Pulse detecting device and ultrasound diagnostic apparatus

Abstract

There is provided a pulse detecting device which resists fluctuations in the quality by locating an ultrasound transmitting piezoelectric element and an ultrasound receiving piezoelectric element with high precision. In the pulse detecting device, a detection sensitivity of the pulse is improved. A transmitting piezoelectric element and a receiving piezoelectric element are fixed onto a substrate by electrodes. The transmitting piezoelectric element is excited in response to an inputted drive voltage signal to generate an ultrasound and transmits the generated ultrasound to a living body. The receiving piezoelectric element receives an echo produced by reflecting the ultrasound transmitted into the living body by a blood flow of the living body and converts it into a voltage signal. A processing arithmetic unit compares the frequency of the ultrasound generated by the transmitting piezoelectric element with that of the echo received in the receiving piezoelectric element to thereby detect a pulse.

What is claimed is:  
     
         1 . A pulse detecting device comprising: 
 a transmitting piezoelectric element to transmit an ultrasound into a living body in response to an inputted drive signal;    a receiving piezoelectric element to receive an echo produced by reflecting the ultrasound by a blood flow of the living body;    a substrate to fix the transmitting piezoelectric element and the receiving piezoelectric element onto one surface;    a detection unit to detect a pulse in accordance with the ultrasound generated by the transmitting piezoelectric element and the echo; and    a feed portion provided on the substrate in order to apply the drive signal to the transmitting piezoelectric element,    wherein at least one surface of one of the transmitting piezoelectric element and the receiving piezoelectric element is fixed onto the substrate in the feed portion.    
     
     
         2 . A pulse detecting device comprising: 
 a transmitting piezoelectric element to transmit an ultrasound into a living body in response to an inputted drive signal;    a receiving piezoelectric element to receive an echo produced by reflecting the ultrasound by a blood flow of the living body;    a substrate to fix at least one of the transmitting piezoelectric element and the receiving piezoelectric element onto one surface; and    a detection unit to detect a pulse in accordance with the ultrasound generated by the transmitting piezoelectric element and the echo,    wherein a gap is produced between the substrate and at least one of the transmitting piezoelectric element and the receiving piezoelectric element.    
     
     
         3 . A pulse detecting device comprising: 
 a transmitting piezoelectric element to transmit an ultrasound into a living body in response to an inputted drive signal;    a receiving piezoelectric element to receive an echo produced by reflecting the ultrasound by a blood flow of the living body;    a substrate in which at least one of the transmitting piezoelectric element and the receiving piezoelectric element is provided on one surface; and    a support to support the substrate, in which the substrate is provided on a rear surface opposite to a surface that is in contact with the living body,    wherein a gap is produced between the support and the substrate.    
     
     
         4 . An ultrasound diagnostic apparatus comprising: 
 a transmitting piezoelectric element to transmit an ultrasound into a living body in response to an inputted drive signal;    a receiving piezoelectric element to receive an echo produced by reflecting the ultrasound by a diagnostic portion of the living body;    a substrate to fix the transmitting piezoelectric element and the receiving piezoelectric element onto one surface;    a detection unit to detect information with respect to the diagnostic portion from the ultrasound generated by the transmitting piezoelectric element and the echo; and    a feed portion to apply the drive signal to the transmitting piezoelectric element provided on the substrate,    wherein the transmitting piezoelectric element is fixed onto the substrate in the feed portion.    
     
     
         5 . An ultrasound diagnostic apparatus comprising: 
 a transmitting piezoelectric element to transmit an ultrasound into a living body in response to an inputted drive signal;    a receiving piezoelectric element to receive an echo produced by reflecting the ultrasound by a diagnostic portion of the living body;    a substrate to fix the transmitting piezoelectric element and the receiving piezoelectric element onto one surface;    a detection unit to detect information with respect to the diagnostic portion from the ultrasound generated by the transmitting piezoelectric element and the echo; and    a feed portion to apply the drive signal to the transmitting piezoelectric element provided on the substrate,    wherein at least one of a convex portion and a concave portion is provided in at least one of the substrate and the transmitting and receiving piezoelectric elements, and    a peripheral portion of at least one of the convex portion and the concave portion is fixed such that a gap is produced between the substrate and the transmitting and receiving piezoelectric elements.    
     
