Measuring device

Abstract

A measuring device having a first space for pressurizing an object to be pressurized and a second space independent of the first space. The measuring device is provided with a first exhaust valve that closes or opens a communication port for communication between the first space and another space. The open / closed state of the first exhaust valve changes depending on a pressure difference between the first space and the second space.

Description

Measuring equipment

[0001] The present invention relates to a measurement device.

[0002] Among measuring devices such as blood pressure monitors, there are known so-called pressurizing measuring devices that measure blood pressure during pressurization, rather than during the depressurization process after pressurization. In pressurizing measuring devices, it is necessary to rapidly release the pressurized air in the cuff when pressurization stops. For example, there are known measuring devices that use a solenoid valve to rapidly release the pressurized air.

[0003] Japanese Patent Application Laid-Open No. 2018-171311

[0004] The provision of a solenoid valve complicates the structure of the measuring device, increases manufacturing costs and power consumption, and hinders miniaturization of the measuring device.

[0005] One aspect of the present invention is to provide a measurement device that can be simplified in structure.

[0006] In one aspect, the measurement device has a first space for pressurizing a pressurized object and a second space independent of the first space. The measurement device also includes a first exhaust valve for closing or opening a communication port connecting the first space with another space. The open / closed state of the first exhaust valve changes depending on the pressure difference between the first space and the second space.

[0007] According to one aspect, the structure of the measurement device can be simplified.

[0008] FIG. 1 is a perspective view showing an example of the overall configuration of a measurement device according to an embodiment. FIG. 2 is a cross-sectional view showing an example of a pump according to a first embodiment. FIG. 3 is a cross-sectional view showing an example of a pressure regulating mechanism according to the first embodiment. FIG. 4 is a cross-sectional view showing an example of an intake state of the pressure regulating mechanism according to the first embodiment. FIG. 5 is a cross-sectional view showing an example of an exhaust state of the pressure regulating mechanism according to the first embodiment. FIG. 6 is a cross-sectional view showing an example of a pump according to a second embodiment. FIG. 7 is a cross-sectional view showing an example of a pressure regulating mechanism according to the second embodiment. FIG. 8 is a cross-sectional view showing an example of an intake state of the pressure regulating mechanism according to the second embodiment. FIG. 9 is a cross-sectional view showing an example of an exhaust state of the pressure regulating mechanism according to the second embodiment. FIG. 10 is an enlarged cross-sectional view showing an example of the positional relationship between a first exhaust valve and an opening according to a first modified example. FIG. 11 is an enlarged cross-sectional view showing an example of the operation of the first exhaust valve in the intake state according to the first modified example. FIG. 12 is an enlarged cross-sectional view showing another example of the operation of the first exhaust valve in the intake state according to the first modified example. FIG. 13 is an enlarged cross-sectional view showing an example of the operation of the first exhaust valve in the exhaust state according to the first modified example. FIG. 14 is an enlarged cross-sectional view showing another example of the operation of the first exhaust valve in the exhaust state in the second modified example.

[0009] Hereinafter, embodiments of the measuring device disclosed herein will be described in detail with reference to the drawings. Note that the dimensional relationships and ratios of elements in the drawings may differ from reality. The drawings may also include portions with different dimensional relationships and ratios. Furthermore, in the following embodiments and modifications, the same components as those shown in the previously described drawings will be designated by the same reference numerals, and redundant description will be omitted.

[0010] First, the measurement device in each embodiment will be described with reference to Fig. 1. Fig. 1 is a perspective view showing an example of the overall configuration of the measurement device in each embodiment. As shown in Fig. 1, the measurement device 1 in each embodiment is, for example, an electronic blood pressure monitor, and includes a cuff 2, a main body 3, and a tube 4 connecting the cuff 2 and the main body 3. The main body 3 also includes a pump unit 5 and a control unit 6. The cuff 2 is an example of an object to be pressurized.

[0011] The pump unit 5 of the main body 3 supplies fluid to the cuff 2 via the tube 4. In each embodiment, for example, air is supplied as the fluid. The control unit 6 of the main body 3 controls, for example, starting and stopping the pump unit 5.

[0012] The cuff 2 is attached to a measurement site such as the wrist of a subject. The cuff 2 pressurizes the measurement site with air supplied from the main body 3. In each embodiment, the air supplied to the cuff 2 is discharged only through the tube 4. The air supplied to the cuff 2 is discharged through the tube 4 in response to the operation of the pump unit 5, which will be described later.

