WO2020162086A1

WO2020162086A1 - Medical device

Info

Publication number: WO2020162086A1
Application number: PCT/JP2020/000178
Authority: WO
Inventors: 靖志田中; 山本　円朗
Original assignee: リバーフィールド株式会社
Priority date: 2019-02-07
Filing date: 2020-01-07
Publication date: 2020-08-13
Also published as: JP2020128762A

Abstract

This medical device is characterized by being provided with: a gas pressure actuator; a first flow path; a second flow path; a first closing valve provided to the first flow path; a second closing valve provided to the second flow path; a first exhaust valve that controls the exhaust of a gas to the outside of the first flow path, and the shutoff of such exhaust; a second exhaust valve that controls the exhaust of the gas to the outside of the second flow path, and the shutoff of such exhaust; and a throttle valve capable of changing the flow path cross-sectional area of the gas released from the first exhaust valve and the second exhaust valve.

Description

Medical equipment

Cross-reference of related applications

This international application claims priority based on Japanese Patent Application No. 2019-020732 filed with the Japan Patent Office on February 7, 2019, and is based on Japanese Patent Application No. 2019-020732. The entire contents of this International Application are incorporated by reference.

The present disclosure relates to a medical device whose movement is controlled by an actuator driven by gas pressure.

In recent years, surgery supported by medical devices such as medical robots is becoming widespread. For example, the medical devices described in Patent Documents 1 and 2 are provided with various actuators that control movement.

Patent Document 1 discloses a vibrating body that generates a vibrating wave, a moving body that is arranged to face the vibrating body and that moves by receiving the vibrating wave, and a pressure unit that controls the contact pressure of the vibrating body and the moving body. A structured actuator is disclosed. The actuator described in Patent Document 1 controls the contact pressure of the vibrating body and the moving body to control the driving force generated by the combination of the vibrating body and the moving body.

Patent Document 2 discloses a configuration including an air/water feeding device, an air/water feeding channel, and a normally open solenoid valve. In the configuration described in Patent Document 2, the pressure in the air/water feeding channel can be increased by closing the electromagnetic valve and supplying air to the air/water feeding channel. Thereby, for example, the curved shape of the air supply/water supply channel can be deformed straight.

JP, 2014-003734, A JP, 2010-035587, A

On the other hand, in the case of medical equipment used for surgery support, it is required that an emergency stop can be made to stop the operation of the medical equipment for some reason. As a method for realizing an emergency stop, a method using a brake using an electromagnet is generally known. In the following, a brake that uses an electromagnet will also be referred to as an electromagnetic brake.

In other words, by placing an electromagnetic brake on the movable part of the medical device and controlling the power supply to the electromagnetic brake, the movement of the movable part is regulated and the emergency stop of the medical device is realized.

However, when arranging the electromagnetic brake on the medical device, heavy parts such as an electromagnet and a brake pad are arranged, which causes a problem that the weight of the medical device becomes heavy.

Also, there was a problem that the size of the medical device would increase because a new electromagnetic brake would be placed on the medical device. In the case of a medical device used for surgery support, there is a restriction on the size of the space in which the medical device can be placed, so that it becomes a problem that the medical device cannot be placed if the size of the medical device becomes large.

Further, since the electromagnetic brake is newly arranged in the medical device, the cost of the electromagnetic brake is increased as compared with the medical device in which the electromagnetic brake is not arranged, and the cost of the medical device increases. there were.

A gas pressure actuator driven by the pressure of gas such as air is known as an actuator used for medical equipment. By combining the gas pressure actuator and the electromagnetic brake, it is possible to perform an emergency stop for stopping the operation of the medical device.

However, when the medical device is stopped by the electromagnetic brake in an emergency, the pressure difference of the gas pressure at the time of the emergency stop may remain inside the gas pressure actuator. At this time, if the electromagnetic brake is released, there is also a problem that the gas pressure actuator may perform an unintended operation based on the remaining pressure difference.

The present disclosure has been made in order to solve the above-described problems, and promptly performs an operation related to an emergency stop in a medical device using a gas pressure actuator, and suppresses an unintended operation, and as a medical device. An object of the present invention is to provide a medical device that can be used easily.

In order to achieve the above object, the present disclosure provides the following means.

The medical device of the present disclosure has a cylinder formed in a tubular shape, and a piston that is arranged so as to be relatively movable in the axial direction of the cylinder and that partitions the internal space of the cylinder into a first space and a second space. Inflow and outflow of gas between the first space and a first flow path connected to allow inflow and outflow of gas between the gas pressure actuator and the first space A second flow path connected to the first flow path; a first closing valve provided in the first flow path to control the flow and cutoff of the gas supplied from the outside to the first space; Second shut-off valve provided in the flow passage of No. 1 for controlling the flow and shut-off of the gas supplied from the outside to the second space, the cylinder and the first shut-off valve in the first flow passage. Between the first exhaust valve that controls exhaust and shutoff of the gas to the outside of the first flow path, and between the cylinder and the second closing valve in the second flow path. A second exhaust valve for controlling exhaust and shutoff of the gas to the outside of the second flow path, and a flow path cross-sectional area of the gas exhausted from the first exhaust valve and the second exhaust valve And a throttling valve that can change.

According to the medical device of the present disclosure, it is possible to stop the relative movement of the piston with respect to the cylinder by cutting off the supply of gas to the cylinder with the first closing valve and the second closing valve. In other words, the gas pressure actuator can be stopped urgently.