     
         6 . An ultrasound diagnostic apparatus according to  claim 4 , wherein at least one of a first protrusion to protrude from the substrate to the transmitting and receiving piezoelectric elements, a second protrusion to protrude from the feed portion to the transmitting and receiving piezoelectric elements, and a third protrusion to protrude from the transmitting and receiving piezoelectric elements to the feed portion, is provided.  
     
     
         7 . An ultrasound diagnostic apparatus according to  claim 5 , wherein at least one of a first protrusion to protrude from the substrate to the transmitting and receiving piezoelectric elements, a second protrusion to protrude from the feed portion to the transmitting and receiving piezoelectric elements, and a third protrusion to protrude from the transmitting and receiving piezoelectric elements to the feed portion, is provided.  
     
     
         8 . An ultrasound diagnostic apparatus according to  claim 4 , wherein the substrate is made of a material for attenuating the ultrasound.  
     
     
         9 . An ultrasound diagnostic apparatus according to  claim 5 , wherein the substrate is made of a material for attenuating the ultrasound.  
     
     
         10 . An ultrasound diagnostic apparatus according to  claim 4 , wherein the substrate is made of a porous material.  
     
     
         11 . An ultrasound diagnostic apparatus according to  claim 5 , wherein the substrate is made of a porous material.  
     
     
         12 . An ultrasound diagnostic apparatus according to  claim 4 , wherein a groove is provided in a portion of the substrate and the transmitting piezoelectric element and the receiving piezoelectric element are located sandwiching the groove on the substrate.  
     
     
         13 . An ultrasound diagnostic apparatus according to claim  5 , wherein a groove is provided in a portion of the substrate and the transmitting piezoelectric element and the receiving piezoelectric element are located sandwiching the groove on the substrate.  
     
     
         14 . An ultrasound diagnostic apparatus according to  claim 4 , wherein the substrate is divided, the transmitting piezoelectric element is located on one of the division substrates, and the receiving piezoelectric element is located on a division substrate different from the division substrate on which the transmitting piezoelectric element is located.  
     
     
         15 . An ultrasound diagnostic apparatus according to  claim 5 , wherein the substrate is divided, the transmitting piezoelectric element is located on one of the division substrates, and the receiving piezoelectric element is located on a division substrate different from the division substrate on which the transmitting piezoelectric element is located.  
     
     
         16 . An ultrasound diagnostic apparatus according to  claim 4 , wherein a resin layer is provided on a piezoelectric element locating surface of the substrate.  
     
     
         17 . An ultrasound diagnostic apparatus according to  claim 5 , wherein a resin layer is provided on a piezoelectric element locating surface of the substrate.  
     
     
         18 . An ultrasound diagnostic apparatus comprising: 
 a transmitting piezoelectric element to transmit an ultrasound to a diagnostic portion in response to an inputted drive signal;    a receiving piezoelectric element to receive an echo produced by reflecting the ultrasound by the diagnostic portion;    a substrate to fix the transmitting piezoelectric element and the receiving piezoelectric element onto one surface;    information obtaining means for obtaining information of the diagnostic portion from the ultrasound generated by the transmitting piezoelectric element and the echo; and    a support to support the substrate,    wherein a gap is produced between the support and the substrate.    
     
     
         19 . An ultrasound diagnostic apparatus according to  claim 18 , wherein the support is formed into a convex shape with respect to the substrate.  
     
     
         20 . An ultrasound diagnostic apparatus according to  claim 18 , wherein the substrate is made of a material for attenuating the ultrasound.  
     