[0013] [First Embodiment] Next, a pump according to the first embodiment will be described. FIG. 2 is a cross-sectional view showing an example of a pump according to the first embodiment. As shown in FIG. 2, the pump unit 5 includes a drive mechanism 80, a swing mechanism 90, a pair of pressure adjustment mechanisms 11 and 12, and a pair of outlets 57 and 58. The number of pressure adjustment mechanisms included in the pump unit 5 is not limited to two, and may be one, or three or more. Hereinafter, when the pair of pressure adjustment mechanisms 11 and 12 are not to be distinguished from each other, they may be referred to as pressure adjustment mechanism 10. When the pair of outlets 57 and 58 are not to be distinguished from each other, they may be referred to as outlet 59.

[0014] The drive mechanism 80 is an operating unit that causes the swing mechanism 90 to swing, and is composed of, for example, a pair of actuators 81 and 82. The drive mechanism 80 starts or stops its operation, for example, based on a control signal sent from the control unit 6. The actuators 81 and 82 are vibration actuators that use, for example, a solenoid or a motor. Known vibration actuators can be used, such as those that use a piezoelectric element or those that utilize the resonance of an elastic body.

[0015] 2 includes, for example, a shaft 91 and a swinging body 92. The swinging body 92 swings in the up-and-down direction in the figure with the shaft 91 as the swinging axis, thereby pressing against a pressing portion of the pressure adjustment mechanism 10, which will be described later.

[0016] The pressure adjustment mechanism 10 pressurizes the cuff 2 by supplying air to the cuff 2 through the outlet 59 and the tube 4, and depressurizes the cuff 2 by discharging the air supplied to the cuff 2. The pair of pressure adjustment mechanisms 11 and 12 are both connected to the cuff 2 through the tube 4.

[0017] Fig. 3 is a cross-sectional view showing an example of the pressure regulating mechanism according to the first embodiment. Note that Fig. 3 shows a state in which neither pressure nor pressure is applied. As shown in Fig. 3, the pressure regulating mechanism 10 according to the first embodiment includes first pressurizing units 20 and 30, a first space 52, a first exhaust valve 60, and a pressure adjusting unit 70. The two first pressurizing units 20 and 30 are connected to the same first space 52.

[0018] 3, the first pressurizing unit 20 includes a movable unit 21, a sealed space 22, pressing units 23 and 24, an intake port 25, an intake valve 26, and a third exhaust valve 27. The movable unit 21 constitutes a part of the sealed space 22. The movable unit 21 changes its position and inclination in conjunction with the pressing units 23 and 24, thereby changing the volume of the sealed space 22. The movable unit 21 is a diaphragm made of a flexible material such as rubber.

[0019] The sealed space 22 repeatedly takes in and exhausts air as its volume increases and decreases. When the volume of the sealed space 22 increases, air is supplied to the sealed space 22 via the air intake port 25 and the air intake valve 26. When the volume of the sealed space 22 decreases, air is supplied to the first space 52 via the third exhaust valve 27.

[0020] The pressing portions 23 and 24 change the position and inclination of the movable portion 21 in conjunction with the swinging body 92. For example, when the swinging body 92 shown in FIG. 2 swings in the direction indicated by arrow D1, the pressing portions 23 and 24 push up the movable portion 21 of the first pressurizing portion 20. This reduces the volume of the sealed space 22. Furthermore, when the swinging body 92 shown in FIG. 2 swings in the direction indicated by arrow D2, air is supplied to the sealed space 22 of the first pressurizing portion 20 via the air intake port 25 and the air intake valve 26. As a result, the pressing portions 23 and 24 are pushed down by the movable portion 21.

[0021] The air intake port 25 connects the sealed space 22 to another space, such as the outside of the device. The air intake valve 26 is, for example, a check valve, and allows air to flow from the air intake port 25 to the sealed space 22 while restricting air flow from the sealed space 22 to the air intake port 25. The third exhaust valve 27 is provided between the sealed space 22 and the first space 52. The third exhaust valve 27 is also, for example, a check valve, and allows air to flow from the sealed space 22 to the first space 52 while restricting air flow from the first space 52 to the sealed space 22. The air intake valve 26 and the third exhaust valve 27 supply air from another space to the first space 52 via the sealed space 22.

