Three-cavity molecular spring vibration isolation device with quasi-zero stiffness characteristic

Abstract

The invention discloses a three-cavity type molecular spring vibration isolation device with the quasi-zero stiffness characteristic. The three-cavity type molecular spring vibration isolation device comprises a molecular spring, a one-way valve, a horizontal distribution bullet cavity, sealing rubber, a force transmission guide column, a vertical molecular spring cavity and a piston rod. The top of the piston rod is used for connecting a vibration-isolated object, and the bottom is provided with a protruding cylindrical face making contact with the cylindrical end face of the force transmission guide column. A molecular spring in the vertical molecular spring cavity bears a vibration isolation object through a piston rod and provides positive rigidity; the molecular spring in the horizontal molecular spring cavity is subjected to pre-pressure applied by the one-way valve, and when the piston rod deviates from the balance position and vibrates, negative rigidity is provided for the piston rod through the force transmission guide column; by adjusting the positive and negative stiffness of the molecular spring cavity, the vibration isolation object can be in a quasi-zero stiffness state at a balance position. The quasi-zero-stiffness device is used for low-frequency vibration isolation, miniaturization of the quasi-zero-stiffness device can be achieved through the extremely high bearing capacity of the molecular spring, and the requirement of the quasi-zero-stiffness device for the installation space is lowered.

Description

Technical Field

[0001] The invention relates to a technology in the field of vibration isolation, and in particular to a vibration isolation three-cavity molecular spring vibration isolation device with quasi-zero stiffness characteristics. Background Art

[0002] Traditional passive vibration isolators are linear systems, which are constrained by the contradictory relationship between load-bearing capacity and natural frequency (the effective vibration isolation frequency of traditional linear vibration isolators is greater than 1.4 times the natural frequency), and it is difficult to effectively isolate low-frequency vibrations. Quasi-zero stiffness isolators are a typical nonlinear stiffness vibration isolation system, which connects negative stiffness elements in parallel with positive stiffness elements to obtain high static stiffness and near-zero dynamic stiffness characteristics. It has a low natural frequency near the equilibrium position, and thus has excellent low-frequency vibration isolation performance. For this reason, there is an urgent need to innovatively design quasi-zero stiffness vibration isolation devices based on new materials and new structures. Molecular springs are a liquid-solid mixed medium that not only has the same excellent mechanical properties as air springs, but also has the significant advantages of reliable structure and small size. Therefore, it is of significant value to design a quasi-zero stiffness vibration isolation device based on molecular springs. Summary of the invention

[0003] The purpose of the present invention is to provide a three-cavity molecular spring vibration isolation device with quasi-zero stiffness characteristics, which utilizes the extremely strong load-bearing capacity of the molecular spring to achieve the miniaturization of the quasi-zero stiffness device, reduce the demand for installation space of the quasi-zero stiffness device, and realize the demand of the vibration isolation object for the quasi-zero stiffness vibration isolation device in a small space.

[0004] To achieve the above object, the present invention adopts the following technical solutions:

[0005] A three-chamber molecular spring vibration isolation device with quasi-zero stiffness characteristics includes a molecular spring, a one-way valve, a horizontal molecular spring chamber, a sealing rubber, a force transmission guide column, a vertical molecular spring chamber and a piston rod. The top of the piston rod is used to connect to the object to be isolated, and the bottom is provided with a raised cylindrical surface that contacts the cylindrical end face of the force transmission guide column; the molecular spring in the vertical molecular spring chamber carries the isolation object through the piston rod and provides positive stiffness; the molecular spring in the horizontal molecular spring chamber is subjected to the pre-pressure applied by the one-way valve, and when the piston rod vibrates from the equilibrium position, the force transmission guide column provides negative stiffness in the vertical direction to the piston rod; reasonable adjustment of the positive and negative stiffness of the molecular spring chamber can realize that the isolation object is in a quasi-zero stiffness state when in the equilibrium position; there is one one-way valve on the left and right sides, which is fixed to the left and right horizontal molecular spring chambers by threads. It is used to provide the required pre-pressure in the horizontal molecular spring cavity; the horizontal molecular spring cavity is a stepped cylindrical cavity, and the inner end faces of the left and right horizontal molecular spring cavities are coaxially installed on the corresponding side faces of the vertical molecular spring cavity through bolts, and the side openings of the vertical molecular spring cavity are sealed by a sealing rubber sheet, and the outer end face is used to connect the one-way valve; the vertical molecular spring cavity is an open metal cavity with a square outside and a round inside, and cylindrical through holes for installing force transmission guide columns are arranged on the left and right sides, and the upper end face of the opening is fastened to the sealing seat by bolts; the sealing seat is also a stepped cylindrical cavity, and the central through hole of the sealing seat is used for sealing and guiding the piston rod.