     
         21 . An ultrasound diagnostic apparatus comprising: 
 a transmitting piezoelectric element to transmit an ultrasound into a living body in response to an inputted drive signal;    a receiving piezoelectric element to receive an echo produced by reflecting the ultrasound by the diagnostic portion of the living body;    a substrate in which the transmitting piezoelectric element and the receiving piezoelectric element are provided on one surface; and    a support to support the substrate, in which the substrate is provided on a rear surface opposite to a surface that is in contact with the living body,    wherein a gap is produced between the substrate and the support.    
     
     
         22 . An ultrasound diagnostic apparatus according to  claim 18 , wherein the transmitting piezoelectric element and the receiving piezoelectric element are fixed on respective separate substrates and the respective separate substrates are located on the same support.  
     
     
         23 . An ultrasound diagnostic apparatus according to  claim 21 , wherein the transmitting piezoelectric element and the receiving piezoelectric element are fixed on respective separate substrates and the respective separate substrates are located on the same support.  
     
     
         24 . An ultrasound diagnostic apparatus according to  claim 21 , wherein an acoustic impedance of the substrate is a value between that of the transmitting piezoelectric element and the receiving piezoelectric element and that of the living body.  
     
     
         25 . An ultrasound diagnostic apparatus according to  claim 24 , wherein the substrate has a thickness corresponding to substantially a quarter of a wavelength of the ultrasound generated by the transmitting piezoelectric element.  
     
     
         26 . An ultrasound diagnostic apparatus according to  claim 18 , wherein the support is a box type or has a comb teeth shape.  
     
     
         27 . An ultrasound diagnostic apparatus according to  claim 21 , wherein the support is a box type or has a comb teeth shape.  
     
     
         28 . An ultrasound diagnostic apparatus according to  claim 18 , wherein a material of the support is at least one of ceramics, plastic, and metal.  
     
     
         29 . An ultrasound diagnostic apparatus according to  claim 21 , wherein a material of the support is at least one of ceramics, plastic, and metal.  
     
     
         30 . An ultrasound diagnostic apparatus comprising: 
 a transmitting piezoelectric element to transmit an ultrasound to a diagnostic portion in response to an inputted drive signal;    a receiving piezoelectric element to receive an echo produced by reflecting the ultrasound by the diagnostic portion;    a substrate to fix the transmitting piezoelectric element and the receiving piezoelectric element onto one surface; and    information obtaining means for obtaining information of the diagnostic portion from the ultrasound generated by the transmitting piezoelectric element and the echo,    wherein an ultrasound attenuation portion to attenuate the propagation of the ultrasound is provided between the transmitting and receiving piezoelectric elements and the substrate.    
     
     
         31 . An ultrasound diagnostic apparatus according to  claim 30 , wherein the ultrasound attenuation portion is divided between the transmitting piezoelectric element and the receiving piezoelectric element.  
     
     
         32 . An ultrasound diagnostic apparatus according to  claim 30 , wherein a material of the ultrasound attenuation portion is conductive rubber.  
     
     
         33 . An ultrasound diagnostic apparatus according to  claim 18 , wherein an ultrasound attenuation portion for attenuating the propagation of the ultrasound is provided between the support and the substrate.  
     
     
         34 . An ultrasound diagnostic apparatus according to  claim 21 , wherein an ultrasound attenuation portion for attenuating the propagation of the ultrasound is provided between the support and the substrate.  
     
     
         35 . An ultrasound diagnostic apparatus according to claim  18 , wherein a depth of the gap in a transmitting and receiving direction of the ultrasound is equal to or larger than a wavelength ë of the ultrasound.  
     
     
         36 . An ultrasound diagnostic apparatus according to  claim 21 , wherein a depth of the gap in a transmitting and receiving direction of the ultrasound is equal to or larger than a wavelength ë of the ultrasound.  
     
     
         37 . An ultrasound diagnostic apparatus according to  claim 18 , wherein an area of the gap opposite to the substrate is larger than that of an ultrasound transmitting and receiving surface of the transmitting and receiving piezoelectric elements.  
     
     
         38 . An ultrasound diagnostic apparatus according to  claim 21 , wherein an area of the gap opposite to the substrate is larger than that of an ultrasound transmitting and receiving surface of the transmitting and receiving piezoelectric elements.