[0022] 3 , the first pressurizing unit 30 includes the movable unit 21, the sealed space 22, the pressing units 23 and 24, the intake port 25, the intake valve 26, and the third exhaust valve 27, as well as a second exhaust valve 38. Similar to the third exhaust valve 27 of the first pressurizing unit 20, the third exhaust valve 27 of the first pressurizing unit 30 is also provided between the sealed space 22 of the first pressurizing unit 30 and the first space 52.

[0023] The second exhaust valve 38 is provided between the sealed space 22 and a second space 72 of the pressure adjustment unit 70, which will be described later. The second exhaust valve 38 is also, for example, a check valve, and allows air to flow from the sealed space 22 to the second space 72, while restricting air from the second space 72 to the sealed space 22. As a result, the first pressurizing unit 30 supplies air to the first space 52 and also to the second space 72.

[0024] As shown in Fig. 3 , the first pressurizing unit 30 and the first pressurizing unit 20 in the first embodiment are disposed at positions facing each other in the direction in which the oscillating body 92 extends, with the shaft 91 sandwiched between them. That is, when the oscillating body 92 shown in Fig. 2 oscillates in the direction indicated by arrow D1, air is supplied to the sealed space 22 of the first pressurizing unit 20, while air is supplied from the sealed space 22 of the first pressurizing unit 30 to the first space 52. Conversely, when the oscillating body 92 shown in Fig. 2 oscillates in the direction indicated by arrow D2, air is supplied from the sealed space 22 of the first pressurizing unit 20 to the first space 52, while air is supplied to the sealed space 22 of the first pressurizing unit 30. In this way, air is continuously supplied from the first pressurizing units 20 and 30 to the first space 52.

[0025] The outlet 59 connects the first space 52 to the tube 4. The pair of outlets 57 and 58 are provided corresponding to the pair of pressure adjustment mechanisms 11 and 12, respectively. That is, the first space 52 in the pressure adjustment mechanism 11 is connected to the cuff 2 via the outlet 57 and the tube 4. Similarly, the first space 52 in the pressure adjustment mechanism 12 is connected to the cuff 2 via the outlet 58 and the tube 4. As a result, air is supplied to the cuff 2 from both of the pair of pressure adjustment mechanisms 11 and 12.

[0026] In the first embodiment, air is supplied to the first space 52 of the pressure adjustment mechanism 10 from the first pressurizer 20 and the first pressurizer 30. In the first embodiment, the first space 52 and the cuff 2 form a sealed space when a first exhaust valve 60, which will be described later, is in a closed state. In this case, the air supplied to the first space 52 is supplied to the cuff 2 via the outlet 59 and the tube 4, thereby pressurizing the cuff 2.

[0027] On the other hand, when the first exhaust valve 60 is in an open state, air in the first space 52 is discharged from the first exhaust valve 60 to the other spaces. At this time, air is also discharged from the cuff 2 connected via the outlet 59 and the tube 4 through the first exhaust valve 60. In the first embodiment, the air pressure in the first space 52 and the cuff 2 increases in response to pressurization by the first pressurizer 20 and the first pressurizer 30, with the air pressure in the other spaces as the lower limit. Note that hereinafter, the first exhaust valve 60 in a closed state may be referred to as the first exhaust valve 60c, and the first exhaust valve 60 in an open state may be referred to as the first exhaust valve 60o.

[0028] The pressure adjusting unit 70 shown in Fig. 3 includes a second space 72 and an air leak valve 79. The second space 72 is a space independent of the first space 52. The second space 72 is not a sealed space, but communicates with other spaces via the air leak valve 79, and air constantly leaks into the other spaces.

[0029] In the first embodiment, air is supplied to the second space 72 from the first pressurizing unit 30 shown in Fig. 3 via the second exhaust valve 38. The amount of air supplied by the first pressurizing unit 30 is greater than the amount of air leaking from the air leak valve 79. That is, in the first embodiment, the air pressure in the second space 72 increases in response to pressurization by the first pressurizing unit 30, with the air pressure in the other spaces being the lower limit. In this case, as will be described later, the second space 72 is pressurized by the first pressurizing unit 30, so that the internal air pressure becomes higher than the internal air pressure of the first space 52.

