WO2014088278A1

WO2014088278A1 - Actuator driven by variable piston made from soft sealing film

Info

Publication number: WO2014088278A1
Application number: PCT/KR2013/011071
Authority: WO
Inventors: 이재성
Original assignee: Lee Jae-Sung
Priority date: 2012-12-06
Filing date: 2013-12-02
Publication date: 2014-06-12
Also published as: KR101299985B1

Abstract

The present invention relates to an actuator using a phenomenon in which a soft sealing film moves reciprocally inside a pressure container while having a variable form, like a piston inside a cylinder, as the soft sealing film comes into close contact with or separates from the container. The present invention basically comprises: the pressure container which functions as a cylinder; and a variable piston comprising the soft sealing film, and a piston rod, wherein the pressure in a first pressure space (A) defined by the sealing film and the pressure container is set to be different from an n^th pressure space (N) on the outside, so that when a compressed fluid is applied the sealing film, which is separated from an inner surface of the pressure container, comes into close contact with the inner surface of the pressure container to deliver driving force to the outside through the sealing film or via the piston rod which is connected to the sealing film. As a result, the pressure container, which can have a variety of shapes and sizes compared to a conventional cylinder having a cylindrical shape, can be used as the cylinder, and the distance and speed of form change can be simultaneously increased during a process of compressing and stretching the soft sealing film through repeated contact and separation, thereby exhibiting a wide range and a high speed of movement that is not achievable by a conventional piston.

Description

Actuator driven by variable piston with soft hermetic membrane

The present invention is a technology that together with the hydraulic actuator or the hydraulic pneumatic damper using the cylinder and the piston and its application field, the flexible sealing membrane is in close contact or peeling from the inner surface of the pressure vessel by the pressure difference inside and outside the pressure vessel in a variable movement method as if the piston in the cylinder Like the present invention relates to an actuator using the phenomenon of reciprocating inside the container.

An apparatus that converts the pressure of a fluid into mechanical force and movement is an actuator, which is a combination of a conventional cylinder and a piston. There is also a diaphragm drive device as an elastic membrane type piston used for mechanical motion.

Pneumatic actuators using weak fluid pressures can be used in automatic door openers and the like. Hydraulic actuators using strong fluid pressure can also be used for joint driving of excavators and robots.

If a high tightness level is not required or only a relatively short drive width is required, a bellows using a rubber tube or a diaphragm drive using a short deformation of the elastic membrane may be used. Diaphragm drives tend to be used only in relatively short strokes, but they are especially useful when pressure-driven fluids, such as vacuum boosters in automobile brakes or flush valves in toilets, may dissipate outside the drive system after they have played their part.

The unidirectional or bidirectional actuated actuators mainly dealt with by the present invention maximize the expansion and contraction deformation of the diaphragm-like hermetic piston while exhibiting similar movements as conventional piston cylinder combinations. The prior art document introduced below relates to a pneumatic piston and a hermetic diaphragm introduced to aid the understanding of the present invention. In these prior arts, a variable piston made of a soft hermetic membrane as in the present invention is directly adhered or peeled in a pressure vessel. At the same time, it is difficult to find a structure that performs partly as a piston rod.

(Patent Document 1) Korean Registered Patent 10-0844596 Diaphragm Compressor

(Patent Document 2) Actuator Structure of Korea Patent Registration 10-1177269 Engine Turbocharger

(Patent Document 3) Korea Patent Publication 10-2008-0082046 Cylinder mounted with a port on a double tube shaft

Diaphragm actuators that follow the movement pattern by the expansion and contraction of the elastic membrane, including the prior art literature, cannot exert great force and the elastic membrane itself must act as a cylinder and a piston. There is a disadvantage that increases the risk. Also, as is well known, the piston-cylinder actuator, which has a typical sliding contact type, has a very narrow driving range compared to the total weight and volume of the structure, and the driving part must perform a sealing function to prevent leakage of the pressure fluid. This is a big disadvantage.

Literature (1) describes a typical elastic membrane actuator using pneumatics. The elastic membrane acting as a piston of a compressor is considered in consideration of the volume and weight of all the accessories surrounding it, and the conventional elastic membrane deformation limits. It has a small compression capacity that is significantly less than the overall size of. Similarly, the actuator of document (2) also produces only a reciprocating stroke (elastic drive range) of extremely small magnitude relative to the supply pressure required for driving, similarly to document (1).

