An ultrasonic powered external counterpulsation device

Abstract

The present invention belongs to the technical field of extracorporeal counterpulsation, in particular to an extracorporeal counterpulsation device based on ultrasonic power, comprising a binding belt, a piezoelectric stator, a piezoelectric rotor, and a displacement amplifier; the piezoelectric stator comprises a first metal silicone and piezoelectric ceramics arranged at intervals on one side of the first metal silicone; the piezoelectric rotor comprises a second metal silicone and a plastic layer arranged on one side of the second metal silicone, the plastic layer being in contact with a side of the first metal silicone away from the piezoelectric ceramic; one end of the displacement sensor is fixedly connected to the second metal silicone, and the other end is fixedly connected to the other end of the binding belt, and a voltage source with a phase difference of 90° is applied to the adjacently arranged piezoelectric ceramics to achieve tightening and loosening of the binding belt on the patient's limbs; compared with a traditional mechanical extracorporeal counterpulsation device, the extracorporeal counterpulsation device provided by the present invention can generate high torque without power conversion through gears, and can directly drive the tightening or loosening of the binding belt.

Description

Technical Field

[0001] The invention belongs to the technical field of external counterpulsation, in particular to an external counterpulsation device based on ultrasonic power. Background Art

[0002] EECP is a method of non-invasive external compression of the lower body to reduce or eliminate angina symptoms and improve the hypoxia-ischemia state of important organs of the body. It is also a medical device used to prevent and treat cardiovascular and cerebrovascular diseases. Traditional EECP devices use air bags wrapped around the limbs and buttocks to inflate and pressurize the air bags during the diastole of the heart, prompting blood from the limb arteries and veins to return to the heart, significantly increasing diastolic pressure, improving blood perfusion of important organs such as the heart and brain, and reducing cardiac afterload; during the systole of the heart, the air bags are quickly deflated, the pressure is relieved, and the systolic pressure in the aorta is reduced, minimizing the resistance of the heart's ejection phase, and accelerating the blood flow to the distal end, thereby achieving the counterpulsation effect.

[0003] However, the traditional airbag inflation and pressurization method does not accurately control the extrusion force and has a slow speed response. Specifically, the airbag inflation and pressurization process is a gas compression transfer process, that is, the movement of gas in the gas path is a pressure equalization process under the condition of pressure difference. Compared with contact-type mechanical extrusion, this process has a slower response speed; at the same time, since the gas path pressure change is nonlinear, the control is more complicated. Summary of the invention

[0004] The purpose of the present invention is to overcome the deficiencies in the prior art and provide an ultrasonic powered external counterpulsation device.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] An ultrasonic powered external counterpulsation device, comprising:

[0007] A binding belt is tied around the patient's limb, one end of the binding belt is connected to a cover body with a containing space, and the opening of the cover body points away from the end of the binding belt;

[0008] A piezoelectric stator is disposed in the cover body and includes a first metal silicone and piezoelectric ceramics arranged at intervals on one side of the first metal silicone;

[0009] A piezoelectric rotor, comprising a second metal silicone and a plastic layer disposed on one side of the second metal silicone, wherein the plastic layer is in contact with a side of the first metal silicone away from the piezoelectric ceramic;

[0010] a displacement amplifier, one end of which is fixedly connected to the second metal silicone and the other end of which is fixedly connected to the other end of the binding belt;

[0011] A voltage source with a phase difference of 90° is applied to adjacently arranged piezoelectric ceramics to achieve tightening and loosening of the binding belt on the patient's limb.

[0012] Preferably, the adjacently arranged piezoelectric ceramics are driven by voltage sources Csin(wt) and Ccos(wt) respectively, or by voltage sources Csin(wt) and -Ccos(wt) respectively to achieve tightening and loosening of the binding belt on the patient's limb;

[0013] Where C is the voltage amplitude, w is the angular frequency, and t is the time.

[0014] Preferably, the piezoelectric ceramics are grouped in pairs, with a total of 30 groups; and the amplification factor of the displacement amplifier is 10 times.

[0015] Preferably, a flat water bag is provided on the inner side of the cover body.