[0030] In the first embodiment, when the pressurization by the first pressurizing unit 30 stops, the air supplied into the second space 72 leaks out through the air leak valve 79 into the other spaces. As a result, the air pressure in the second space 72 rapidly approaches the air pressure in the other spaces. As a result, as will be described later, the air pressure in the second space 72 becomes lower than the air pressure in the first space 52.

[0031] The first exhaust valve 60 closes or opens the first space 52 to another space, such as the outside of the device. The first exhaust valve 60 is provided, for example, between the first space 52 and the second space 72. The first exhaust valve 60 is, for example, a check valve that regulates the flow of air from another space to the first space 52 and the flow of air from the second space 72 to another space. As shown in FIG. 3 , the first exhaust valve 60 has a first surface 61 facing the first space 52 and a second surface 62 facing the second space 72. In this embodiment, the first exhaust valve 60 is, for example, a rapid exhaust valve. In the first embodiment, the pressure-receiving area S1 of the first surface 61 relative to the first space 52 is substantially the same as the pressure-receiving area S1 relative to the second space 72.

[0032] In the first embodiment, the first exhaust valve 60 changes its open / closed state in response to, for example, the air pressure difference (differential pressure) between the first space 52 and the second space 72. The first exhaust valve 60 changes its position in response to the differential pressure between the first space 52 and the second space 72, or the shape, such as the size of its opening, changes, thereby changing between an open state 60o and a closed state 60c.

[0033] For example, the first exhaust valve 60 is closed when the air pressure in the second space 72 is equal to or higher than the air pressure in the first space 52. In this case, the first space 52 is closed off from the other spaces, and the air in the first space 52 is discharged from the outlet 59 to the cuff 2.

[0034] On the other hand, for example, the first exhaust valve 60 is in an open state when the air pressure in the second space 72 is lower than the air pressure in the first space 52. In this case, the air in the first space 52 is discharged to the other spaces through the first exhaust valve 60, causing the air pressure in the first space 52 to rapidly approach the air pressure in the other spaces. Accordingly, the air supplied from the first space 52 to the cuff 2 is also sucked into the first space 52, causing the air pressure in the cuff 2 to also rapidly drop.

[0035] As shown in FIG. 3 , the volume of the second space 72 is much smaller than the volume of the first space 52. In this case, for example, when the first pressurizing unit 30 pressurizes both the first space 52 and the second space 72 as shown in FIG. 4 , the air pressure in the second space 72 increases faster than the air pressure in the first space 52. In this case, the first exhaust valve 60 is closed, as shown in FIG. 4 . FIG. 4 is a cross-sectional view showing an example of the air intake state of the pressure regulating mechanism in the first embodiment. As shown in FIG. 4 , in the air intake state, the pressing units 23 and 24 move up and down in the directions indicated by the arrows, thereby supplying air from the first pressurizing units 20 and 30 to the first space 52 as shown by arrows A1 and A3. Similarly, air is supplied from the first pressurizing unit 30 to the second space 72 as shown by arrow A2.

[0036] In this case, the amount of air supplied to the second space 72, indicated by arrow A2, is greater than the amount of air leaking from the air leak valve 79, indicated by arrow L1. Furthermore, the volume of the second space 72 is extremely small compared to the volume of the first space 52. Therefore, when the first pressurizing unit 30 starts pressurizing, the air pressure P2 in the second space 72 rises more rapidly than the increase in the air pressure P1 in the first space 52. As a result, the air pressure P2 in the second space 72 becomes higher than the air pressure P1 in the first space 52. This creates a pressure difference between the first space 52 and the second space 72, causing the first exhaust valve 60 to close.

[0037] On the other hand, when pressurization by the first pressurizer 30 is stopped, the supply of air to the second space 72, as indicated by arrow A2, is stopped. In this case, the first exhaust valve 60 is opened, as shown in FIG. 5 , resulting in an exhaust state. FIG. 5 is a cross-sectional view showing an example of the exhaust state of the pressure regulating mechanism in the first embodiment. As shown in FIG. 5 , air continues to leak from the second space 72 through the air leak valve 79, as indicated by arrow L1′, while the air pressure P1′ in the first space 52 remains high until the first exhaust valve 60 is opened. Because the volume of the second space 72 is small, the air pressure in the second space 72 drops rapidly due to the leaking air, as indicated by arrow L1′.