Literature (3) introduces a double-acting hydraulic actuator, which is a combination of a typical rigid shaft-type piston and cylinder, which has a similar aspect to the present invention in terms of implementing double-acting drive in the form of a single-acting cylinder, but a friction surface still exists. And the reciprocating distance of the piston is also still within the limits of the prior art.

As such, the conventional hydraulic actuators, in addition to solid deformation as well as fluid deformation, are commonly accompanied by excessive volume and heavy weight, airtightness, and effort to reduce friction to satisfy a desired amount of work, a desired driving speed, and a displacement. There was no choice but to.

The present invention implements an innovative piston and cylinder structure and an actuator using the same, which overcomes the limitations of the prior art as described above. Specifically, a light weight, a wide operating range, high speed drive speed, and a low manufacturing cost are required. Is to implement an innovative pneumatic actuator.

The actuator 40 of the present invention for achieving the above technical goal includes a pressure vessel 10 serving as a cylinder and a flexible sealing membrane 20 and a piston rod 30 connected to the sealing membrane. The variable piston is the key configuration.

The main difference between the present invention and the conventional diaphragm is that the diaphragm must withstand all pressures by the elastic membrane itself, while the inelastic sealing membrane 20 of the present invention has a force that expands laterally outside the direction of movement of the piston. Is that the pressure vessel 10 supports.

This means that it can be used as a variable piston by rolling a thin, wide and elongated closed membrane incomparable with a diaphragm. Therefore, the present invention is combined with various types of pressure vessels 10 to withstand a high pressure difference that cannot be compared with a conventional diaphragm. It has a long drive stroke that can be made and can not be compared with the diaphragm. This is a key feature of the present invention that distinguishes it from all conventional elastic membrane type actuators.

The pressure vessel 10, which is one of the main components of the present invention, can be made of a relatively diverse material because less smooth processing of the inner surface is required as compared with a conventional cylinder. Including ordinary metals and synthetic resin materials, light alloys such as duralumin and reinforced plastics such as FRP are suitable for forming method and securing strength, and in the case where weight reduction is particularly important, materials having very high Young's modulus such as beryllium may be used. It is good to adopt.

On the other hand, a more important component than a pressure vessel is a flexible sealing membrane which plays a key role in the variable piston. Sealing membranes are thin and flexible, so it is basically required to be well crimped or straightened and also to ensure almost complete airtightness. In other words, the strength and airtightness should be sufficiently maintained even if the operation process of closely adhering to the inner wall of the pressure vessel and peeling it is repeated.

Although there is no theoretically perfect inelastic material, the material forming the sealing film 20 in the present invention is of sufficient strength so that the elastic displacement in the driving direction of the actuator 40 is substantially close to zero within a given load range according to the use of the product. It needs to be designed. In other words, the true elastic displacement in the present invention refers to the change in volume caused by expansion and compression of the pressure fluid (even if it is a vacuum or a fluid having a pressure close to vacuum), that is, the fluid pressure difference of the pressure fluids. The movement of the sealing membranes 20 according to the present invention seems to occur as an elastic displacement, but it does not mean that the sealing membrane 20 is stretched by itself.

Therefore, the sealing membrane 20 is formed by arranging a plurality of first synthetic fibers 21 in the driving direction so as to have a width and strength that are not substantially elastically deformed in the driving direction, that is, in the movement direction of the piston.

Here, the type of the first synthetic fiber 21 may be a high-strength fiber called a reinforcing polymer fiber or a super fiber that is in the spotlight recently. Typical high-strength fibers include aramid fibers used for tire cords and body armor, and carbon fibers having a weight of only 25% of iron but 10 times stronger than iron may be used.

In addition, low specific gravity and excellent abrasion resistance, polymer polyethylene fiber used as a rope or fishing line, polyarylate fiber called Vectran, or PBO fiber called Zylon can be sufficiently applied according to the use and grade of use of the actuator. These high-strength fibers, for example, in the actuator according to the present invention are relatively small in the pressure vessel cross-sectional area of 100 cm 2 ~ 1000 cm 2 and the internal and external pressure difference is 0.1 ~ 1.0 MPa or less when applied to a typical embodiment only a few strands to several strands In fact, it is possible to secure sufficient strength so that the elastic deformation amount is close to zero. In other words, even thinner, high-strength fibers can be spread evenly to form a thinner, thinner membrane that folds well in the circumferential direction of the pressure vessel (perpendicular to the driving direction) and is very tough in the driving direction.