[0016] Compared with the prior art, the present invention has the following technical effects:

[0017] 1. Compared with the traditional external counterpulsation device, the ultrasonic-powered external counterpulsation device provided by the present invention has a greatly reduced volume, a greatly reduced weight of the entire external counterpulsation device, and a greatly increased system response speed;

[0018] 2. Compared with the traditional mechanical external counterpulsation device, the ultrasonic-powered external counterpulsation device provided by the present invention can generate high torque without the need for gears to convert power, and can directly drive the tightening or loosening of the binding belt tied around the patient's limbs;

[0019] 3. The ultrasonic powered EVCP device provided by the present invention can maintain high torque and easily achieve precise positioning, and can stop and remain at the corresponding position when the voltage source disappears;

[0020] 4. The ultrasonic-powered EVCP device provided by the present invention has a compact driving structure, and EVCP devices of different shapes can be designed, which is very flexible in design.

[0021] 5. The ultrasonic-powered extracorporeal counterpulsation device provided by the present invention has a simple structure and is quiet and noiseless during use.

[0022] Other features and advantages of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A top view of an ultrasonic powered external counterpulsation device provided by the present invention;

[0024] Figure 2 for Figure 1Sectional view of section AA;

[0025] Figure 3 for Figure 2 A magnified schematic diagram of position B in the middle;

[0026] Figure 4 It is a schematic diagram of the principle of relative movement between the piezoelectric stator and the piezoelectric rotor in the present invention;

[0027] Figure 5 It is a schematic diagram of the vibration generated by the piezoelectric stator generating a traveling wave with a toothed structure after the piezoelectric ceramic generates mechanical vibration through coupling;

[0028] Figure 6 Schematic diagram of the motion state of the piezoelectric stator at different times;

[0029] Figure 7 It is the principle diagram of displacement amplifier;

[0030] Explanation of the numbers in the figure: 10 - binding belt, 101 - locking piece, 20 - cover, 30 - piezoelectric stator, 31 - first metal silicone, 32 - piezoelectric ceramic, 40 - piezoelectric rotor, 41 - second metal silicone, 42 - plastic layer, 50 - displacement amplifier. DETAILED DESCRIPTION

[0031] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with specific drawings.

[0032] Combination Figure 1 , 2 As shown in Figure 3, the present invention provides an ultrasonic-powered external counterpulsation device, comprising a strap 10, a piezoelectric stator 30, a piezoelectric rotor 40 and a displacement amplifier 50. The strap 10 is tied around the patient's limbs, and one end of the strap is connected to a cover 20 with a storage space, and the opening of the cover 20 points to the end away from the strap 10; the piezoelectric stator 30 is arranged in the cover 20, and the piezoelectric stator 30 includes a first metal silicone 31 and a piezoelectric ceramic 32 arranged at intervals on one side of the first metal silicone 31; the piezoelectric rotor 40 includes a second metal silicone 41 and a plastic layer 42 arranged on one side of the second metal silicone 41, and the plastic layer 42 is attached to the side of the first metal silicone 31 away from the piezoelectric ceramic 32; one end of the displacement amplifier 50 is fixedly connected to the second metal silicone 41, and the other end is fixedly connected to the other end of the strap 10, and the other end of the strap 10 is relative to the end connected to the cover 20. A voltage source with a phase difference of 90° is applied to adjacently arranged piezoelectric ceramics 32 to achieve tightening and loosening of the binding belt 10 on the patient's limb.

[0033] As a specific embodiment of the present invention, adjacently arranged piezoelectric ceramics 32 are driven by voltage sources Csin(wt) and Ccos(wt) respectively, or by voltage sources Csin(wt) and -Ccos(wt) respectively to achieve tightening and loosening of the strap 10 on the patient's limb; wherein C is the voltage amplitude, w is the angular frequency, and t is the time.