[0006] The horizontal molecular spring cavity is a stepped cylindrical cavity. The left and right horizontal molecular spring cavities are coaxially installed and fixedly connected to the left and right sides of the vertical molecular spring cavity with bolts. The outer end face of the horizontal molecular spring cavity is fastened to the one-way valve through a thread. A sealing groove is arranged on the inner side. The inner end face is sealed by the sealing rubber in the groove. The molecular spring material is sealed in the horizontal molecular spring cavity. The pressure in the horizontal molecular spring cavity is increased to the working pressure (the piston rod is in a static equilibrium position at this time) through the one-way valve, so that the horizontal molecular spring is in a compressed state. When the piston rod deviates from the equilibrium position and vibrates up and down, the compressed horizontal molecular spring transmits the restoring force to the piston rod through the force transmission guide column. In this process, the horizontal molecular spring provides negative stiffness.

[0007] The one-way valve is a valve that can inject water in one direction.

[0008] The sealing rubber is a cylindrical shell with a boss on the edge. The boss on the edge is embedded in the sealing groove on the inner end face of the horizontal molecular spring cavity. The sealing rubber and the one-way valve seal the end face of the horizontal molecular spring. When the piston rod deviates from the equilibrium position and vibrates up and down, the sealing rubber can push the force transmission guide column to move into the vertical molecular spring cavity due to the elastic force provided by the molecular spring.

[0009] The force transmission guide column is a cylinder with an arc surface on the inner side, which is built into the through hole on the side of the vertical molecular spring cavity. The arc surface of the force transmission guide column contacts the raised arc surface of the piston rod, and can transmit the elastic force of the horizontal molecular spring to the piston rod through the contact point. Due to the arc contact, the elastic restoring force of the horizontal molecular spring will decompose into a force parallel to the piston rod. This force is the mechanism for generating the negative stiffness of the quasi-zero stiffness molecular spring.

[0010] The vertical molecular spring cavity is an open metal cavity with a square outside and a circular inside, and the cavity is filled with molecular spring materials. Circular through holes for installing force transmission guide pillars are arranged on the left and right sides of the metal cavity, and circumferentially arranged threaded holes are arranged on the upper end face of the opening. A sealing groove is arranged on the inner side of the threaded hole. The upper end face of the vertical molecular spring cavity is fastened to the sealing seat by bolts, and the end of the piston rod with an outer convex arc surface is placed in the vertical molecular spring cavity. When the vibration isolation object is placed on the upper end of the piston rod and is in a static equilibrium position, the molecular spring in the vertical molecular spring cavity provides elastic supporting force. When the piston rod deviates from the equilibrium position and vibrates up and down, the molecular spring in the vertical molecular spring cavity provides elastic restoring force, and the restoring force is manifested in the form of positive stiffness.

[0011] The sealing seat is a stepped cylinder with evenly distributed through holes on the edge of the cylinder, a central through hole on the boss at the center of the cylinder, a sealing groove on the inner side of the central through hole, and the sealing seat cooperates with the sealing ring to seal the upper end of the vertical molecular spring cavity and the piston rod.

[0012] The piston rod is a cylinder with a convex arc surface near the bottom. The convex arc surface of the piston rod contacts the arc surface of the force transmission guide column. When the piston rod is in a static equilibrium position, the piston rod is only affected by the elastic force of the molecular spring in the vertical molecular spring cavity. When the piston rod deviates from the equilibrium position and vibrates up and down, the piston rod is simultaneously affected by the elastic force of the molecular springs in the horizontal molecular spring cavities on the left and right sides and the elastic force of the molecular spring in the vertical molecular spring cavity. The force in the horizontal direction presents negative stiffness, and the force in the vertical direction presents positive stiffness. Since the positive and negative stiffnesses offset each other, the quasi-zero stiffness of the attachment in the static equilibrium position is achieved.