For example, suppose that the Vectran fiber is spread evenly to one thickness to make an actuator with a pressure area of 100 cm2. The maximum pressure and elastic strain are calculated.

Vectran has a specific gravity of 1.4 g / cm 3 and one den of 5 denier, so the diameter of one of the balls is 0.0224 mm. The maximum tension of the vectran is 25 gf / denier, so the maximum tension of each roll is 125 gf. The inner diameter of a cylinder with a cross-section of 100cm2 is 11.28cm and the circumference is 35.45cm, so it takes 15,826ol when arranged in one layer.

The maximum tension of the sealed membrane, consisting of 15,826 Vectran fibers, reaches 1.98 ton, so the maximum pressure that can be applied in the cylinder is 3.88 MPa, which is equivalent to 38.3 atmospheres.

The elastic strain at this time is 3.8% (3.8% longer than the original fiber length), so if 0.1 MPa is applied, the elastic strain is 0.098%, which is almost zero.

For the Vectran fiber, the amount of creep is not measured when it is continuously pulled for more than one year within 50% of the maximum tension, and when used at 2.6% of the maximum tension as described above, it may sag even after decades of use. creep) does not occur.

Meanwhile, the sealing membrane additionally needs to be configured such that the second synthetic fibers 22 are arranged perpendicularly or obliquely to the direction in which the first synthetic fibers 21 are arranged. In this case, the second synthetic fibers 22 are required in the direction in which the second synthetic fibers are arranged. It is necessary to set so as to be elastically deformable. In this case, unlike the first synthetic fiber 21, the second synthetic fiber 22 is preferably a fiber having easy airtightness and flexibility rather than strength. If the sealing membrane is designed with a fiber material which does not elastically deform in the direction in which the second synthetic fibers are arranged or in the circumferential direction of the pressure vessel, the circumferential length of the sealing membrane needs to be set to the longest circumferential length in the circumferential direction of the pressure vessel.

The binding of the first synthetic fiber and the second synthetic fiber, which determines the airtightness and abrasion resistance of the sealing membrane, is suitable for general composite resins for bonding composite materials and has excellent ductility at most temperature ranges such as polymer resins for binding tire cords. It should maintain low friction properties, cracks should not occur in numerous repeated use, and it should be excellent in heat resistance and corrosion resistance because it can be exposed to various usage environments.

According to the present invention, pressure vessels having various shapes and a wide range of sizes having extremely superior degrees of freedom compared to conventional cylindrical cylinders can be used as a cylinder. Therefore, it greatly improves the freedom of design and the performance of the design in all applied technical fields regardless of vehicle, ship, aircraft, etc.

In addition, in the present invention, since the closed membrane type variable piston serving as the driving body is initially in close contact with the inner surface (mainly the inner circumferential surface or the inner surface) of the pressure vessel and moves while being peeled and deformed, it participates in the piston movement to the portion that is substantially folded and unfolded. . Therefore, in most environments, it has a wide range of motion of at least 1.5 to 2 times that of the conventional piston range, and because of the light, thin and flexible sealing membrane, the ultra-high driving speed that the conventional piston cannot follow is shown with strong driving force and close contact. Slip friction is extremely reduced because the main action is the over peeling. This makes it possible to save nearly 100% of the mirror surface processing cost of the sealing-drive part required for the conventional rigid cylinder and the rigid piston combination, and the material selection cost for matching the thermal expansion coefficient of both driving surfaces.

In addition, the present invention has the advantage that it is not necessary to arrange the piston rod on the central axis line of the vessel because the freely deformed sealing membrane may also play a role as the piston rod. This can be stacked several sealing membranes penetrating each other in one pressure vessel has the effect that is very useful to implement a multi-joint movement, such as the finger joints of the humanoid robot.

1 is a perspective view and a cross-sectional view showing the most basic embodiment of the present invention

2 is a cross-sectional view conceptually illustrating a single acting actuator embodiment which is the most basic embodiment of the present invention;

3 is a cross-sectional view conceptually illustrating a left-right double-acting actuator embodiment and an operation mechanism thereof in which the single-actuated actuators of FIGS. 2A and 2B are developed.