[0034] The working principle of the external counterpulsation device provided by the present invention is:

[0035] The piezoelectric ceramics 32 with opposite polarization directions are sequentially bonded and fixed on the first metal silicone 31. When an alternating voltage is applied to the piezoelectric ceramics 32, the piezoelectric ceramics will produce alternating expansion and contraction deformations. Under certain frequency and voltage conditions, a standing wave as shown in the figure will be generated on the first metal silicone 31, which can be expressed by the equation:

[0036] ;

[0037] The amplitude of standing waves generated by two adjacent piezoelectric ceramics 32, such as A and B, is the same as ε0, and the two are 90° apart in time and space. The equations are:

[0038] ;

[0039] In the first metal silica gel 31, the above two standing waves are combined into a row wave:

[0040] ;

[0041] Combination Figure 4 As shown, the thickness of the first metal silicone 31 is set to h. If the position of any point P on the surface of the first metal silicone 31 when not bent is P0, the displacement from P0 to P in the y direction is:

[0042] ;

[0043] Wherein: θ is the bending angle of the first metal silicone 31 during vibration;

[0044] Since the amplitude of the traveling wave is much smaller than the wavelength of the traveling wave, the bending angle θ of the first metal silicone 31 is very small, so the displacement in the y direction is approximately:

[0045] ;

[0046] The displacement from P0 to P in the x direction is: ;

[0047] again: ;

[0048] so: ;

[0049] (Equation of an ellipse);

[0050] Any point P on the surface of the first metal silicone 31 moves along an elliptical trajectory. This movement causes the particle on the surface of the first metal silicone 31 to generate a driving force on the moving body, and the moving direction of the moving body is opposite to the direction of the traveling wave.

[0051] Combination Figure 5 As shown, the mechanical vibration generated by the piezoelectric ceramic 32 generates vibration generated by the traveling wave tooth-shaped structure on the first metal silicone 31 after coupling.

[0052] Another example Figure 6 As shown, the four curves represent the motion state of the piezoelectric stator 30 at different times from light to dark. The darker the color, the later the time. It can be seen that the traveling wave moves from left to right. Figure 6 The middle tooth-shaped structure moves in an elliptical path of 1-2-3-4, and its movement direction at the vertex 1 is from right to left. The pulsation of the vertex 1 from right to left causes the piezoelectric rotor 40 above to move in the opposite direction of the wave.

[0053] That is to say, through the technical solution of the present invention, the high-frequency voltage with a phase difference of 90° in electrical angle applied to adjacent piezoelectric ceramics 32 is converted into multiple groups of standing waves in the first metal silicone 31, and the multiple groups of standing waves are combined into a traveling wave traveling along the first metal silicone 31, so that the particles on the surface of the piezoelectric stator 30 form ultrasonic micro-vibrations with a certain motion trajectory. The motion trajectory is usually an elliptical trajectory, and its amplitude is generally several microns. This micro-vibration causes friction between the piezoelectric stator 30 and the piezoelectric rotor 40, thereby causing the piezoelectric rotor 40 to move in a certain direction.

[0054] In order to further convert the movement of the piezoelectric rotor 40 into the power for tightening or loosening the strap 10, a displacement amplifier 50 is connected to the piezoelectric rotor 40. The function of the displacement amplifier 50 is to convert the tiny movement of the piezoelectric rotor 40 into a macroscopic displacement, thereby tightening the strap 10 to reduce the space it is wrapped around the patient's limb, or loosening the strap 10 to increase the space it is wrapped around the patient's limb, thereby achieving a counterpulsation therapeutic effect. Specifically, the displacement amplifier 50 is a micro-vibration displacement amplification structure of a telescopic material, including a magnetostrictive or electrostrictive body, a displacement output rod and a rigid structural support. The principle of the displacement amplifier 50 is as follows Figure 7 As shown; wherein A is the amplification factor of the displacement amplifier 50, A1 is the first-stage displacement amplifier, and A2 is the second-stage displacement amplifier;

[0055] A=A1×A2;

[0056] A1=1+l2 / l1, A2=1+l4 / l3, substituting the specific dimensions l1=4mm, l2=6mm, l3=4mm, l4=12mm, the amplification factor A of the displacement amplifier 50 is 10.

[0057] Specifically, in the present invention, the piezoelectric ceramics 32 are grouped in pairs, with a total of 30 groups. Each time the piezoelectric contraction friction of the piezoelectric ceramics 32 drives the piezoelectric rotor 40 to move horizontally by 100 microns, which is amplified 10 times by the displacement amplifier 50, that is, the displacement distance is 1000 microns. By setting 30 groups, the displacement each time is 3 cm, that is, the contraction is 3 cm.