[0013] The beneficial effects of the present invention are as follows:

[0014] The present invention utilizes the extremely strong bearing capacity of the molecular spring to realize the miniaturization of the quasi-zero stiffness device, reduces the demand of the quasi-zero stiffness device for installation space, and realizes the demand of the vibration isolation object for the quasi-zero stiffness vibration isolation device in a narrow space. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a structural schematic diagram of the present invention;

[0016] Figure 2 It is the cross-sectional view of the left horizontal molecular spring cavity;

[0017] Figure 3 is a cross-sectional view of the left sealing rubber;

[0018] Figure 4 is a schematic diagram of a force transmission guide column;

[0019] Figure 5 is a cross-sectional view of the vertical molecular spring cavity;

[0020] Figure 6 is a cross-sectional view of the sealing seat;

[0021] Figure 7 is a cross-sectional view of the piston rod;

[0022] Figure 8 It is the cross-sectional view of the mechanism when no load is applied;

[0023] Fig. 9 It is the cross-sectional view of the mechanism in the static equilibrium position;

[0024] In the figure, 1_1-molecular spring; 1_2-left molecular spring; 1_3-right molecular spring; 2_1-left one-way valve; 2_2-right one-way valve; 301_1-left horizontal molecular spring chamber; 302_1-left chamber end face internal thread; 303_1-left chamber end face edge through hole; 304_1-left chamber end face sealing groove; 301_2-right horizontal molecular spring chamber; 401_1-left sealing rubber; 402_1-left sealing rubber edge boss; 401_2-right sealing rubber; 501_1-left force transmission guide column; 502_1- Arc surface of force transmission guide column; 501_2-right force transmission guide column; 601-vertical molecular spring chamber; 602-vertical chamber side through hole; 603-vertical chamber side threaded hole; 604-vertical chamber top threaded hole; 605-vertical chamber top sealing groove; 606-center chamber; 7-first sealing ring; 801-piston rod; 802-outer convex arc surface; 9-second sealing ring; 1001-sealing seat; 1002-sealing seat edge through hole; 1003-sealing seat center boss; 1004-side sealing groove; 1005-center through hole. DETAILED DESCRIPTION

[0025] The present invention will be further explained below in conjunction with the accompanying drawings.

[0026] like Figure 1The three-chamber molecular spring vibration isolation device with quasi-zero stiffness characteristics of the present invention is shown, including a molecular spring, a one-way valve, a horizontal molecular spring chamber, a sealing rubber, a force transmission guide column, a vertical molecular spring chamber, a sealing seat, a sealing ring and a piston rod. The top of the piston rod is used to connect the object to be isolated, and the bottom is provided with a raised cylindrical surface that contacts the cylindrical end face of the force transmission guide column; the molecular spring in the vertical molecular spring chamber carries the isolation object through the piston rod and provides positive stiffness; the molecular spring in the horizontal molecular spring chamber is subjected to the pre-pressure applied by the one-way valve, and when the piston rod vibrates from the equilibrium position, the negative stiffness in the vertical direction is provided to the piston rod through the force transmission guide column; there is one one-way valve on the left and right sides, which is fixedly connected to the left and right horizontal molecular spring chambers by threads, and is used to provide the required pre-pressure in the horizontal molecular spring chamber; the size of the positive and negative stiffness of the molecular spring chamber can be reasonably adjusted The vibration isolation object is in a quasi-zero stiffness state when in the equilibrium position; the horizontal molecular spring cavity is a stepped cylindrical cavity, and the inner end faces of the left and right horizontal molecular spring cavities are coaxially installed on the corresponding side faces of the vertical molecular spring cavity by bolts, and the side openings of the vertical molecular spring cavity are sealed by a sealing rubber sheet, and the outer end face is used to connect the one-way valve; the vertical molecular spring cavity is an open metal cavity with a square outside and a round inside, and the left and right sides are provided with cylindrical through holes for installing force transmission guide columns, and the upper end face of the opening is fastened to the sealing seat by bolts; the sealing seat is also a stepped cylindrical cavity, and the central through hole of the sealing seat is used for sealing and guiding the piston rod. The present invention utilizes the extremely strong load-bearing capacity of the molecular spring to realize the miniaturization of the quasi-zero stiffness device, reduce the demand for installation space of the quasi-zero stiffness device, and realize the demand of the vibration isolation object for the quasi-zero stiffness vibration isolation device in a small space.