Further, after the gas pressure actuator is stopped, the pressure of the first space and the second space of the cylinder is reduced to the atmospheric pressure by allowing the gas to be discharged from the first exhaust valve and the second exhaust valve. , The pressure difference between the two is eliminated. Thereby, the unintended operation of the gas pressure actuator can be suppressed.

The pressure drop in the first space and the second space is controlled by the flow passage cross-sectional area by the throttle valve. That is, as the flow passage cross-sectional area of the throttle valve increases, the gas exhaust rate increases and the pressure decreases in a short period of time. On the other hand, when the flow passage cross-sectional area of the throttle valve becomes small, the gas exhaust rate becomes small, and it takes a long time to reduce the pressure.

In addition, as compared with the case where an electromagnetic brake is used for emergency stop of medical equipment, compared with electromagnets and brake pads called first and second closing valves, first and second exhaust valves, and a throttle valve. Since lightweight, small, and inexpensive parts are used, it is easy to suppress weight increase, size increase, and price increase.

In the above disclosure, the first shutoff valve and the second shutoff valve are integrally formed shutoff valves, and the gases exhausted from the first exhaust valve and the second exhaust valve are the same. Of the gas flowing toward the throttle valve between the first exhaust valve and the throttle valve and between the second exhaust valve and the throttle valve. It is preferable that a non-return valve permitting is provided.

Thus, by forming the first closing valve and the second closing valve integrally, it becomes possible to reduce the number of parts constituting the medical device as compared with the case where they are provided separately. .. Further, since one throttle valve is arranged for the first exhaust valve and the second exhaust valve, the size and weight of the medical device can be reduced as compared with the case where two throttle valves are arranged. Easy to plan.

Further, by arranging the check valves between the first exhaust valve and the throttle valve and between the second exhaust valve and the throttle valve, respectively, from the first space to the second space, or Backflow of gas from the second space to the first space can be suppressed.

In the above disclosure, the first closing valve and the first exhaust valve are a first valve device integrally formed, and the second closing valve and the second exhaust valve are integrally formed. A second valve device, the gas exhausted from the first exhaust valve is guided to a first throttle valve, and the gas exhausted from the second exhaust valve is a second throttle valve. It is preferably led to a valve.

Thus, the first valve device in which the first closing valve and the first exhaust valve are integrally formed, and the second valve device in which the second closing valve and the second exhaust valve are integrally formed are provided. As a result, it is possible to reduce the number of parts constituting the medical device as compared with the case where the first blocking valve, the first exhaust valve, the second blocking valve and the second exhaust valve are separately arranged. Become.

By arranging the first throttle valve with respect to the first exhaust valve and the second throttle valve with respect to the second exhaust valve, the first throttle valve is compared with the case where a common throttle valve is provided. It is possible to independently control the rate of pressure decrease in the space and the second space.

In the above disclosure, the first closing valve and the second closing valve are integrally formed closing valves, and the gas exhausted from the first exhaust valve is guided to the first throttle valve. The gas exhausted from the second exhaust valve is preferably guided to the second throttle valve.

As described above, by forming the first closing valve and the second closing valve as the integrally formed closing valve, it is possible to reduce the number of parts constituting the medical device as compared with the case where they are provided separately. Become.

According to the medical device of the present disclosure, an emergency stop can be promptly performed by shutting off the supply of gas to the cylinder by the first closing valve and the second closing valve. Further, by permitting the discharge of gas from the first exhaust valve and the second exhaust valve after the gas pressure actuator is stopped, it is possible to quickly perform an operation related to an emergency stop and suppress an unintended operation. .. Further, according to the present disclosure, there is an effect that safety can be improved when used as a medical device.

It is a schematic diagram explaining the structure of the shaft, joint part, and forceps which concern on the medical device of 1st Embodiment of this indication. 1 is a schematic diagram illustrating a circuit configuration of a medical device according to a first embodiment of the present disclosure. FIG. 3 is a cross-sectional view illustrating a configuration of a joint section of FIG. 1. FIG. 3 is a schematic diagram illustrating a circuit configuration of a characteristic part in the drive unit of FIG. FIG. 3 is a block diagram illustrating a configuration of a control unit in FIG. 2. FIG. 6A is a schematic diagram illustrating a state in which an external force is applied to the pneumatic actuator during an emergency stop, and FIG. 6B is a schematic diagram illustrating a state in which the external force is removed. It is a graph explaining a pressure change when an exhaust valve is opened after an emergency stop. It is a schematic diagram explaining the structure of the drive part which concerns on the medical device of the 2nd Embodiment of this embodiment. It is a graph explaining a pressure change when an exhaust valve is opened after an emergency stop. It is a schematic diagram explaining the structure of the drive part which concerns on the medical device of the 3rd Embodiment of this embodiment.