[0058] In the present invention, in order to facilitate binding of the patient's limbs, the binding belt 10 is divided into two sections, and a locking piece 101 is provided between the two sections of the binding belt 10 for locking and fixing the binding state on the patient's limbs. As a specific implementation of the locking piece 101, the locking piece 101 can be selected from nylon buckles, buckles or Velcro that are easy to disassemble.

[0059] In the present invention, the binding belt 10 needs to be made of a flexible non-stretchable material to ensure a quick response during tightening and loosening. Specifically, the binding belt 10 can be made of nylon cloth.

[0060] The plastic layer 42 needs to provide greater friction, and for example, phenolic resin materials, silicone rubber, and soft polyurethane can be selected. More preferably, the side of the plastic layer 42 adjacent to the first metal silicone 31 is processed to form a rough surface with texture to improve friction.

[0061] The cover body 20 is made of ABS engineering material.

[0062] The first metal silicone 31 and the second metal silicone 41 can be made of phosphor bronze, brass, stainless steel or titanium. Considering the cost performance, the first metal silicone 31 is preferably made of stainless steel or brass.

[0063] The piezoelectric ceramic 32 is made of lead zirconate titanate binary piezoelectric ceramic, which is currently the most widely used, has the widest range of uses, the largest output, and mature technology.

[0064] According to the present invention, a flat water bag is disposed inside the cover body 20, so that the cover body 20 can have a cooling function.

[0065] The ultrasonic-powered extracorporeal counterpulsation device provided by the present invention, when used, is to wrap the binding belt 10 around the patient's limbs and fix them with the locking piece 101. Then, the patient's electrocardiogram signal and arterial pressure signal are collected, and the trigger point, that is, the compression and release timing, is obtained after processing, and sent to the circuit control system of the piezoelectric ceramic 32. The circuit control system controls the application of the voltage source on the piezoelectric ceramic 32, thereby generating a standing wave on the first metal silica gel 31, and further drives the movement of the piezoelectric rotor 40, which is converted into a macroscopic movement of tightening or releasing the binding belt 10 through the displacement amplifier 50, and pressure is applied or released on the patient's limbs to achieve the therapeutic effect of counterpulsation.

[0066] The above-mentioned EVCP device avoids the drawbacks of pneumatic EVCP devices in the prior art that use large air compressors and solenoid valves to squeeze the patient's limbs. It has low noise and no vibration, making the patient more comfortable during the EVCP treatment process. In addition, the EVCP device based on ultrasonic power avoids the drawbacks of mechanical EVCP that the device is large in size and not compact enough when using transmission structures such as gears. Moreover, the EVCP device based on ultrasonic power can maintain high torque at all times and can easily achieve precise positioning, that is, it stays and remains in the corresponding position after the voltage source disappears.

[0067] The above shows and describes the basic principles, main features and characteristics of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of the present invention to be protected is defined by the attached claims and their equivalents.