[0027] like Figure 2As shown, the left horizontal molecular spring includes a left horizontal molecular spring cavity 301_1, a left cavity end face internal thread 302_1, a left cavity end face edge through hole 303_1, and a left cavity end face sealing groove 304_1. The left horizontal molecular spring cavity 301_1 is a stepped cylindrical cavity, which is coaxially installed with the right horizontal molecular spring cavity 301_2 and fixedly connected to the left and right sides of the vertical molecular spring cavity 601 with bolts. The outer end face of the left horizontal molecular spring cavity 301_1 is fastened to the left one-way valve 2_1 through a thread, and a left cavity end face sealing groove 304_1 is set on the inner end face, and the inner end face sealing is realized by the left sealing rubber 401_1 in the groove. The left molecular spring 1_3 material is sealed in the left horizontal molecular spring cavity 301_1, and the right molecular spring 1_3 is sealed in the right horizontal molecular spring cavity 301_2. 2 material, and the pressure in the horizontal molecular spring cavity (left horizontal molecular spring cavity 301_1, right horizontal molecular spring cavity 301_2) is increased to the working pressure (at this time, the piston rod 801 is in a static equilibrium position) through the one-way valve (left one-way valve 2_1, right one-way valve 2_2), so that the horizontal molecular spring is in a compressed state. When the piston rod 801 deviates from the equilibrium position and vibrates up and down, the compressed horizontal molecular spring transmits the restoring force to the piston rod 801 through the force transmission guide column (left force transmission guide column 501_1, right force transmission guide column 501_2). In this process, the horizontal molecular spring provides negative stiffness.

[0028] like Figure 3 As shown, the left sealing rubber 401_1 is a cylindrical shell with a left sealing rubber edge boss 402_1 set on the edge. The left sealing rubber edge boss 402_1 is embedded in the left cavity end face sealing groove 304_1 on the inner end face of the left horizontal molecular spring cavity 301_1. The sealing rubber (left sealing rubber 401_1, right sealing rubber 401_2) and the one-way valve (left one-way valve 2_1, right one-way valve 2_2) seal the end face of the horizontal molecular spring. When the piston rod 801 deviates from the equilibrium position and vibrates up and down, due to the elastic force provided by the molecular spring, the sealing rubber (left sealing rubber 401_1, right sealing rubber 401_2) can push the force transmission guide column (left force transmission guide column 501_1, right force transmission guide column 501_2) to move inside the vertical molecular spring cavity 601.

[0029] like Figure 4 As shown, the left force transmission guide column 501_1 is a cylinder with a force transmission guide column arc surface 502_1 arranged on the inner side, which is built into the vertical cavity side through hole 602 on the side of the vertical molecular spring cavity 601. The force transmission guide column arc surface 501_1 contacts with the raised outer convex arc surface 802 of the piston rod 801, and can transmit the elastic force of the horizontal molecular spring to the piston rod 801 through the contact point. Due to the arc contact, the elastic restoring force of the horizontal molecular spring will decompose into a force parallel to the piston rod 801, and this force is the mechanism for generating the negative stiffness of the quasi-zero stiffness molecular spring.