1, 101, 201... Medical equipment, 23... Open/close solenoid valve (first closing valve, second closing valve), 26a... First exhaust valve, 26b... Second exhaust valve, 28... Variable throttle (throttle) Valve), 30...pneumatic actuator (gas pressure actuator), 31...cylinder, 32...piston, 33a...first space, 33b...second space, 121a...first valve device, 121b...second valve device , 123a...first opening/closing solenoid valve (first closing valve), 123b...second opening/closing solenoid valve (second closing valve), 128a, 228a...first variable throttle (throttle valve), 128b, 228b …Second variable throttle (throttle valve)

[First Embodiment]
Hereinafter, the medical device 1 according to the first embodiment of the present disclosure will be described with reference to FIGS. 1 to 7. In the present embodiment, the medical device 1 will be described as being applied to an example in which the medical device 1 is a medical robot used for assistance in endoscopic surgery. Specifically, as shown in FIG. 1, the medical device 1 is a device in which forceps 52 are arranged at the tip of a shaft 51 formed in a rod shape. A joint portion 53 is provided near the tip of the shaft 51. By bending the joint portion 53, the direction of the forceps 52 can be operated.

As shown in FIG. 2, the medical device 1 includes a compressor 11, a main valve 12, a first drive unit 20A, a second drive unit 20B, a third drive unit 20C, a fourth drive unit 20D, and a control unit 40. And are mainly provided. The compressor 11, the main valve 12, the first drive unit 20A, the second drive unit 20B, the third drive unit 20C, and the fourth drive unit 20D are used to drive the joint unit 53.

The compressor 11 is a device that supplies the first drive unit 20A, the second drive unit 20B, the third drive unit 20C, and the fourth drive unit 20D with air pressurized to a predetermined pressure. A known structure can be used for the method and mechanism for increasing the pressure of air, and is not particularly limited. Further, a device that supplies air of a predetermined pressure by a cylinder storing high-pressure air instead of the compressor 11 may be used. The gas used to drive the first drive unit 20A, the second drive unit 20B, the third drive unit 20C, and the fourth drive unit 20D may be air or another gas.

The main valve 12 is a valve that controls the supply of air from the compressor 11 to the first drive unit 20A, the second drive unit 20B, the third drive unit 20C, and the fourth drive unit 20D. In the present embodiment, description will be made by applying to an example of the main valve 12 that controls the supply of air based on a control signal input from the control unit 40. In the present embodiment, a source pressure sensor 13 that measures the pressure of air after passing through the source valve 12 is arranged. The form of the main valve 12 may be a known form and is not particularly limited.

The first drive unit 20A, the second drive unit 20B, the third drive unit 20C, and the fourth drive unit 20D are connected in parallel to the compressor 11. The first drive unit 20A, the second drive unit 20B, the third drive unit 20C, and the fourth drive unit 20D are supplied with the branched air after passing through the main valve 12.

The first drive unit 20A is configured to generate a force that pulls the position A at 0° in FIG. 3 when the joint 53 is viewed from the forceps 52 side. Here, pulling means pulling toward the base side of the shaft 51 on which the first drive unit 20A is arranged, that is, the side opposite to the forceps 52. For example, a wire that connects the first drive unit 20A and the position A of the joint unit 53 is provided, and the position A is pulled by the first drive unit 20A via the wire.

Similarly, the second drive unit 20B is configured to generate a force that pulls the position B at 90°. The third drive unit 20C is configured to generate a force that pulls the position C of 180°. The fourth drive unit 20D generates a force that pulls the position D of 270°. Note that the description of 0°, 90°, 180°, and 270° in the above description is used to describe the relative relationship between the respective positions, and does not mean an absolute angle.

The joint portion 53 shown in FIG. 1 has a structure that can be bent in any direction. Therefore, the joint 53 can be bent in a desired direction by combining the forces generated in the first drive unit 20A, the second drive unit 20B, the third drive unit 20C, and the fourth drive unit 20D.

Since the configurations of the first drive unit 20A, the second drive unit 20B, the third drive unit 20C, and the fourth drive unit 20D are all the same, they will be described without distinguishing between them. When the first drive unit 20A, the second drive unit 20B, the third drive unit 20C, and the fourth drive unit 20D are not distinguished, they are simply referred to as the drive unit 20.

As shown in FIGS. 2 and 4, the drive unit 20 includes a control servo valve 21, a first servo-side pressure sensor 22a and a second servo-side pressure sensor 22b, an opening/closing solenoid valve 23, and a pneumatic actuator. 30, the first opening/closing side pressure sensor 25a and the second opening/closing side pressure sensor 25b, the first exhaust valve 26a and the second exhaust valve 26b, the first check valve 27a and the second check valve. A valve 27b, a variable throttle 28 that is a throttle valve, and a silencer 29 are mainly provided.

The opening/closing solenoid valve 23 includes a first closing valve and a second closing valve. The pneumatic actuator 30 is also referred to as a pneumatic actuator when a gas other than air is used.

Further, is the control servo valve 21, the opening/closing solenoid valve 23, and the pneumatic actuator 30 provided in any of the first drive unit 20A, the second drive unit 20B, the third drive unit 20C, and the fourth drive unit 20D. In the case of distinguishing from each other, each code is described by adding A, B, C, and D. For example, in the case of the control servo valve 21, they are described as a control servo valve 21A, a control servo valve 21B, a control servo valve 21C, and a control servo valve 21D, respectively.

Similarly, the first servo side pressure sensor 22a and the second servo side pressure sensor 22b, the first exhaust valve 26a and the second exhaust valve 26b, the first check valve 27a and the second check valve 27b. , And the first open/close side pressure sensor 25a and the second open/close side pressure sensor 25b in any of the first drive unit 20A, the second drive unit 20B, the third drive unit 20C, and the fourth drive unit 20D. When distinguishing whether or not it is provided, it is described by adding A, B, C, and D to each code.

