Patent No.:CN113007255A Date:2021-04-27

Google Patent: https://patents.google.com/patent/CN113007255A/en?oq=CN113007255A

China Patent: http://epub.cnipa.gov.cn/

A Threaded Groove Damping Device

Abstract

The present invention provides a threaded groove damping gas spring. The gas spirng comprises a piston assembly and a closed cavity. There is a gap between the piston assembly and the closed cavity, and a sealing member is arranged in the closed cavity to seal the gap between the piston assembly and the closed cavity. The piston assembly includes a piston body and a piston sleeve. A damping structure and a first flow-through hole are provided on the piston body. The damping structure is a threaded damping groove, which is arranged circumferentially around the piston body. A second flow-through hole is provided on the piston sleeve, and the second flow-through hole is in communication with both the damping structure and the first flow-through hole. Since this super-long damping structure is arranged circumferentially around the piston body, the damping stroke is effectively extended, enabling the movement of the piston assembly to be smooth, ensuring the smooth spring-back speed of the damping device. The design concept is ingenious. At the same time, the safety and service life are greatly improved, thus solving the problems of traditional gas springs, such as fast movement speed, and inability to effectively ensure their safety and service life.

Description

Technical Field

The present invention relates to the field of gas springs, and specifically to a threaded groove damping device.

Background Art

Gas springs are components that can achieve functions such as support, buffering, braking, height and angle adjustment. In construction machinery, they are mainly applied to parts such as covers and doors. A gas spring mainly consists of a piston rod, a piston, a sealing guide sleeve, a filler, a pressure cylinder, a joint, etc. The pressure cylinder is a closed cavity, filled with inert gas or an oil – gas mixture inside, and the pressure in the cavity is several or dozens of times that of the atmospheric pressure.
Traditional gas springs are filled with gas at a certain pressure in the cylinder. Due to the difference in cross – sectional areas at both ends, a pressure difference is generated, causing the side with higher pressure to move towards the side with lower pressure. However, the movement speed is relatively fast. The extension time within 100 mm is as short as 2 – 3 seconds. Even if the diameter of the piston damping hole is adjusted, the movement speed does not decrease significantly. This poses a greater safety hazard to operators and greatly reduces the consistency, stability, and service life of the product.

Summary of the Invention

In view of this, the present invention provides a threaded groove damping device, which can at least solve one of the above – mentioned problems. Through the threaded damping groove arranged circumferentially around the piston body, the movement of the piston assembly is made smooth, ensuring the smooth spring – back speed of the damping device. The design concept is ingenious, and at the same time, the safety and service life are improved.
To achieve the above – mentioned objectives, the present invention provides the following technical solutions: A threaded groove damping device includes a piston assembly and a closed cavity. There is a gap between the piston assembly and the closed cavity, and the piston assembly reciprocates in the closed cavity. A sealing member is arranged in the closed cavity, and the sealing member is used to seal the gap between the piston assembly and the closed cavity. The piston assembly includes a piston body and a piston sleeve closely sleeved on the piston body. A damping structure and a first flow – through hole are provided on the piston body. The damping structure is a threaded damping groove, which is arranged circumferentially around the piston body. A second flow – through hole is provided on the piston sleeve, and the second flow – through hole is in communication with both the threaded damping groove on the piston body and the first flow – through hole.

In some preferred embodiments, the threaded damping groove is a threaded slot, and the threaded damping groove is provided at both ends of the piston body or at one end of the piston body.

In some preferred embodiments, the second flow – through hole includes a side – surface flow – through hole and an end – surface communication hole, and the end – surface communication hole is adapted to the first flow – through hole.

In some preferred embodiments, one end of the threaded damping groove is connected to the side – surface flow – through hole, and the other end is connected to the end – surface communication hole, and the end – surface communication hole is connected to the first communication hole.

In some preferred embodiments, the threaded damping groove is provided on the side surface of the piston body.

In some preferred embodiments, the top of the groove of the threaded damping groove is in close contact with the inner surface of the piston sleeve.

In some preferred embodiments, a first protrusion and a second protrusion are provided on the piston body, and a groove is formed between the first protrusion and the second protrusion.

