, Chinese Patent CN200310112407.5 proposes a multi-purpose directional shock wave generating device. This device generates directionally emitted shock waves and has multiple output modes. In addition to parallel output, when focusing is required, it can use a curved surface for stable focusing without causing drift of the shock wave focusing point. Since the discharge end is changed to a convex object such as a discharge ball, the service life is greatly extended. However, this technical solution requires the overall replacement of different-shaped discharge ends, and for the same discharge end, the shock wave focusing point still cannot be flexibly adjusted.

[0005] Aiming at the requirements of low complexity and low cost of liquid-electric focused shock wave medical devices in specific medical application scenarios, the purpose of the present invention is to utilize the flexible adjustment characteristics achievable by array focusing, and through multiple electrodes forming an array for controlled focusing, to provide a control method and device for controllable focusing of an array-type liquid-electric shock wave. Summary of the Invention

[0006] Aiming at the deficiencies in the background art, the purpose of the present invention is to provide a control method and device for controllable focusing of an array-type liquid-electric shock wave.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] An array-type liquid-electric shock wave controllable focusing device, comprising a housing, an energy storage electrical appliance, electrodes and a energy transmission liquid, characterized in that the energy transmission liquid is arranged in the housing, and the electrodes are immersed in the energy transmission liquid; the electrodes include a negative electrode having a T-shaped structure and a positive electrode matrix composed of m equally spaced linearly arranged positive electrodes, and each of the positive electrodes forms an electrode element with the negative electrode; the positive electrode matrix is electrically connected to an array switch, the array switch is electrically connected to the energy storage electrical appliance, and the array switch is also electrically connected to a microprocessor, and the microprocessor is used to store the time delay of the positive electrode matrix.

[0009] The spatial coordinates of the m-th electrode element are (x m , y m , z m ). The focusing position of the controllable shock wave is within the near field range of the array. Taking the center of the array as the coordinate origin, the distance between the focusing position and the coordinate origin is r, the azimuth angle is θ, and the elevation angle is Then the distance between the m-th positive electrode and the focusing position can be expressed as:

[0010]

[0011] The received signal of the shock wave signal discharged by the m-th electrode at the focusing position can be expressed as:

[0012]

[0013]

[0014]

[0015] m (t) is used for near-field focusing processing. Then the shock wave signals of each electrode received at the focusing position are:

[0015]

[0016] The near-field beamforming formula can obtain the near-field beamforming filter h m (t);

[0017] The electrode time delay corresponding to the m-th electrode can be expressed as:

[0018]

[0019] After the shock wave signals of each electrode element received at the focusing position are controlled by time delay, controllable focusing of the shock wave is achieved, which can be expressed as:

[0020]

[0021] Among them, the function δ is a unit impulse function, which is used to control the time delay and output to control the mth electrode element.

[0022] Furthermore, the energy storage electrical appliance is a high-voltage discharge capacitor.

[0023] Furthermore, the housing is provided with a water inlet and a water outlet.

[0024] Furthermore, the energy transfer liquid is clean water.

[0025] A control method for an array-type liquid-electric shock wave controllable focusing device, which is applicable to the aforementioned controllable focusing device, includes the following steps:

[0026] Step 1: Time delay generation, calculate and generate electrode time delays corresponding to the respective focusing positions of the shock wave, and store the electrode time delays in the microprocessor;

[0027] Step 2: Focusing position input, determine the shock wave focusing position according to the treatment needs and input it into the microprocessor;

[0028] Step 3: Control the selective energization time of each positive electrode in the electrode array, retrieve the corresponding electrode time delay in the microprocessor according to the input shock wave focusing position, and the microprocessor controls the energization time of each electrode according to the electrode time delay;

[0029] Step 4: Each electrode generates a shock wave, and the shock waves generated by each electrode are aligned and focused in time through the time delay, so as to realize the shock wave focusing at the corresponding focusing position.

[0030] The beneficial effects of the present invention are:

[0031] A control method and device for array-type liquid-electric shock wave controllable focusing proposed by the present invention. The disclosed array-type liquid-electric shock wave controllable focusing device controls the excitation signals of each discharge electrode in each array based on the near-field beamforming principle. By designing a linear positive electrode array, a T-shaped negative electrode and ensuring the linear distribution of the high-voltage discharge positions of each electrode element, and further realizing it through the approximation of the near-field beamforming filter and time delay to simplify the system, so that the corresponding time delays of each electrode element can be output based on the microprocessor, and the array switch is controlled to realize the controllable focusing of each electrode element.