[0038] As a result, the air pressure in the second space 72 becomes lower than the air pressure in the first space 52. This opens the first exhaust valve 60, which was previously closed, and the first space 52 enters an exhaust state. In this case, the opening of the first exhaust valve 60 forms a gap G, and the air in the first space 52 is exhausted from the gap G to other spaces due to the pressure difference. This makes it possible to rapidly reduce the air pressure in the first space 52 and the cuff 2. The gap G is an example of a communication port.

[0039] As described above, the measurement device 1 in the first embodiment has the first space 52 that pressurizes the pressurization target 2 and the second space 72 that is independent of the first space 52. The measurement device 1 also includes the first exhaust valve 60 that closes or opens the communication port G that connects the first space 52 to another space. The open / close state of the first exhaust valve 60 changes depending on the pressure difference between the first space 52 and the second space 72. In addition, in the first embodiment, the first space 52 is pressurized by the multiple first pressurizers 20 and 30, and the second space 72 is pressurized by the first pressurizer 30. With this configuration, a pressure difference between the first space 52 and the second space 72 can be generated with a simple structure without significantly changing the configuration of an existing pump. This simplifies the structure of a pressure-boosting measurement device.

[0040] Second Embodiment In the first embodiment, the first pressurizing unit 30 that pressurizes the first space 52 also supplies air to the second space 72. However, the embodiment is not limited to this. For example, the second space may be pressurized by a pressurizing unit different from the first pressurizing unit.

[0041] The measuring device 1A in the second embodiment has the same appearance as the measuring device 1 shown in Fig. 1 except that the pump unit 5 is replaced with a pump unit 5A, and therefore is not shown in the drawings. Fig. 6 is a cross-sectional view showing an example of a pump in the second embodiment. As shown in Fig. 6, the pump unit 5A in the second embodiment includes a drive mechanism 80, a swing mechanism 90, pressure adjustment mechanisms 13 and 14, and a pair of outlets 57 and 58. Hereinafter, when there is no need to distinguish between the pressure adjustment mechanisms 13 and 14, they may be referred to as pressure adjustment mechanism 10A.

[0042] Fig. 7 is a cross-sectional view showing an example of a pressure regulating mechanism according to the second embodiment. As shown in Fig. 7, a pressure regulating mechanism 10A according to the second embodiment includes two first pressurizing units 20a and 20b, a second pressurizing unit 40, a first space 52, a first exhaust valve 60, and a pressure regulating unit 70A. Similar to the first pressurizing units 20 and 30 according to the first embodiment, the first pressurizing units 20a and 20b according to the second embodiment are disposed in opposing positions in the direction in which the oscillator 92 extends, with the shaft 91 shown in Fig. 6 interposed therebetween. Since the first pressurizing units 20a and 20b both have the same configuration as the first pressurizing unit 20 according to the first embodiment, detailed description thereof will be omitted.

[0043] The second pressurizing unit 40 does not supply air to the first space 52, but supplies air to the second space 72A of the pressure adjusting unit 70A shown in Fig. 7. The second pressurizing unit 40 includes a movable unit 41, a sealed space 42, pressing units 43 and 44, an intake port 45, an intake valve 46, and a fourth exhaust valve 48.

[0044] Similar to the movable part 21 and sealed space 22 of the first pressurizing part, the movable part 41 and sealed space 42 of the second pressurizing part 40 repeatedly take in and exhaust air in response to the up and down movement of the pressing parts 43 and 44. The second pressurizing part 40 supplies air supplied from the intake port 45 via the intake valve 46 to the second space 72A via the fourth exhaust valve 48. Note that the intake valve 46 is also a check valve similar to the intake valve 26, for example.

[0045] Furthermore, the fourth exhaust valve 48 is provided between the sealed space 42 and the second space 72A. The fourth exhaust valve 48 is also, for example, a check valve, and allows air to flow from the sealed space 22 to the second space 72 while restricting air from the second space 72 to the sealed space 22. This allows the second pressurizing unit 40 to supply air to the second space 72A without supplying air to the first space 52.

[0046] The pressure adjustment unit 70A shown in Figure 7 includes a second space 72A and an air leak valve 79A. The second space 72A is a space independent of the first space 52. The second space 72A is not sealed, and air constantly leaks into the other spaces via the air leak valve 79A. The structure of the pressure adjustment unit 70A is the same as that of the pressure adjustment unit 70 in the first embodiment, except that it is connected to the second pressurizing unit 40 instead of the first pressurizing unit 30, and therefore detailed description thereof will be omitted.