For example, in the case of the first servo side pressure sensor 22a and the second servo side pressure sensor 22b, the first servo side pressure sensor 22Aa, the second servo side pressure sensor 22Ab, and the first servo side pressure sensor, respectively. 22Ba and a second servo side pressure sensor 22Bb, a first servo side pressure sensor 22Ca and a second servo side pressure sensor 22Cb, and a first servo side pressure sensor 22Da and a second servo side pressure sensor 22Db. To do.

The control servo valve 21 is arranged between the main valve 12 and the opening/closing solenoid valve 23. Between the control servo valve 21 and the main valve 12, air is circulated by one pipe branching toward the first drive unit 20A, the second drive unit 20B, the third drive unit 20C, and the fourth drive unit 20D. Connected possible. Further, the control servo valve 21 and the opening/closing solenoid valve 23 are connected by a first flow path 23a and a second flow path 23b, which are two pipes arranged in parallel, so that air can flow therethrough. There is.

The control servo valve 21 is configured to guide the air passing through the main valve 12 to a first space 33a or a second space 33b of a pneumatic actuator 30 described later. The selection of the first space 33a and the second space 33b, which are the partners to guide the air, is performed based on the control signal input from the control unit 40. The configuration of the control servo valve 21 may be a known configuration and is not particularly limited.

The servo side pressure sensor 22a and the servo side pressure sensor 22b are sensors that measure the pressure of air between the control servo valve 21 and the opening/closing solenoid valve 23. In other words, the air introduced to the first space 33a or the second space 33b of the pneumatic actuator 30 by the servo side pressure sensor 22a and the servo side pressure sensor 22b, which is the air before passing through the opening/closing solenoid valve 23. The pressure is measured. The value of the measured air pressure is input to the control unit 40 as a sensor output. Known pressure sensors can be used as the servo side pressure sensor 22a and the servo side pressure sensor 22b.

The opening/closing solenoid valve 23 is arranged between the control servo valve 21 and the pneumatic actuator 30. Between the on-off solenoid valve 23 and the control servo valve 21, there are two pipes, a first flow path 23a and a second flow passage 23a corresponding to the first space 33a and the second space 33b of the pneumatic actuator 30, respectively. The flow path 23b is connected so that air can flow. The open/close solenoid valve 23 and the pneumatic actuator 30 are connected so that air can flow through the first flow path 23a and the second flow path 23b corresponding to the first space 33a and the second space 33b, respectively. ing.

The opening/closing solenoid valve 23 opens/closes and opens the first flow path 23a communicating from the control servo valve 21 to the first space 33a of the pneumatic actuator 30, and opens the first flow path 23a from the control servo valve 21 to the second space. It is a valve that controls opening and closing of the second flow path 23b communicating with 33b and opening to the outside.

In this embodiment, the control servo valve 21 and the first space 33a are closed, and the control servo valve 21 and the second space 33b are closed, and the control servo valve 21 and the first space 33b are closed. A state in which the spaces 33a are communicated with each other and the second space 33b is opened to the outside, and a state in which the first space 33a is opened to the outside and the control servo valve 21 and the second space 33b are connected to each other The description will be given by applying it to the case of controlling by three states of communicating. The open/close solenoid valve 23 may have any known structure and is not particularly limited. Further, a state in which the control servo valve 21 and the first space 33a are communicated with each other is also referred to as a state in which the control servo valve 21 and the first space 33a are opened, and the control servo valve 21 and the second space 33a The state in which the spaces 33b are communicated with each other is also referred to as a state in which the control servo valve 21 and the second space 33b are opened.

The pneumatic actuator 30 is configured to generate a driving force for bending the joint 53 using the pressure of air supplied from the compressor 11. The pneumatic actuator 30 is mainly provided with a cylinder 31 formed in a cylindrical shape and a piston 32 arranged so as to be movable relative to the cylinder 31.

The inside of the cylinder 31 is divided by a piston 32 into a first space 33a and a second space 33b. A first flow path 23a and a second flow path 23b, which communicate with the first space 33a and the second space 33b, are arranged between the cylinder 31 and the opening/closing solenoid valve 23, respectively. The piston 32 is provided with a transmission member (not shown) such as a wire for transmitting the relative movement with respect to the cylinder 31 to the joint portion 53.

The open/close side pressure sensor 25a and the open/close side pressure sensor 25b are sensors for measuring the pressure of air between the open/close solenoid valve 23 and the pneumatic actuator 30. In other words, the pressure of the air that has been introduced into the first space 33a or the second space 33b of the pneumatic actuator 30 after passing through the opening/closing solenoid valve 23 is the opening/closing side pressure sensor 25a and the opening/closing side pressure sensor 25b. Measured by The value of the measured air pressure is input to the control unit 40 as a sensor output. Known pressure sensors can be used as the opening/closing pressure sensor 25a and the opening/closing pressure sensor 25b.

The exhaust valve 26a and the exhaust valve 26b are arranged in the exhaust pipe 35 which is branched from the first flow passage 23a and the second flow passage 23b which are pipes between the opening/closing solenoid valve 23 and the pneumatic actuator 30, and which is opened to the outside. It is a valve that is used. The exhaust pipe 35 has a single end on the side open to the outside, and the second end on the side where the exhaust valve 26a and the exhaust valve 26b are arranged is branched into two pipes. It is a Y-shaped pipe.