[0032] Therefore, through an array-type electrohydraulic shock wave controllable focusing device proposed by the present invention, while significantly reducing the discharge voltage of each electrode of the electrode array, the shock wave focusing intensity and treatment effect can be ensured, and the mechanical moving device of the traditional focusing reflection structure can be omitted to achieve controllable digital focusing on the position of the stone. Therefore, in the actual medical operation of electrohydraulic focused shock wave medical equipment, rapid and accurate alignment can be achieved, which is beneficial to reducing equipment costs and improving efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0034] Figure 1 It is a schematic diagram of the electrode array elements of an array-type electrohydraulic shock wave controllable focusing device of the present invention;

[0035] Figure 2 It is a schematic diagram of an array-type electrohydraulic shock wave controllable focusing device of the present invention;

[0036] In the figure: housing 10, energy storage electrical appliance 20, negative electrode 30, positive electrode matrix 40, energy transmission liquid 50, array switch 60, microprocessor 70, water inlet 801, water outlet 802, focusing position 90. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0037] The following will be combined with Figure 1 - Figure 2 to describe the present invention in detail.

[0038] An array-type electrohydraulic shock wave controllable focusing device includes a housing 10, an energy storage electrical appliance 20, electrodes, and an energy transmission liquid 50. The energy transmission liquid 20 is arranged in the housing 10, and the electrodes are immersed in the energy transmission liquid 50; the electrodes include a negative electrode 30 and a plurality of positive electrode matrices 40 arranged linearly with equal spacing; each positive electrode 401 in the positive electrode matrix 40 is electrically connected to an array switch 60, the array switch 60 is electrically connected to the energy storage electrical appliance 20, and the array switch 60 is also electrically connected to a microprocessor 70. The microprocessor 70 is used to store the time delay of the positive electrode matrix 40.

[0039] Preferably, the negative electrode has a T-shaped structure.

[0040] Preferably, the energy storage electrical appliance is a high-voltage discharge capacitor. Preferably, the housing is provided with a water inlet and a water outlet.

[0041] Preferably, the energy transmission liquid is clean water.

[0042] The present invention also provides a control method for an array-type liquid-electric shock wave controllable focusing device, comprising the following steps:

[0043] Step 1: Time delay generation, calculating and generating electrode time delays corresponding to each focusing position of the shock wave, and storing the electrode time delays in the microprocessor;

[0044] Step 2: Focusing position input, determining the shock wave focusing position according to the treatment requirement and inputting it into the microprocessor;

[0045] Step 3: Controlling the selective energization time of each positive electrode in the electrode array, calling out the corresponding electrode time delay in the microprocessor according to the input shock wave focusing position, and the microprocessor controls the energization time of each electrode according to the electrode time delay;

[0046] Step 4: Each electrode generates a shock wave, and the shock waves generated by each electrode are aligned and focused in time through the time delay, realizing the focusing of the shock wave at the corresponding focusing position.

[0047] Considering the application characteristics of liquid-electric focused shock wave treatment, the focused shock wave is in the near-field range, and the shock wave front generated by the discharge of the electrode array is a spherical wave rather than a plane wave. Therefore, the control signal needs to be generated according to the near-field array beam control method.

[0048] Assume that the electrode is an M-element electrode array, that is, the electrode is composed of a T-shaped negative electrode and m positive electrodes, and each positive electrode and the T-shaped negative electrode form an electrode array element. The focusing position 90 of the controllable shock wave is within the near-field range of the array. Taking the center of the array as the coordinate origin, the distance between the focusing position S and the coordinate origin is r, the azimuth angle is θ, and the elevation angle is Then as Figure 1 shown.

[0049] Generally, let the spatial coordinates of the mth element of the M-element array be (x m , y m , z m ), its distance to the origin is r m , and the distance between the focusing position 90 and the origin is r. Then the distance d between the mth positive electrode and the focusing position S is m It can be expressed as:

[0050]

[0051] Considering the two-dimensional simplified situation, set the controllable shock wave focusing position S on the z-axis, that is, θ = 90°, d m Can be written as:

[0052] d m =(x m 2 +r 2 )1 / 2

[0053] Considering the two-dimensional simplified case, in this embodiment, M = 8, that is, there are 8 positive electrodes, a total of 8 electrode elements. The 8 positive electrodes are arranged equidistantly on the x-axis, the center of the array is the coordinate origin, and the element spacing is d. Then, there are:

[0054]

[0055] Therefore, it can be known that the received signal of the shock wave signal discharged by the m-th positive electrode at the focusing position S can be expressed as:

[0056]

[0057] Where t is the time coordinate, A is the discharge voltage amplitude constant of the energy storage electrical appliance, w is the angular frequency of the shock wave signal, k = 2π / λ, and λ is the wavelength of the shock wave signal.

[0058] According to the near-field beamforming principle, a shaping filter h of order L is used m (t) for near-field focusing processing. Then, the shock wave signals of each element received at the focusing position 90 are:

[0059]

[0060] The near-field beamforming filter h can be obtained by using the well-known near-field beamforming formula in the art m (t):

[0061]

[0062] Where r0 is the coordinate on the Z-axis when the focusing position 90 is set on the Z-axis.

[0063] Considering that in this embodiment, the electrode discharge is a transient process. For the sake of simplifying the system consideration, each electrode element is selectively turned on by time delay to perform controllable shock wave focusing, that is, equivalently, spatial focusing is achieved by controlling the time delay discharge of the m-th electrode element. The time delay τ of the time delay discharge of the m-th electrode element m Can be expressed as:

[0064]

[0065] Then, the shock wave signals of each electrode element received at the focusing position 90 on the Z-axis will achieve controllable shock wave focusing at the r0 position after time delay control, which can be expressed as:

[0066]

[0067] Wherein: the function δ is a unit impulse function, and in this embodiment, the time delay is controlled by the microprocessor 70 and output to the m-th electrode element corresponding to the array switch control electrode.