[0030] like Figure 5 As shown, the vertical molecular spring cavity 601 is an open metal cavity with a square outside and a round inside, having a central cavity 606, the cavity is filled with molecular spring 1_1 materials, and the left and right sides of the metal cavity are provided with circular vertical cavity side through holes 602 for installing force transmission guide pillars (left force transmission guide pillar 501_1, right force transmission guide pillar 501_2), and the vertical cavity side threaded holes 603 are used for fixed connection with the horizontal molecular spring cavity, and the upper end surface of the opening is provided with circumferentially arranged vertical cavity top threaded holes 604, and the inner side of the threaded holes is provided with a vertical cavity top sealing groove 605, and the vertical molecular spring cavity is provided with a vertical cavity top sealing groove 605. The upper end surface of the spring chamber 601 is fastened to the sealing seat 1001 by bolts, and a first sealing ring 7 is arranged between the two. The piston rod 801 has an outer convex arc surface 802, and one end of the piston rod is placed in the vertical molecular spring chamber 601. When the vibration isolation object is placed on the upper end of the piston rod 801 and is in a static equilibrium position, the molecular spring in the vertical molecular spring chamber 601 provides an elastic supporting force. When the piston rod 801 deviates from the equilibrium position and vibrates up and down, the molecular spring in the vertical molecular spring chamber 601 provides an elastic restoring force, which is manifested in the form of positive stiffness.

[0031] like Figure 6 As shown, the sealing seat 1001 is a stepped cylinder, and evenly distributed sealing seat edge through holes 1002 are set on the edge of the cylinder, and a central through hole 1005 is set on the central boss 1003 of the sealing seat at the center of the cylinder. A side sealing groove 1004 is set on the inner side of the central through hole 1005. The sealing seat 1001 cooperates with the second sealing ring 9 to seal the upper end of the vertical molecular spring chamber 601 and the piston rod 801.

[0032] like Figure 7 As shown, the piston rod 801 is a cylinder with an outer convex arc surface 802 arranged near the bottom. The outer convex arc surface 802 of the piston rod 801 contacts the arc surface 502_1 of the force transmission guide column. When the piston rod 801 is in a static equilibrium position, the piston rod 801 is only acted upon by the elastic force of the molecular spring in the vertical molecular spring cavity 601. When the piston rod 801 deviates from the equilibrium position and vibrates up and down, the piston rod 801 is simultaneously acted upon by the elastic force of the molecular spring in the left and right horizontal molecular spring cavities (the left horizontal molecular spring cavity 301_1 and the right horizontal molecular spring cavity 301_2) and the elastic force of the molecular spring in the vertical molecular spring cavity 601. The force in the horizontal direction presents negative stiffness, and the force in the vertical direction presents positive stiffness. Since the positive and negative stiffnesses offset each other, the quasi-zero stiffness of the attachment in the static equilibrium position is achieved.

[0033] like Figure 8 As shown, when no load is applied, the center line of the convex arc surface 802 of the piston rod of the quasi-zero stiffness three-chamber molecular spring vibration isolation transposition is located above the center line of the arc surface 502_1 of the force transmission guide column;

[0034] like Fig. 9As shown, the center line of the piston rod arc surface 802 of the quasi-zero stiffness three-chamber molecular spring vibration isolation transposition in a static equilibrium position coincides with the center line of the force transmission guide column arc surface 502_1.

[0035] In summary, the present invention discloses a three-chamber molecular spring vibration isolation device with quasi-zero stiffness characteristics, including a molecular spring, a one-way valve, a horizontal molecular spring chamber, a sealing rubber, a force transmission guide column, a vertical molecular spring chamber, a sealing seat, a sealing ring and a piston rod. The top of the piston rod is used to connect the object to be isolated, and the bottom is provided with a raised cylindrical surface that contacts the cylindrical end face of the force transmission guide column; the molecular spring in the vertical molecular spring chamber carries the isolation object through the piston rod and provides positive stiffness; the molecular spring in the horizontal molecular spring chamber is subjected to the pre-pressure applied by the one-way valve, and when the piston rod vibrates from the equilibrium position, the negative stiffness in the vertical direction is provided to the piston rod through the force transmission guide column; there is one one-way valve on the left and right sides, which is fixedly connected to the left and right horizontal molecular spring chambers by threads, and is used to provide the required pre-pressure in the horizontal molecular spring chamber; the size of the positive and negative stiffness of the molecular spring chamber can be reasonably adjusted The vibration isolation object is in a quasi-zero stiffness state when in the equilibrium position; the horizontal molecular spring cavity is a stepped cylindrical cavity, and the inner end faces of the left and right horizontal molecular spring cavities are coaxially installed on the corresponding side faces of the vertical molecular spring cavity by bolts, and the side openings of the vertical molecular spring cavity are sealed by a sealing rubber sheet, and the outer end face is used to connect the one-way valve; the vertical molecular spring cavity is an open metal cavity with a square outside and a round inside, and the left and right sides are provided with cylindrical through holes for installing force transmission guide columns, and the upper end face of the opening is fastened to the sealing seat by bolts; the sealing seat is also a stepped cylindrical cavity, and the central through hole of the sealing seat is used for sealing and guiding the piston rod. The present invention utilizes the extremely strong load-bearing capacity of the molecular spring to realize the miniaturization of the quasi-zero stiffness device, reduce the demand for installation space of the quasi-zero stiffness device, and realize the demand of the vibration isolation object for the quasi-zero stiffness vibration isolation device in a small space.