In some preferred embodiments, the sealing member moves within the groove. The axial width of the groove is greater than the maximum diameter of the cross – section of the sealing member. The sealing member is located above the first flow – through hole to ensure that the groove is in communication with the first flow – through hole.

In some preferred embodiments, the first flow – through hole includes a first left flow – through hole and a first right flow – through hole.

In some preferred embodiments, the first left flow – through hole is provided on the first protrusion, and the first right flow – through hole is provided on the second protrusion.

Features and advantages of the present invention: When the piston assembly moves under the extrusion of gas or oil pressure in the closed cavity, the sealing member provided in the closed cavity forms a frictional displacement with the inner wall of the closed cavity. The gas or oil pressure makes the sealing member tightly seal the gap between the piston assembly and the closed cavity, causing the gas to pass through the first flow – through hole, the circumferential damping structure and the second flow – through hole. Since the damping structure is arranged circumferentially around the piston body, the damping stroke for the gas or oil pressure is effectively extended, making the movement of the piston assembly smooth, ensuring the smooth spring – back speed of the damping device. The design concept is ingenious. At the same time, the safety and service life are greatly improved, thus solving the problems that the traditional gas spring has a fast movement speed and cannot effectively ensure its safety and service life.

Description of the Drawings

The following drawings are provided to further understand this application and form a part of this application. They are only intended to provide a schematic explanation and description of the present invention, and are not intended to limit the scope of the present invention. In the drawings:

• Fig. 1 is a schematic diagram of the assembly structure of a threaded groove damping device in Embodiment 1 of this application.
• Fig. 2 is a gas – flow diagram of the double – damping – structure piston assembly in the stretching movement in Embodiment 1 of this application.
• Fig. 3 is a gas – flow diagram of the double – damping – structure piston assembly in the compressing movement in Embodiment 1 of this application.
• Fig. 4 is a schematic diagram of the structure of the double – damping – structure piston body in Embodiment 1 of this application.
• Fig. 5 is a right – view of Fig. 4.
• Fig. 6 is a schematic sectional – view of the structure of the piston sleeve in Embodiment 1 of this application.
• Fig. 7 is a right – view of Fig. 6.
• Fig. 8 is a schematic diagram of the structure of the single – damping – structure piston body in Embodiment 2 of this application.
• Fig. 9 is a gas – flow diagram of the single – damping – structure piston assembly in the stretching movement in Embodiment 2 of this application.
• Fig. 10 is a gas – flow diagram of the single – damping – structure piston assembly in the compressing movement in Embodiment 2 of this application.

Reference numerals in the drawings:

• 2: Closed cavity
• 3: Sealing member
• 4: Rear connecting part
• 5: Front connecting part
• 11: Piston body
• 12: Piston sleeve
• 13: Piston rod
• 111: Threaded damping groove
• 112: First communication hole
• 114: Groove
• 115: First protrusion
• 116: Second protrusion
• 131: First baffle
• 132: Second baffle
• 121: Second communication hole
• 1121: First left communication hole
• 1122: First right communication hole
• 1211: End – surface flow – through hole
• 1212: Side – surface flow – through hole

Detailed Implementation Modes

The following will disclose multiple embodiments of this application through drawings. The technical solutions of the present invention will be described clearly and completely. The attached drawings, which form part of this application, are provided to further understand the present invention. The illustrative embodiments and descriptions of the present invention are used to explain the present invention and do not constitute improper limitations to the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

It should be noted that, unless the direction is defined separately, the directions such as up, down, left, right, inner, and outer involved in this text are based on the up, down, left, right, inner, and outer directions shown in Fig. 1 of the embodiment of this application. If the specific posture changes, the directional indication will change accordingly. The meanings of “multiple” and “several” are two or more, which are explained here together. The use of words such as “first”, “second”, “third” and the like does not indicate any order, quantity, or importance, but are only used to distinguish different components. In addition, in each embodiment of the present disclosure, the same or similar reference numerals represent the same or similar components.

In the present invention, unless otherwise clearly defined and limited, terms such as “connection” and “fixation” should be understood in a broad sense. For example, “fixation” can be a fixed connection, a detachable connection, or an integral one, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above – mentioned terms in the present invention can be understood according to specific situations.