The exhaust valve 26a and the exhaust valve 26b are valves that control communication and closing of the exhaust pipe 35 based on a control signal input from the control unit 40. In other words, the exhaust of the air inside the first space 33a or the second space 33b of the pneumatic actuator 30 is controlled by the exhaust valve 26a and the exhaust valve 26b.

The check valve 27a and the check valve 27b are valves arranged in the exhaust pipe 35 between the exhaust valve 26a and the exhaust valve 26b and the silencer 29, respectively. The check valve 27a is a valve that allows the flow of air from the exhaust valve 26a toward the silencer 29 and blocks the flow of air from the silencer 29 toward the exhaust valve 26a. The check valve 27b is a valve that allows the flow of air from the exhaust valve 26b toward the silencer 29 and blocks the flow of air from the silencer 29 toward the exhaust valve 26b. As the check valve 27a and the check valve 27b, valves having a known structure can be used.

The variable throttle 28 is arranged near the end of the exhaust pipe 35 on the side open to the outside and on the check valve 27a and check valve 27b sides of the silencer 29. The variable throttle 28 adjusts the flow rate per unit time when the air is discharged from the exhaust pipe 35 to the outside. A known configuration may be used as the variable diaphragm 28.

The silencer 29 is arranged at the end of the exhaust pipe 35 that is open to the outside. The silencer 29 is configured to reduce the sound generated when the air is discharged from the exhaust pipe 35 to the outside, or to suppress the generation of the sound. A known configuration may be used as the silencer 29.

The control unit 40 is configured to control at least the bending of the joint 53. The control unit 40 is a microcomputer having a central processing unit, which is a CPU, ROM, RAM, an input/output interface, and the like. The program stored in the storage device such as the ROM described above is a program that causes the CPU, the ROM, the RAM, and the input/output interface to cooperate with each other.

As shown in FIG. 5, the control unit 40 includes a control input for instructing bending of the joint portion, an original pressure sensor 13, a servo pressure sensor 22a and a servo pressure sensor 22b, and opening/closing. The signals output from the side pressure sensor 25a and the opening/closing side pressure sensor 25b are mainly input.

The control unit 40 also generates and generates a control signal for controlling the control servo valve 21, the opening/closing solenoid valve 23, the exhaust valve 26a, and the exhaust valve 26b based on the control input and the signals output from various sensors. The control signal is output.

Next, the operation of the medical device 1 having the above configuration will be described. First, the operation of bending the joint portion 53 will be described with reference to FIGS. 2 to 4. When the joint portion 53 is bent, as shown in FIG. 2, the control unit 40 outputs a control signal for controlling the main valve 12 so that air can be supplied from the compressor 11 to the drive unit 20.

Next, the control unit 40 controls the drive unit 20 corresponding to the direction in which the joint 53 is bent. For example, description will be given by applying to an example of controlling the first drive unit 20A. The control unit 40 controls the servo valve 21A for guiding air to the first space 33Aa or the second space 33Ab of the pneumatic actuator 30A. For example, a control signal for guiding air to the first space 33Aa is generated and output to the control servo valve 21A.

Further, the control unit 40 outputs a control signal to the opening/closing solenoid valve 23A shown in FIGS. 2 and 4, which enables air to flow into the first space 33Aa. The first space 33Aa into which the air pressurized by the compressor 11 flows has a higher pressure than the second space 33Ab.

The piston 32 of the pneumatic actuator 30 moves to the second space 33Ab side due to the pressure difference between the first space 33Aa and the second space 33Ab. As shown in FIG. 3, the movement of the piston 32 is transmitted to the position A in the joint 53 via the wire, and a force pulling the position A is generated. This causes the joint portion 53 to bend.

Next, the operation of the medical device 1 during an emergency stop will be described. At the time of emergency stop, as shown in FIG. 2, the control unit 40 closes the opening/closing solenoid valve 23 between the control servo valve 21 and the first space 33a, and controls the control servo valve 21 and the second space 33a. A control signal for closing the space 33b is output.

At this time, as shown in FIG. 6A, the pressure difference between the first space 33a and the second space 33b in the pneumatic actuator 30 causes the external force F applied to the piston 32 via the joint portion 53, and the piston 32 stops. Balance to do.

For example, when the external force F applied to the piston 32 via the joint portion 53 disappears from the state shown in FIG. 6A for some reason, the piston 32 reaches the position where the pressure difference between the first space 33a and the second space 33b becomes equal. Moving. As a result, the joint portion 53 bends unintentionally.

In order to suppress such unintended bending, the control unit 40 performs the control described below. The control unit 40 outputs a control signal for opening the exhaust valve 26a and the exhaust valve 26b. As shown in FIG. 4, the exhaust valve 26a to which the control signal is input makes the first space 33a of the pneumatic actuator 30 communicate with the exhaust pipe 35, and the exhaust valve 26b communicates with the second space 33b of the pneumatic actuator 30. It communicates with the exhaust pipe 35.

The air in the first space 33a passes through the check valve 27a, the variable throttle 28 and the silencer 29 and is discharged to the outside. The air in the second space 33b passes through the check valve 27b, the variable throttle 28 and the silencer 29 and is discharged to the outside.

Since the check valve 27a and the check valve 27b are provided, the air in the first space 33a flows into the second space 33b, and the air in the second space 33b goes to the first space 33a. Inflow is prevented.