4 is a cross-sectional view conceptually illustrating a double acting actuator embodiment developed by combining the single acting actuators of FIGS. 2A and 2C and an operation mechanism thereof;

5 is an embodiment in which the present invention is developed into a single-acting compound coaxial drive actuator.

10: pressure vessel 11: guide

13: guide cover 20: sealing film

21: first synthetic fiber 22: second synthetic fiber

23: pressure outlet pipe 30: piston rod

40: Actuator

A: first pressure space (B = 2, C = 3, D = 4, ..)

N: nth pressure space

With reference to the embodiments of the present invention included in the drawings in order to technically support the above-mentioned solution of the present invention will be described in detail.

However, the components represented by the specific terminology in the following embodiments and their coupling structures do not limit the technical spirit inherent in the present invention.

1 illustrates an embodiment of the present invention actuator 40 in its simplest and basic cylindrical single-acting form.

Looking at the embodiment of the actuator 40 shown in Figure 1a is a variable piston consisting of a flexible sealing membrane 30 and the piston rod 30 in the pressure vessel 10, one end of which is blocked by the guide cover 13 is a guide cover It can be seen that the actuator 40 in the form of a typical cylindrical cylinder formed through the guide hole 11 formed in the center.

Referring to the cross section shown in FIG. 1B, the operating structure of the FIG. 1 embodiment is well understood.

First, the pressure vessel 10 is configured with a guide hole 11 for guiding the driving of the piston rod 30 or a guide cover 13 for guiding the driving of the sealing membrane 20 as necessary.

In addition, the pressure outlet tube 23 is formed through the guide cover 13 in the form of a soft tube attached to the inner surface or the outer surface of the sealing membrane 20.

Although it is not specified by the reference numeral because it may or may not include the piston rod 30 as needed, the variable piston is at least a portion of the sealing membrane 20 constituting it is in close contact with the inner surface of the pressure vessel (10). It is formed to be possible, and also the sealing membrane 20 drives the variable piston while at least a part (close to the inner surface of the pressure vessel) in close contact by the fluid inflow or fluid outflow from the pressure vessel 10 outside.

For reference, the pressure vessel 10 is not necessarily cylindrical, but may be formed in a non-cylindrical shape. In the case of a conventional rigid piston and a cylinder, a cylindrical cylinder for preventing stress concentration or airtight performance deterioration is the most ideal design, but the present invention does not necessarily need to be cylindrical because the soft sealing membrane 20 mostly compensates for the above-mentioned disadvantages.

And the variable piston is composed of only the sealing membrane 20, or further comprises at least one pressure outlet tube 23 attached to the sealing membrane 20, or at least connected to the sealing membrane 20 It may be configured to further include one piston rod (30). The most typical form consists of one sealing membrane and one or more piston rods, the most unusual of which is the absence of piston rods in many sealing membranes. That is, if the variable piston is designed with only a simple contraction action, it means that the piston rod 30 can be replaced by extending the sealing membrane as necessary.

In addition, although the pressure inlet and outlet pipe 23 is formed in the disk-shaped guide cover 13 in FIGS. 1A and 1B, referring to FIG. 2A, the pressure outlet and inlet pipe penetrates through the shaft center of the piston rod 30 and the pressure vessel 10. It may be connected to the inside. In other words, the pressure outflow pipe 23 has an inherent function of allowing the pressure fluid to flow in and out of the space formed by the sealing membrane 20 and the pressure vessel, that is, the sealing membrane 20 is repeatedly formed on the inner surface of the pressure vessel 10. If it does not interfere with the function of close peeling, even if installed in the guide cover, the piston rod, or any where necessary does not impair the technical idea of the present invention.

At this time, a part of the peeled sealing film 20 acts like a piston rod, and when the closed sealing film is peeled off (the length of the cylinder) and peeled off based on the simple cylindrical pressure vessel of FIG. Combined with the extension of the sealing membrane like the piston rod (extended length of the piston), the driving displacement is about twice that of the existing piston.

Meanwhile, in this process, the sealing membrane 20 is formed in a width and strength that is not elastically deformed in the driving direction of the variable piston. Referring to FIG. 1B, a plurality of first synthetic fibers 21 are arranged in the driving direction. The second synthetic fibers 22 are arranged perpendicularly or obliquely to the direction in which the first synthetic fibers 21 are arranged.