[0047] The second pressurizing unit 40 in the second embodiment may have a configuration similar to that of the first pressurizing unit 20. However, in consideration of the ratio of the volumes of the second space 72A and the first space 52, the second pressurizing unit 40 may have, for example, a smaller sealed space capacity or a smaller movable wall displacement than the first pressurizing unit 20, or may have fewer second pressurizing units than the first pressurizing unit 20. For example, in the second embodiment, as shown in FIGS. 6 and 7 , the pump unit 5A is provided with two second pressurizing units 40 for four first pressurizing units 20. Note that in the example shown in FIG. 7 , the second pressurizing unit 40 and the pressure adjusting unit 70A are disposed between the two first pressurizing units 20a and 20b in the direction in which the oscillator 92 extends, but the positions at which the second pressurizing unit 40 and the pressure adjusting unit 70A are disposed are not limited thereto.

[0048] The first exhaust valve 60A in the second embodiment is provided between the first space 52 and the second space 72A. Similar to the first exhaust valve 60, the first exhaust valve 60A also changes its open / closed state in accordance with, for example, the air pressure difference (differential pressure) between the first space 52 and the second space 72.

[0049] The intake state and exhaust state in the second embodiment will be described with reference to FIGS. 8 and 9. FIG. 8 is a cross-sectional view showing an example of the intake state of the pressure regulating mechanism in the second embodiment. As shown in FIG. 8, in the intake state, the amount of air A4 supplied from the second pressurizing section 40 to the second space 72A is greater than the amount of air L2 leaking from the air leak valve 79. In this case, when the second pressurizing section 40 starts pressurizing, the air pressure P4 in the second space 72 rises more rapidly than the increase in air pressure P3 in the first space 52. As a result, a pressure difference is generated between the first space 52 and the second space 72A, causing the first exhaust valve 60A to close.

[0050] On the other hand, when pressurization by the second pressurizer 40 is stopped, the supply of air to the second space 72A is stopped. FIG. 9 is a cross-sectional view showing an example of the exhaust state of the pressure regulating mechanism in the second embodiment. As shown in FIG. 9 , air continues to leak from the second space 72A through the air leak valve 79A as indicated by arrow L2′, while the air pressure P3′ in the first space 52 remains high until the first exhaust valve 60A is opened. As a result, the air pressure in the second space 72A becomes lower than the air pressure in the first space 52. As a result, the closed first exhaust valve 60 is opened, forming a gap G, and the air in the first space 52 is exhausted from the gap G to other spaces due to the pressure difference.

[0051] As described above, the measurement device 1A in the second embodiment includes the first pressurizing units 20a and 20b that pressurize the first space 52, and the second pressurizing unit 40 that pressurizes the second space 72. With this configuration, the second pressurizing unit 40 that pressurizes only the second space 72A can easily generate a pressure difference between the first space 52 and the second space 72A.

[0052] [Modifications] While the configurations of the respective embodiments have been described above, the embodiments are not limited thereto. For example, a plurality of second spaces 72 may be provided for one first space 52, or a plurality of pressurizing units may be provided to pressurize the second spaces 72. For example, two or more first pressurizing units 30 or second pressurizing units 40 may be provided, or a configuration may be provided that includes both the first pressurizing unit 30 and the second pressurizing unit 40.

[0053] Furthermore, although the configuration in which the air leak valve 79 is provided in the pressure adjustment section has been described, the configuration is not limited to this as long as it allows air in the second space 72 to constantly leak into other spaces. For example, the surface of the second space 72 may be roughened or grooved, or fine holes may be provided in the second space 72. Furthermore, the configuration may also be such that air leaks from the second exhaust valve 38 or the fourth exhaust valve 48.

[0054] Furthermore, for example, the flow path load from the first pressurizing unit 20 or 30 to the first space 52 may be greater than the flow path load from the first pressurizing unit 30 to the second space 72 or the flow path load from the second pressurizing unit 40 to the second space 72A. This allows a pressure difference between the first space and the second space to be generated even when there is no volumetric difference between the first space and the second space. To change the flow path load, for example, the hardness of the third exhaust valve 27 and the second exhaust valve 38 or the fourth exhaust valve 48 may be changed, or the length or width of the flow path to the first space 52 and the flow path to the second space 72 may be changed. Furthermore, a pressure difference can be generated more easily by combining a difference in flow path load with a difference in volume.