The air pressure Pa in the first space 33a and the air pressure Pb in the second space 33b change as shown in FIG. First, when the exhaust valve 26a and the exhaust valve 26b are closed, the air pressure Pa is P1 and the air pressure Pb is P2. Here, P1>P2. When the

exhaust valves

26a and 26b are opened, the air pressure Pa, which is a relatively high pressure, begins to decrease. When the air pressure Pa decreases to P2, the air pressure Pa and the air pressure Pb similarly decrease. The decrease of the air pressure Pa and the air pressure Pb continues until it becomes equal to the external pressure, that is, the atmospheric pressure.

According to the medical device 1 having the above configuration, the relative movement of the piston 32 with respect to the cylinder 31 can be stopped by shutting off the supply of air to the cylinder 31 by the opening/closing solenoid valve 23. In other words, the pneumatic actuator 30 can be brought to an emergency stop.

Further, after the pneumatic actuator 30 is stopped, the pressure in the first space 33a and the second space 33b of the cylinder 31 is increased by allowing the air to be discharged from the first exhaust valve 26a and the second exhaust valve 26b. The pressure drops to atmospheric pressure and the pressure difference between the two is eliminated. Thereby, the unintended operation of the pneumatic actuator 30 can be suppressed.

The pressure drop in the first space 33a and the second space 33b is controlled by the flow passage cross-sectional area of the variable throttle 28. That is, when the flow passage cross-sectional area in the variable throttle 28 increases, the exhaust speed of air increases and the pressure decreases in a short period of time. On the other hand, when the flow passage cross-sectional area in the variable throttle 28 becomes small, the air exhaust velocity becomes small, and it takes a long time to reduce the pressure.

In addition, compared with the case where an electromagnetic brake is used for an emergency stop of the medical device 1, an opening/closing solenoid valve 23, a first exhaust valve 26a and a second exhaust valve 26b, and an electromagnet or a brake pad called a variable throttle 28 are provided. In comparison, since lightweight, small, and inexpensive parts are used, it is easy to suppress weight increase, size increase, and price increase.

By using the on-off solenoid valve 23 formed integrally, it is possible to reduce the number of parts constituting the medical device 1 as compared with the case where a plurality of on-off solenoid valves are provided. Further, since one variable throttle 28 is arranged for the first exhaust valve 26a and the second exhaust valve 26b, the medical device 1 can be made smaller as compared with the case where two throttle valves are respectively arranged. It is easy to reduce the weight.

Further, by arranging the check valve 27a and the check valve 27b between the first exhaust valve 26a and the variable throttle 28, and between the second exhaust valve 26b and the variable throttle 28, respectively, the first space The backflow of air from 33a to the second space 33b or from the second space 33b to the first space 33a can be suppressed.

[Second Embodiment]
Next, a second embodiment of the present disclosure will be described with reference to FIGS. 8 and 9. The basic configuration of the medical device of this embodiment is the same as that of the first embodiment, but the configuration of the drive unit is different from that of the first embodiment. Therefore, in the present embodiment, the configuration of the drive unit will be described with reference to FIGS. 8 and 9, and description of other configurations will be omitted.

As shown in FIG. 8, the drive unit 120 of the medical device 101 according to the present embodiment includes a first valve device 121a and a second valve device 121b, a first opening/closing side pressure sensor 25a, and a second opening/closing side. A pressure sensor 25b, a throttle valve 128a that is a first variable throttle, a throttle valve 128b that is a second variable throttle, a first silencer 129a, and a second silencer 129b are mainly provided.

The first valve device 121a is a device arranged in a first space 33a which is a space between the control servo valve 21 and the pneumatic actuator 30. The second valve device 121b is a device arranged in the second space 33b which is a space between the control servo valve 21 and the pneumatic actuator 30.

The first valve device 121a is mainly provided with a first closing valve 123a, which is a first opening/closing solenoid valve, and a first exhaust valve 26a. The second valve device 121b is mainly provided with a second closing valve 123b, which is a second opening/closing solenoid valve, and a second exhaust valve 26b.

The first opening/closing solenoid valve 123a is a valve that controls opening/closing of the first flow path 23a that communicates with the control servo valve 21 to the first space 33a of the pneumatic actuator 30. The second opening/closing solenoid valve 23b is a valve that controls opening/closing of the second flow path 23b that communicates with the control servo valve 21 to the second space 33b of the pneumatic actuator 30.

The first exhaust valve 26a is a valve that is arranged in the exhaust pipe 135a that is branched from the first flow path 23a between the opening/closing solenoid valve 23 and the first space 33a of the pneumatic actuator 30 and is open to the outside. The second exhaust valve 26b is a valve disposed in an exhaust pipe 135b that is branched from the second flow path 23b between the opening/closing solenoid valve 23 and the second space 33b of the pneumatic actuator 30 and is open to the outside.

The first exhaust valve 26a is a valve that controls communication and closing of the exhaust pipe 135a based on a control signal input from the control unit 40. In other words, the exhaust of the air inside the first space 33a of the pneumatic actuator 30 is controlled by the first exhaust valve 26a.

The second exhaust valve 26b is a valve that controls communication and closing of the exhaust pipe 135b based on a control signal input from the control unit 40. In other words, the exhaust of the air inside the second space 33b of the pneumatic actuator 30 is controlled by the second exhaust valve 26b.