As described above, the first synthetic fiber 21 is set at a very high strength so that the sealing film does not stretch itself when pulled out, and is perpendicular to the direction in which the first synthetic fiber 21 is arranged, that is, the pressure. The second synthetic fiber 22 arranged in the circumferential direction of the container is made of a flexible material in order to be smoothly re-adhered to the inner surface of the pressure vessel at the time of return in consideration of the relatively small force is applied.

For reference, the second synthetic fiber needs to be made of a flexible material, but does not necessarily need to be elastically deformable, and may be made of an inelastic material. The important thing is to be fast, perfect and re-adherent to the inner surface of the pressure vessel without being folded when re-adhesion after peeling. If it is made of inelastic material, if the circumference or diameter of the inner surface of the pressure vessel is changed, it is designed according to the largest perimeter or diameter. It needs to be designed to fit the circumference or diameter of each corresponding point. If the pressure vessel has a large variation in cross-sectional area or circumference over the longitudinal direction, the sealing membrane uniformly formed in accordance with the largest circumference length will have many folded portions when in close contact. Therefore, it may be configured to be elastically deformable in the second synthetic fiber arrangement direction only in the portion where such design is required.

This part can be sufficiently solved by the super fibers mentioned in the above-mentioned problem solving means, and the synthetic resin binding the fiber array can also be sufficiently solved by the special polymer resin.

FIG. 2A is a cross-sectional view conceptually showing a single-acting actuator, which is the most basic embodiment of the present invention (structurally the same as FIG. 1), and FIGS. 2B and 2C conceptually illustrate a single-acting actuator embodiment modified from FIG. 2A. It is sectional drawing.

In each embodiment, when the first pressure space A is supplied with a pressure different from the nth pressure space N, which is its external space, specifically, a high pressure, the sealing membrane 20 is in a close state from the peeled state. The piston rod 30 is driven while being switched. As will be described later in FIGS. 3 to 5, the concept of such a pressure space can be continuously extended to three or four spaces.

For reference, FIGS. 2A and 2B are preferred designs when the sealing membrane is smoothly adhered to or peeled off from the inner surface of the pressure vessel without a folding section, and is suitable when heat resistance and friction resistance of the sealing membrane are required and driving reactivity is required. On the other hand, Fig. 2C is suitable when less heat resistance and friction resistance of the sealing membrane are required and more driving responsiveness is required. At this time, the plate-shaped pressure surface formed in the piston rod 30 is designed in a relatively small size that is not at all friction with the inner surface of the pressure vessel in a different concept from the conventional piston.

Although the present invention and the subject matter are not shown in the drawings, two pressure inlet and outlet pipes are formed in the single-acting actuator of FIG. 2A or 2B, and the piston rod is driven with a check valve driven in one direction in the suction and discharge directions, respectively. If so, this could be a compressor or inhaler, as opposed to an actuator.

When the fluid inside the pressure vessel is compressed or expanded by the driving force of the piston rod, the fluid sucked through the pressure inlet tube may be discharged to the pressure outlet tube while being compressed by the sealing membrane. This means that the present invention can be used by changing the design of a fluid pump such as a vacuum pump or an air compression pump, not an actuator for driving the piston rod by the force of the pressure fluid.

3 is a cross-sectional view conceptually illustrating a left-right double-acting actuator embodiment and an operating mechanism thereof in which the single-actuated actuators of FIGS. 2A and 2B are developed.

Two or more sealing films 20 may be stacked and arranged as necessary. That is, in the drawing, the closed space formed by the variable piston and the pressure vessel 10 is denoted as the first pressure space A and the pressure vessel external space is denoted as the nth pressure space N. Is expanded to the first pressure space (A), the second pressure space (B), the third pressure space (C) and the like, the outermost space may be defined as the n-th pressure space (N).

The first to nth pressure spaces A to N expand or contract in the same direction or expand or contract in different directions within the pressure vessel 10. The characteristics of such a pressure space can be basically defined in FIGS. 4 and 5 to be described later.

The configuration of FIG. 3 can be applied to a typical reciprocating actuator. The difference from conventional pneumatic piston-cylinder is that it can be made very cheap, very light and small because there is no need for precision machining. It also boasts extremely fast reciprocating speeds. This characteristic means that the number of cranks that reciprocate rapidly can be significantly increased in the environment in which positive or negative air is continuously generated, or vice versa. The former application could be a pneumatic hammer used in small factories, and in the latter case it would be a cheap and efficient air compressor by connecting multiple actuators in FIG. 3 to one reciprocating crank.