[0055] Furthermore, the first exhaust valve may be configured to be in an open state even when the pressure difference is small or when no pressure difference is occurring. For example, in the first embodiment, the pressure-receiving area of ​​the first surface 61 where the first exhaust valve 60 faces the first space 52 may be different from the pressure-receiving area of ​​the second surface 62 where the first exhaust valve 60 faces the second space 72. Fig. 10 is an enlarged cross-sectional view showing an example of the positional relationship between the first exhaust valve and the opening in the first modified example. Note that, although the following description will be based on the configuration of the first embodiment, each modified example can also be applied to the first exhaust valve 60A, the first space 52, and the second space 72A in the second embodiment.

[0056] As shown in Fig. 10 , the first surface 61 of the first exhaust valve 60 faces the first space 52 via an opening 65. The second surface 62 of the first exhaust valve 60 faces the second space 72B via an opening 67. In the first modified example, the area S2 of the opening 67, i.e., the pressure-receiving area of ​​the second surface 62 for the second space 72B, is smaller than the area S1 of the opening 65, i.e., the pressure-receiving area of ​​the first surface 61 for the first space 52. Note that Fig. 10 shows a state in which neither pressurization nor depressurization is performed on the first space 52 and the second space 72B. In this state, the air pressure P0 in the first space 52 and the second space 72B is substantially the same as the air pressure in the other spaces.

[0057] The operation of this configuration during pressurization and depressurization will be described with reference to Figures 11 to 13. Figure 11 is an enlarged cross-sectional view showing an example of the operation of the first exhaust valve in the intake state in the first modified example. As shown in Figure 11, when the air pressure P20 in the second space 72B becomes sufficiently higher than the air pressure P0 in the first space 52, the first exhaust valve 60 is closed. Then, as the first space 52 is closed by the first exhaust valve 60c in the closed state, air is supplied from the first pressurizers 20 and 30 to the first space 52, and the air pressure in the first space 52 also increases.

[0058] 12 is an enlarged cross-sectional view showing another example of the operation of the first exhaust valve in the intake state in the first modified example. As shown in Fig. 12, even when the air pressure in the first space 52 rises from P0 to P1, if the air pressure P2 in the second space 72B is sufficiently higher than the air pressure P1, the first exhaust valve 60 remains closed.

[0059] Next, when the air supply from the first pressurizing units 20 and 30 is stopped, the air pressure in the second space 72B suddenly drops due to air leakage from the air leak valve 79 shown in FIG. 3 . Meanwhile, the air pressure P1 in the first space 52 does not immediately drop even when the air supply is stopped because the first exhaust valve 60 is closed. As a result, as shown in FIG. 13 , the first exhaust valve 60 transitions to an open state depending on the difference between the air pressure P1 in the first space 52 and the air pressure P21 in the second space 72B. As a result, the air in the first space 52 is exhausted to the other spaces. FIG. 13 is an enlarged cross-sectional view showing an example of the operation of the first exhaust valve in the exhaust state in the first modified example. In FIG. 13 , the air pressure P21 in the second space 72B is substantially the same as the air pressure P1 in the first space 52. That is, compared to the exhaust state shown in FIG. 5 , FIG. 13 illustrates a state before the air pressure in the second space 72B has sufficiently dropped.

[0060] In the first modified example, the pressure-receiving area S1 of the first exhaust valve 60 relative to the first space 52 is larger than the pressure-receiving area S2 relative to the second space 72B, and therefore the first exhaust valve 60 transitions to the open state before the air pressure P21 in the second space 72B becomes lower than the air pressure P1 in the first space 52. With this configuration, the first space 52 can be transitioned to the exhaust state more quickly.

[0061] The pressure-receiving areas S1 and S2 of the first exhaust valve 60 may be set so that the first exhaust valve 60 can transition to the open state even when the air pressure in the second space is higher than the air pressure P1 in the first space. In this configuration, the transition to the exhaust state can be made even faster than in the first modification, and the first exhaust valve 60 can continue to remain in a stable exhaust state without returning to the closed state even when the air pressure in the second space decreases slowly in the exhaust state.