Claims

1. An ultrasonic powered external counterpulsation device, characterized in that: include: A binding belt (10) is tied around a patient's limb, one end of the binding belt (10) is connected to a cover body (20) having a containing space, and an opening of the cover body (20) points away from the end of the binding belt (10); A piezoelectric stator (30) is arranged in the cover body (20), comprising a first metal silicone (31) and a piezoelectric ceramic (32) arranged at intervals on one side of the first metal silicone (31); A piezoelectric rotor (40), comprising a second metal silicone (41) and a plastic layer (42) arranged on one side of the second metal silicone (41), wherein the plastic layer (42) is in contact with a side of the first metal silicone (31) away from the piezoelectric ceramic (32); A displacement amplifier (50), one end of which is fixedly connected to the second metal silicone (41), and the other end of which is fixedly connected to the other end of the binding belt (10); Wherein, a voltage source with a phase difference of 90° is applied to adjacently arranged piezoelectric ceramics (32) to achieve tightening and loosening of the binding belt (10) on the patient's limb; The adjacently arranged piezoelectric ceramics (32) are driven by voltage sources Csin(wt) and Ccos(wt) respectively, or driven by voltage sources Csin(wt) and -Ccos(wt) respectively, so as to achieve tightening and loosening of the binding belt (10) on the patient's limb; Where C is the voltage amplitude, w is the angular frequency, and t is the time; The working principle of the external counterpulsation device is: Piezoelectric ceramics (32) with opposite polarization directions are sequentially bonded and fixed on the first metal silicone (31). When an alternating voltage is applied to the piezoelectric ceramic (32), the piezoelectric ceramic will produce alternating expansion and contraction deformations. Under certain frequency and voltage conditions, standing waves will be generated on the first metal silicone (31), which can be expressed as follows: ； The amplitude of standing waves generated by two adjacent piezoelectric ceramics (32), such as A and B, is the same as ε0, and the two are 90° apart in time and space. The equations are: ； In the first metal silica gel (31), the above two standing waves are combined into a row wave: ； The thickness of the first metal silicone (31) is set to h. If the position of any point P on the surface of the first metal silicone (31) when not bent is P0, then the displacement from P0 to P in the y direction is: ； Wherein: θ is the bending angle of the first metal silicone (31) during vibration; Since the amplitude of the traveling wave is much smaller than the wavelength of the traveling wave, the bending angle θ of the first metal silicone (31) is very small, so the displacement in the y direction is approximately: ； The displacement from P0 to P in the x direction is: ; again: ; so: ; (Equation of an ellipse); Any point P on the surface of the first metal silicone (31) moves along an elliptical trajectory, and this movement causes the particle on the surface of the first metal silicone (31) to generate a driving force on the moving body, and the moving direction of the moving body is opposite to the direction of the traveling wave; The mechanical vibration generated by the piezoelectric ceramic (32) is coupled to generate vibration generated by the traveling wave tooth-shaped structure on the first metal silica gel (31); As time changes, the traveling wave moves from left to right, and the piezoelectric stator (30) moves along a counterclockwise elliptical path. The direction of movement at the upper vertex of the elliptical path is from right to left. The upper vertex pulsates from right to left, causing the upper piezoelectric rotor (40) to move in the opposite direction of the wave. The high-frequency voltages applied to adjacent piezoelectric ceramics (32) with a phase difference of 90° in electrical angle are converted into a plurality of groups of standing waves in the first metal silica gel (31), and the plurality of groups of standing waves are synthesized into a traveling wave that travels along the first metal silica gel (31), so that the particles on the surface of the piezoelectric stator (30) form an ultrasonic microscopic vibration with a certain motion trajectory, and the motion trajectory is usually an elliptical trajectory, and the amplitude is generally several micrometers. This microscopic vibration generates friction between the piezoelectric stator (30) and the piezoelectric rotor (40), so that the piezoelectric rotor (40) moves in a certain direction; In order to further convert the movement of the piezoelectric rotor (40) into power for tightening or loosening the binding belt (10), a displacement amplifier (50) is connected to the piezoelectric rotor (40). The function of the displacement amplifier (50) is to convert the micro-movement of the piezoelectric rotor (40) into a macroscopic displacement, thereby tightening the binding belt (10) to reduce the space it wraps around the patient's limb, or loosening the binding belt (10) to increase the space it wraps around the patient's limb, thereby achieving a counterpulsation treatment effect. Specifically, the displacement amplifier (50) is a micro-vibration displacement amplification structure of a telescopic material, comprising a magnetostrictive or electrostrictive body, a displacement output rod and a rigid structural support. Wherein, A is the amplification factor of the displacement amplifier (50), A1 is the first-stage displacement amplifier, and A2 is the second-stage displacement amplifier; A=A1×A2; A1=1+l2 / l1, A2=1+l4 / l3, substituting the specific dimensions l1=4mm, l2=6mm, l3=4mm, l4=12mm, the amplification factor A of the displacement amplifier (50) is 10.

2. The ultrasonic powered external counterpulsation device according to claim 1, characterized in that: The piezoelectric ceramics (32) are grouped in pairs, with a total of 30 groups provided; the displacement amplifier (50) has an amplification factor of 10 times.

3. The ultrasonic powered external counterpulsation device according to claim 1, characterized in that: A flat water bag is provided on the inner side of the cover body (20).

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