The first variable throttle 128a is arranged in the first exhaust pipe 135a. The second variable throttle 128b is arranged in the second exhaust pipe 135b. More specifically, the first variable throttle 128a is arranged between the first valve device 121a and the first silencer 129a in the first exhaust pipe 135a, and the second variable throttle 128b is the second variable throttle 128b. It is disposed between the second valve device 121b and the second silencer 129b in the exhaust pipe 135b.

The first variable throttle 128a is configured to adjust the flow rate per unit time when air is discharged from the first exhaust pipe 135a to the outside. The second variable throttle 128b is configured to adjust the flow rate per unit time when air is discharged from the second exhaust pipe 135b to the outside. Known configurations may be used as the first variable aperture 128a and the second variable aperture 128b.

The first silencer 129a is arranged at the end of the first exhaust pipe 135a on the side open to the outside. The second silencer 129b is arranged at the end of the second exhaust pipe 135b on the side open to the outside.

The first silencer 129a and the second silencer 129b reduce the noise generated when air is emitted to the outside from the first exhaust pipe 135a and the second exhaust pipe 135b, respectively. It is a configuration that suppresses. A known configuration may be used as the first silencer 129a and the second silencer 129b.

Next, the operation of the medical device 101 having the above configuration will be described. The operation of bending the joint portion 53 is similar to that of the first embodiment, and therefore its description is omitted. Here, the operation of the medical device 101 during an emergency stop will be described.

At the time of an emergency stop, as in the first embodiment, the control unit 40 closes the control servo valve 21 and the first space 33a with respect to the first opening/closing solenoid valve 123a of the first valve device 121a. A control signal is output and a control signal for closing the space between the control servo valve 21 and the second space 33b is output to the second opening/closing solenoid valve 123b of the second valve device 121b.

After that, the control unit 40 outputs a control signal for opening the first exhaust valve 26a of the first valve device 121a and the second exhaust valve 26b of the second valve device 121b. As shown in FIG. 8, the first exhaust valve 26a to which the control signal is input makes the first space 33a of the pneumatic actuator 30 communicate with the first exhaust pipe 135a, and the second exhaust valve 26b is pneumatically connected. The second space 33b of the actuator 30 communicates with the second exhaust pipe 135b.

The air in the first space 33a passes through the first variable throttle 128a and the first silencer 129a and is discharged to the outside. The air in the second space 33b passes through the second variable throttle 128b and the second silencer 129b and is discharged to the outside.

The air pressure Pa in the first space 33a and the air pressure Pb in the second space 33b change as shown in FIG. First, in the state where the exhaust valve 26a and the exhaust valve 26b are closed, the air pressure Pa is P1, the air pressure Pb is P2, and P1>P2. From the time when the exhaust valve 26a and the exhaust valve 26b are opened, the pressures of the air pressure Pa and the air pressure Pb start to decrease. The decrease of the air pressure Pa and the air pressure Pb continues until it becomes equal to the atmospheric pressure which is the external pressure.

According to the above configuration, the first valve device 121a in which the first opening/closing solenoid valve 123a and the first exhaust valve 26a are integrally formed, and the second opening/closing solenoid valve 123b and the second exhaust valve 26b are provided. By providing the integrally formed second valve device 121b, compared with the case where the first opening/closing solenoid valve, the first exhaust valve, the second opening/closing solenoid valve and the second exhaust valve are separately arranged. It is possible to reduce the number of parts constituting the medical device 101.

By arranging the first variable throttle 128a with respect to the first exhaust valve 26a and arranging the second variable throttle 128b with respect to the second exhaust valve 26b, as compared with the case where a common throttle valve is provided. Thus, it is possible to independently control the rate of pressure decrease in the first space 33a and the second space 33b.

[Third Embodiment]
Next, a third embodiment of the present disclosure will be described with reference to FIGS. 9 and 10. The basic configuration of the medical device of this embodiment is the same as that of the first embodiment, but the configuration of the drive unit is different from that of the first embodiment. Therefore, in the present embodiment, the configuration of the drive unit will be described with reference to FIGS. 9 and 10, and description of other configurations will be omitted.

As shown in FIG. 9, the drive unit 220 of the medical device 201 according to the present embodiment includes an opening/closing solenoid valve 23, a pneumatic actuator 30, a first opening/closing side pressure sensor 25a and a second opening/closing side pressure sensor 25b. , The first exhaust valve 26a and the second exhaust valve 26b, the first check valve 27a and the second check valve 27b, and the throttle valve 228a which is the first variable throttle and the second variable throttle. A certain throttle valve 228b and a first silencer 229a and a second silencer 229b are mainly provided.

The drive unit 220 is provided with a control servo valve 21, a first servo-side pressure sensor 22a, and a second servo-side pressure sensor 22b, as in the drive unit 20 of the first embodiment. The illustration and description thereof are omitted.

The first variable throttle 228a is arranged in the first exhaust pipe 235a. The second variable throttle 228b is arranged in the second exhaust pipe 235b. More specifically, the first variable throttle 228a is arranged between the first exhaust valve 26a and the first silencer 229a in the first exhaust pipe 235a, and the second variable throttle 228b is the second variable throttle 228b. It is arranged between the second exhaust valve 26b and the second silencer 229b in the exhaust pipe 235b.