[0062] FIG. 14 is an enlarged cross-sectional view showing another example of the operation of the first exhaust valve in the exhaust state in the second modified example. As shown in FIG. 14, the pressure-receiving area S22 in the second modified example is even smaller than the pressure-receiving area S2 in the first modified example. FIG. 14 shows a state in which exhaust from the first space 52 progresses and the air pressure drops from P1 to P11. Furthermore, in the second modified example, the drop in air pressure in the first space 52 progresses more rapidly than the drop in air pressure in the second space 72C. In this case, as shown in FIG. 14, the air pressure P11 in the first space 52 may become lower than the air pressure P22 in the second space 72C.

[0063] Even in this state, in the second modified example, the difference between the pressure-receiving area S1 for the first space 52 and the pressure-receiving area S22 for the second space 72C prevents the first exhaust valve 60 from transitioning to the open state or vibrating between the open state and the closed state, thereby maintaining a stable exhaust state.

[0064] In each of the modified examples, the pressure difference between the first space 52 and the second space required for the first exhaust valve 60 to transition from the open state to the closed state is larger than in each of the embodiments. However, in each of the modified examples, the volumes of the second spaces 72B and 72C are also sufficiently smaller than the volume of the first space 52, so the effect on the time lag when pressurizing the second space is small.

[0065] While the present invention has been described above based on the embodiments and modifications, it goes without saying that the present invention is not limited to the embodiments and modifications, and various modifications are possible without departing from the spirit of the present invention. Such modifications without departing from the spirit of the present invention are also included in the technical scope of the present invention, and this will be clear to those skilled in the art from the description of the claims.

[0066] REFERENCE SIGNS LIST 1, 1A Measuring device (sphygmomanometer), 2 Cuff, 3 Main body, 4 Tube, 5, 5A Pump unit, 6 Control unit, 10, 10A (11-14) Pressure regulating mechanism, 20, 20a, 20b, 30 First pressurizing unit, 21, 41 Movable unit, 22, 42 Sealed space, 23, 24, 43, 44 Pressurizing unit, 25, 45 Intake port, 26, 46 Intake valve, 27 Third exhaust valve, 38 Second exhaust valve, 40 Second pressurizing unit, 48 Fourth exhaust valve, 52 First space, 57, 58, 59 Outlet port, 60, 60A First exhaust valve, 70, 70A Pressure regulating unit, 72, 72A, 72B, 72C Second space, 79, 79A Air leak valve, 80 Drive mechanism, 81, 82 Actuator, 90 Oscillating mechanism, 91 Shaft, 92 Oscillator

Claims

1. A first space for pressurizing a pressurized object; A second space independent of the first space; having a first exhaust valve that closes or opens a communication port that communicates the first space with another space, The opening / closing state of the first exhaust valve changes according to a pressure difference between the first space and the second space. Measuring equipment.

2. The first exhaust valve is When the pressure in the first space is lower than the pressure in the second space, the first space is closed and pressurizes the pressurized object; When the pressure in the first space is equal to or higher than the pressure in the second space, the pressure in the first space is lowered by releasing the pressure in the first space.

2. The measuring device of claim 1.

3. The measuring device according to claim 1 or 2, wherein the volume of the first space is larger than the volume of the second space.

4. The measuring device according to claim 1 , further comprising a first pressurizing unit that pressurizes the first space and the second space.

5. The first space is pressurized by a plurality of the first pressurizing portions, The second space is pressurized by at least one of the first pressurizing units.

5. The measuring device according to claim 4.

6. A second exhaust valve provided between at least any one of the first pressurizing parts and the second space; an air leak valve communicating the second space with another space; Further comprising:

6. The measuring device according to claim 4 or 5.

7. A measuring device described in any one of claims 4 to 6, wherein the flow path load from the first pressure section to the first space is greater than the flow path load from the first pressure section to the second space.

8. A first pressurizing unit that pressurizes the first space; Further comprising a second pressurizing unit that pressurizes the second space.

4. A measuring device according to claim 1.

9. A measuring device as described in claim 8, wherein the flow path load from the first pressure section to the first space is greater than the flow path load from the second pressure section to the second space.

10. A fourth exhaust valve provided between the second pressurizing section and the second space; an air leak valve communicating the second space with another space; Further comprising:

10. The measuring device according to claim 8 or 9.

11. the first exhaust valve has a first surface facing the first space and a second surface facing the second space, The pressure-receiving area of ​​the first surface is larger than the pressure-receiving area of ​​the second surface.

11. Measuring device according to any one of the preceding claims.