* On the other hand, when the total length of the portion close to the sealing membrane in the pressure vessel 10 is L, it can be seen that the driving displacement of the variable piston is at least twice that of L, considering the peeling portion of the sealing membrane. 2 and 3, since the cross-sectional area of the pressure vessel is constant, the drive stroke of the variable piston is about twice that of a conventional rigid piston drive stroke.

4 is a cross-sectional view conceptually illustrating a bipolar contraction expansion actuator embodiment and an operation mechanism thereof developed by combining the single-acting contractive actuator of FIG. 2A and the single-acting inflatable actuator of FIG. 2B.

4 can perform not only the contraction of the typical biological muscles but also vice versa. Light weight, high speed, and low cost of processing are inherent in the present invention. After all, the case shown in Figure 4 is the most ideal actuator for small-light-speed high-speed moving objects, such as bird wings and insect jumps. When you want to make an actuator that allows you to reciprocate quickly or squeeze quickly and lightly, and make a lot of light, cheap and expensive, the airtight membrane made of a simple composite synthetic resin and ultra thin super fiber is more than any combination of metal cylinder type piston cylinders. Outstanding performance and reliability without leakage of pneumatic pressure even in long term operation.

5 is an embodiment in which the present invention is developed into a single-acting coaxial drive actuator, and the actuator of the present invention introduces an embodiment of an elastic actuator in which the present invention is most innovatively applied.

The pressure outflow pipe 23 is connected to the pressure vessel 10 to allow the pressure fluid to flow in and out of the space formed by the sealing membrane and the pressure vessel. More specifically, the flexible guide cover 13 plays a key role in allowing a plurality of coaxially arranged sealing membranes to extend as they are and serve as a tensioning rope such as a piston rod.

The pressure vessel 10 may be formed to change the pressure action area of the pressure received from the first pressure space or the nth pressure space according to the driving displacement of the variable piston, and at this time, the projection in which the pressure action area is projected in the displacement direction. The area may be circular (or isotropic regular polygonal) shape as in FIG. 1 or any shape that is not cylindrical as in FIG.

Since the driving force at a particular drive displacement is determined by the working area of the pressure fluid at that point, the design of the pressure vessel 10 intentionally places a pressure increasing (or decreasing) space 12 at some drive displacement as shown in FIG. 5B. If it is designed to change the pressure action area, various driving force can be obtained according to the displacement of the variable piston.

On the other hand, the sealing membrane is arranged in at least two layers or more inside the pressure vessel 10 and deformed while being peeled off or in close contact with each other independently.

Therefore, a plurality of pressure spaces are secured between the sealing membranes arranged in layers at intentionally set intervals. As described above, if the closed space formed by the variable piston and the pressure vessel 10 is the first pressure space A and the outer space of the pressure vessel is the nth pressure space N, the pressure space is equal to three when the closed membrane is three. The first pressure space A, the second pressure space B, and the third pressure space C may be expanded and the nth pressure space N, which is the outermost space, may be a pressure space filled with a body fluid, not a vacuum. .

Of course, since the pressure vessel 10 and the sealing membrane or between the plurality of sealing membranes further comprises a pressure outflow pipe 23 for performing the inflow and outflow of the pressure fluid, the first, second, third pressure space As the pressure flow inlet pipe 23, the fluid of different pressure may flow in and out.

Some pressure fluid may leak between the soft guide cover 13 and the outermost sealing membrane 20 or between the gaps penetrated between the sealing membrane and the sealing membrane. However, considering that the ligament penetrates into the fascia, a design that can never be realized with a piston rod made of a rigid body, rather than the disadvantages caused by the leakage of pressure fluid, the sealing membranes overlap each other in the state of overlapping the sealing membranes. The advantage is that even greater. For example, when designing a humanoid robot, there may be a method in which the inside of the skin (the entire outer space of the pressure vessel) is filled with a pressure fluid, and a slight leak is reprocessed in a closed system inside the skin and resupplied by a compression pump. In this design, if only the airtightness of the envelope surrounding the joints and muscles (actuator) is properly maintained, the leakage of pressure fluid between the sealing membrane and the sealing membrane and the soft guide cover and the sealing membrane is minimized, and the actuator is inherently unloaded. The driving force of can fully be exhibited.