The first variable throttle 228a is configured to adjust the flow rate per unit time when air is discharged from the first exhaust pipe 235a to the outside, and the second variable throttle 228b is configured such that air is the second exhaust gas. This is a configuration for adjusting the flow rate per unit time when being discharged from the pipe 235b to the outside. Known configurations may be used as the first variable diaphragm 228a and the second variable diaphragm 228b.

The first exhaust pipe 235a is a pipe that branches from the first flow path 23a that communicates with the first space 33a of the pneumatic actuator 30 and has an end open to the outside. A first exhaust valve 26a, a first variable throttle 228a, and a first silencer 229a are arranged in the first exhaust pipe 235a.

The second exhaust pipe 235b is a pipe that is branched from the second flow path 23b that communicates with the second space 33b of the pneumatic actuator 30 and the end of which is open to the outside. A second exhaust valve 26b, a second variable throttle 228b, and a second silencer 229b are arranged in the second exhaust pipe 235b.

The first silencer 229a is arranged at the end of the first exhaust pipe 235a on the side open to the outside. The second silencer 229b is arranged at the end of the second exhaust pipe 235b on the side open to the outside.

The first silencer 229a and the second silencer 229b reduce the sound generated when the air is discharged to the outside from the first exhaust pipe 235a and the second exhaust pipe 235b, respectively, or generate the sound. It is a configuration to suppress. A known configuration may be used for the first silencer 229a and the second silencer 229b.

Next, the operation of the medical device 201 having the above configuration will be described. The operation of bending the joint portion 53 is similar to that of the first embodiment, and therefore its explanation is omitted. Here, the operation of the medical device 201 during an emergency stop will be described.

At the time of an emergency stop, as in the first embodiment, the control unit 40 closes the control servo valve 21 and the first space 33a with respect to the opening/closing solenoid valve 23, and controls the servo valve 21 and the first space 33a. A control signal for closing the space between the two spaces 33b is output.

After that, the control unit 40 outputs a control signal for opening the exhaust valve 26a and the exhaust valve 26b. As shown in FIG. 9, the exhaust valve 26a to which the control signal is input makes the first space 33a of the pneumatic actuator 30 communicate with the exhaust pipe 235a, and the exhaust valve 26b communicates with the second space 33b of the pneumatic actuator 30. It communicates with the exhaust pipe 235b.

The air in the first space 33a passes through the variable throttle 28a and the silencer 29a and is discharged to the outside. The air in the second space 33b passes through the variable throttle 28b and the silencer 29b and is discharged to the outside. The change in the air pressure Pa in the first space 33a and the change in the air pressure Pb in the second space 33b are similar to those in the second embodiment, and thus the description thereof is omitted.

According to the above configuration, by using the opening/closing solenoid valve 23 integrally formed, it is possible to reduce the number of parts constituting the medical device 201, as compared with the case of providing a plurality of opening/closing solenoid valves. Becomes

By arranging the first variable throttle 228a with respect to the first exhaust valve 26a and arranging the second variable throttle 228b with respect to the second exhaust valve 26b, as compared with the case where a common throttle valve is provided. Thus, it is possible to independently control the rate of pressure decrease in the first space 33a and the second space 33b.

Note that the technical scope of the present disclosure is not limited to the above embodiment. Various modifications can be made to the technical scope of the present disclosure without departing from the spirit of the present disclosure. For example, in the above-described embodiment, the present invention has been described by being applied to an example used for operating the forceps 52 used in endoscopic surgery, but the operation target is not limited to the forceps 52. For example, the operation target may be an instrument used for operating another surgical tool such as an electric scalpel used for endoscopic surgery.

Claims

A cylinder-shaped cylinder, and a gas pressure actuator having a piston arranged so as to be relatively movable in the axial direction of the cylinder and partitioning an internal space of the cylinder into first and second spaces,
A first flow path connected to the first space so that gas can flow in and out of the first space;
A second flow path connected to the second space such that the gas can flow in and out.
A first closing valve which is provided in the first flow path and controls the flow and cutoff of the gas supplied from the outside to the first space;
A second closing valve which is provided in the second flow path and controls the flow and cutoff of the gas supplied to the second space from the outside;
A first exhaust valve that controls exhaust and shutoff of the gas from between the cylinder and the first closing valve in the first flow path to the outside of the first flow path;
A second exhaust valve that controls exhaust and shutoff of the gas from between the cylinder and the second closing valve in the second flow path to the outside of the second flow path;
A throttle valve capable of changing the flow passage cross-sectional area of the gas exhausted from the first exhaust valve and the second exhaust valve;
A medical device characterized by being provided.
The first closing valve and the second closing valve are integrally formed closing valves,
The gas exhausted from the first exhaust valve and the second exhaust valve is guided to the same throttle valve,
A check valve that allows the flow of the gas toward the throttle valve is provided between the first exhaust valve and the throttle valve and between the second exhaust valve and the throttle valve. The medical device according to claim 1, wherein:
The first closing valve and the first exhaust valve are a first valve device formed integrally,
The second closing valve and the second exhaust valve are second valve devices formed integrally,
The gas exhausted from the first exhaust valve is guided to a first throttle valve,
The medical device according to claim 1, wherein the gas exhausted from the second exhaust valve is guided to a second throttle valve.
The first closing valve and the second closing valve are integrally formed closing valves,
The gas exhausted from the first exhaust valve is guided to a first throttle valve,
The medical device according to claim 1, wherein the gas exhausted from the second exhaust valve is guided to a second throttle valve.