[0036] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A three-cavity molecular spring vibration isolation device with quasi-zero stiffness characteristics, characterized in that: It includes a molecular spring, a one-way valve, a horizontal molecular spring cavity, a sealing rubber, a force transmission guide column, a vertical molecular spring cavity and a piston rod; the top of the piston rod is used to connect the vibration-isolated object, and the bottom is provided with a raised cylindrical surface that contacts the cylindrical end surface of the force transmission guide column; the molecular spring in the vertical molecular spring cavity carries the vibration-isolated object through the piston rod and provides positive stiffness; the horizontal molecular spring cavity is symmetrically installed on the side of the vertical molecular spring cavity, the one-way valve is installed on the outer end of the horizontal molecular spring cavity, and is used to provide the required pre-pressure in the horizontal molecular spring cavity, the inner end of the horizontal molecular spring cavity is isolated from the force transmission guide column by the sealing rubber, the inner end of the force transmission guide column is a cylindrical end surface, which extends into the vertical molecular spring cavity, when the piston rod vibrates from the equilibrium position, the molecular spring in the horizontal molecular spring cavity is subjected to the pre-pressure applied by the one-way valve, and provides negative stiffness in the vertical direction to the piston rod through the force transmission guide column; by adjusting the positive stiffness of the vertical molecular spring cavity and the negative stiffness of the horizontal molecular spring cavity, the vibration-isolated object is in a quasi-zero stiffness state when in the equilibrium position.

2. The three-cavity molecular spring vibration isolation device with quasi-zero stiffness characteristics according to claim 1, characterized in that: The horizontal molecular spring cavity is a stepped cylindrical cavity, which is divided into two left and right parts, and is filled with molecular spring materials. The inner end faces of the left and right horizontal molecular spring cavities are coaxially installed on the corresponding side faces of the vertical molecular spring cavity. The corresponding side faces of the vertical molecular spring cavity are provided with side openings, which are sealed by sealing rubber. The force transmission guide column is movably arranged in the side openings. The outer end face of the horizontal molecular spring cavity is connected to the one-way valve, and the inner side is isolated from the force transmission guide column by the sealing rubber.

3. The three-cavity molecular spring vibration isolation device with quasi-zero stiffness characteristics according to claim 1 is characterized in that: The vertical molecular spring cavity is an open metal cavity with a square outside and a round inside, and side openings are arranged on the left and right sides. The side openings are cylindrical through holes for installing force transmission guide columns.

4. The three-cavity molecular spring vibration isolation device with quasi-zero stiffness characteristics according to claim 3 is characterized in that: The upper end surface of the opening is fixedly connected with a sealing seat, which is a stepped cylindrical cavity. A central through hole for sealing and guiding the piston rod is arranged at the center of the sealing seat.

5. The three-cavity molecular spring vibration isolation device with quasi-zero stiffness characteristics according to claim 1, characterized in that: The sealing rubber is a cylindrical shell with a boss arranged on the edge, and the boss on the edge is embedded in the sealing groove on the inner end surface of the horizontal molecular bullet cavity.

6. The three-cavity molecular spring vibration isolation device with quasi-zero stiffness characteristics according to claim 1, characterized in that: The force transmission guide column is a cylinder with an arc surface arranged on the inner side, and the arc surface of the force transmission guide column contacts the convex cylindrical surface of the piston rod.

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