As a result, if the airtightness of the sealing membrane which is not completely sealed by the guide cover 13 or the external body fluid or the like is compensated to some extent (if the leakage of the pressure fluid is a slight loss compared to the driving force gain effect), the actuator of the present invention is never used as a conventional piston. It is possible to construct a coaxially arranged piston that cannot be attempted and as shown in FIGS. 5C and 5D, it is possible to fully implement the winging motion of a bird or to perform a motion similar to a human finger. This process is similar to the movement between the fascia and the fascia in contact with each other and the blood supply through the blood vessels between them. Further developing the configuration as shown in Figure 5 is a microscopic, ultra-thin sealing membrane made of several strands of fibers to implement a multi-joint muscle, such as the body of the snake or legs of the insect as the actuator 40 of the present invention That means you can.

While the embodiments of the present invention have been described in detail with reference to the drawings, the technical spirit of the present invention is not limited to the above embodiments.

In other words, one of ordinary skill in the art to which the present invention pertains may utilize a technical idea implied by the present invention to implement a simple change or simple extension case, which is not included in the specification and drawings as necessary. It is also clearly included in the scope of the technical idea of the present invention expressed by the following claims.

The present invention can be applied to various actuators by modifying the shape and size of the pressure vessel.

Typical flat objects, such as flap drives or airfoils in ultralight aircraft, are ideal for implantable artificial muscles or humanoid robots that require narrow design space, relatively large forces, and require highly complex multi-stage movements. It can be used as a joint drive.

It is also well suited for new types of ultra-lightweight aircraft or insect robots that make winged movements when combined with small, lightweight pneumatic power sources.

For reference, although not claimed as a right in the present invention, when the actuator of the present invention is designed and modified to form an elastic structure used for compressive expansion of a hermetic fluid, the coil spring of an automobile may be replaced, and the electronic device or the device may be suspended by a ceiling. It is useful as a hanger for surgical instruments and can be used as an ultra-lightweight trampoline or a lifesaving mat that can be folded and carried.

In addition, the high-speed motion performance of the present invention can be very useful as the firing power of all kinds of low noise projectiles, including bows and catapults.

Claims

Cylindrical or non-cylindrical pressure vessel 10 that serves as a cylinder; And

A variable piston including at least one soft sealing membrane 20; and

And at least one pressure inlet and outlet pipe 23 through which the pressure fluid flows in and out of the space formed by the sealing membrane 20 and the pressure vessel.

The sealing membrane is at least partially adhered to or peeled off from the outside of the pressure vessel 10 by contacting the inner surface of the pressure vessel 10, and at least a part of the peeled portion is adhered to the inner surface of the pressure vessel. Configured to drive the variable piston,

The variable piston is an actuator, characterized in that it comprises at least one piston rod (30) consisting of only the sealing membrane (20) or connected to the sealing membrane (20).
The method of claim 1,

Actuator (40) is characterized in that the sealing membrane (20) does not elastically deform in the driving direction of the variable piston.
The method of claim 2,

The first pressure space A formed by the variable piston and the pressure vessel 10 has an actuator 40 set to a different pressure from the second pressure space n-th pressure spaces B to N, which are external spaces thereof. .
The method of claim 3,

The first to n-th pressure space (A ~ N) is an actuator (40), characterized in that formed in the pressure vessel (10) in the same direction to expand or contract with each other, or to expand and contract in different directions.
The method of claim 4, wherein

The pressure vessel 10 further comprises a guide hole 11 for guiding the driving of the piston rod 30 or a guide cover 13 for guiding the driving of the sealing membrane 20. .
The method of claim 5,

The variable piston further comprises at least one pressure outlet pipe 23 attached to the sealing membrane 20,

The pressure outflow tube 23 is an actuator 40, characterized in that formed through the guide cover 13 in the form of a flexible tube attached to the inner surface or the outer surface of the sealing membrane (20).
The method of claim 2,

The sealing membrane 20 is an actuator 40 is composed of a plurality of first synthetic fibers 21 are arranged in the driving direction.
The method of claim 7, wherein

The sealing membrane (20) is an actuator (40), characterized in that the elastic or inelastic second synthetic fibers 22 are arranged perpendicularly or obliquely to the direction in which the first synthetic fibers 21 are arranged.
The method of claim 3,

The pressure vessel (10) is an actuator (40) is formed so that the pressure action area of the pressure received from the first pressure space (A) to the n-th pressure space (N) in accordance with the drive displacement of the variable piston.