[0068] It should be noted that for the convenience of description, the above derivation process is simplified in two dimensions, and this processing method is also applicable in a three-dimensional scenario, that is, the focusing position can be set in a three-dimensional plane.

[0069] In summary, an array-type electrohydraulic shock wave controllable focusing device proposed by the present invention. The disclosed array-type electrohydraulic shock wave controllable focusing device controls the excitation signals of each discharge electrode in each array based on the near-field beamforming principle. By designing a linear positive electrode array, a T-shaped negative electrode, and ensuring the linear distribution of the high-voltage discharge positions of each electrode element, and further realizing it through the approximation time delay simplification system of the near-field beamforming filter, so that the corresponding time delay of each element can be output based on the microprocessor, and the switch array can be controlled to realize the controllable focusing of each electrode element.

[0070] Therefore, through the array-type electrohydraulic shock wave controllable focusing device proposed by the present invention, while significantly reducing the discharge voltage of each electrode of the electrode array, the shock wave focusing intensity and treatment effect can be ensured, and the mechanical moving device of the traditional focusing reflection structure can be omitted to realize the controllable digital focusing of the alignment of the stone position. Therefore, in the actual medical operation of the electrohydraulic focusing shock wave medical device, rapid and accurate alignment can be achieved, which is beneficial to reducing the equipment cost and improving the efficiency.

[0071] The above embodiments are only used to illustrate the technical concept and features of the present invention, and their purpose is to enable those skilled in the art to understand the content of the present invention and implement it, and cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit and essence of the present invention should be covered within the protection scope of the present invention.

Claims

1. An array-type electrohydraulic shock wave controllable focusing device, comprising a housing, an energy storage electrical appliance, electrodes, and a energy transmission liquid, characterized in that, The energy transmission liquid is disposed within the housing, and the electrodes are immersed in the energy transmission liquid; the electrodes include a negative electrode having a T-shaped structure and a positive electrode matrix composed of m equally spaced linearly arranged positive electrodes, and each of the positive electrodes forms an electrode element with the negative electrode; the positive electrode matrix is electrically connected to the array switch, the array switch is electrically connected to the energy storage electrical appliance, and the array switch is also electrically connected to the microprocessor, and the microprocessor is used to store the time delay of the positive electrode matrix. The spatial coordinates of the m-th electrode element are (x m , y m , z m ). The focusing position of the controllable shock wave is within the near field of the array. Taking the center of the array as the coordinate origin, the distance between the focusing position and the coordinate origin is r, the azimuth angle is θ, and the elevation angle is Then the distance between the m-th positive electrode and the focusing position can be expressed as: The received signal of the shock wave signal discharged by the m-th electrode at the focal position can be expressed as: where t is the time coordinate, A is the discharge voltage amplitude constant of the energy storage electrical appliance, w is the angular frequency of the shock wave signal, k = 2π / λ, and λ is the wavelength of the shock wave signal. According to the principle of near-field beamforming, a shaping filter \(h(t)\) of order \(L\) is used for near-field focusing processing. Then, the shock wave signals of each electrode received at the focusing position are as follows: m (t) The near-field beamforming formula can obtain the near-field beamforming filter h m (t); The electrode time delay corresponding to the m-th electrode can be expressed as: After the shock wave signals of each electrode element received at the focal position are controlled by time delay, controllable focusing of the shock wave is achieved, which can be expressed as: where the function δ is the unit impulse function, which is used to control the time delay and output to control the m-th electrode element.

2. The array-type electrohydraulic shock wave controllable focusing device according to claim 1, characterized in that The energy storage electrical appliance is a high-voltage discharge capacitor.

3. The array-type liquid-electric shock wave controllable focusing device according to claim 1, characterized in that The housing is provided with a water inlet and a water outlet.

4. The array-type liquid-electric shock wave controllable focusing device according to claim 1, wherein The energy transmission liquid is clean water.

5. A control method for an array-type liquid-electric shock wave controllable focusing device, applicable to the controllable focusing device according to any one of claims 1-4, characterized in that, It includes the following steps: Step 1: Time delay generation, calculating and generating the electrode time delay corresponding to each focal position of the shock wave, and storing the electrode time delay in the microprocessor. Step 2: Focal position input, determining the shock wave focal position according to the treatment requirement and inputting it into the microprocessor. Step 3: Controlling the selective energization time of each positive electrode in the electrode array, retrieving the corresponding electrode time delay in the microprocessor according to the input shock wave focal position, and the microprocessor controls the energization time of each electrode according to the electrode time delay. Step 4: Each electrode generates a shock wave, and the shock waves generated by each electrode are aligned and focused in time through time delay, so as to achieve the shock wave focusing at the corresponding focal position.

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