In addition, the technical solutions among the various embodiments of the present invention can be combined with each other, but it must be based on what can be achieved by those of ordinary skill in the art. When the combination of technical solutions leads to contradictions or cannot be realized, it should be considered that such a combination of technical solutions does not exist and is not within the protection scope claimed by the present invention.

Embodiment 1

Please refer to Figs. 1 to 7. In this embodiment, for a threaded groove damping device, as shown in Fig. 1, the fixed end of the damping device is connected to the front connecting part 5, and the other movable end is connected to the rear connecting part 4. The damping device in this embodiment includes a piston assembly and a closed cavity 2. There is a gap between the piston assembly and the closed cavity 2, that is, they are in clearance fit, enabling the piston assembly to reciprocate in the closed cavity 2, dividing the closed cavity 2 into a left – hand closed cavity and a right – hand closed cavity 2. A sealing member 3 is arranged in the closed cavity 2. The sealing member 3 is used to seal the gap between the piston assembly and the closed cavity 2, so that the extruded gas cannot pass through the closed gap but flows to the threaded damping groove. The piston assembly includes a piston body 11, a piston sleeve 12 closely sleeved on the piston body 11, and a piston rod 13 for transmission. The piston body 11 and the piston sleeve 12 are fixed at one end of the piston rod by a first baffle 131, a second baffle 132, and a set nut. Specifically, a damping structure and a first flow – through hole 112 are provided on the piston body 11, and a second flow – through hole 121 is provided on the piston sleeve 12. The second flow – through hole 121 is in communication with both the damping structure on the piston body 11 and the first flow – through hole. It should be noted that the damping structure is arranged circumferentially around the piston body 11, which lengthens the damping stroke of the piston body 11 and makes the movement of the piston assembly more stable.
Using the technical solution of this embodiment, when the piston assembly moves under the extrusion of gas or oil pressure in the closed cavity 2, the sealing member 3 arranged in the closed cavity 2 forms a frictional displacement with the inner wall of the closed cavity 2. The gas or oil pressure makes the sealing member 3 tightly seal the gap between the piston assembly and the closed cavity 2, causing the gas to pass through the first flow – through hole, the circumferential threaded damping groove, and the second flow – through hole. Since the threaded damping groove is arranged circumferentially around the piston body, the damping stroke for the gas or oil pressure is effectively extended, making the movement of the piston assembly stable, ensuring the smooth spring – back speed of the damping device. The design concept is ingenious. At the same time, the safety and service life are greatly improved, thus solving the problems that the traditional gas spring has a fast movement speed and cannot effectively ensure its safety and service life.
As shown in Figs. 4 and 5, as a specific implementation mode, the threaded damping groove 111 in this embodiment is a threaded slot. The threaded damping groove 111 is arranged at both ends of the piston body 11, that is, the piston body 11 has a double – damping structure. This enables the piston assembly to be damped during both stretching and compressing movements, making the movement stable and improving safety and service life. Of course, according to actual situations, it can also be set as a one – way damping.
It should be noted that the thread profile of this threaded slot is preferably triangular. Of course, according to actual situations, it can also be trapezoidal, rectangular, or other irregular shapes. Furthermore, its groove depth (i.e., the setting parameters of the thread crest and root) and groove width (i.e., the setting parameter of the pitch) and the length of the threaded groove are set according to the actual requirements of damping.

As shown in Figs. 2 and 3, further, in this embodiment, the threaded damping groove 11 is arranged circumferentially on the side surface of the piston body 11. The groove top 1111 of the threaded damping groove 111 is in close contact with the inner surface 123 of the piston sleeve 12. The machining depth of the threaded damping groove 111 (i.e., the position of the groove bottom 1112) and its length are designed according to the actual damping strength and the required spring – back speed. It should be noted that the material of the piston body is preferably hard plastic, the piston sleeve is preferably made of copper or aluminum, and the groove top 1111 of the threaded damping groove 111 is preferably processed into a pointed shape. This is more conducive to ensuring a tighter contact between the threaded damping groove 111 and the inner wall 123 of the piston sleeve 12, thus better guaranteeing the sealing performance and enabling the flowing gas or liquid oil to flow along the path of the threaded damping groove 111.

As shown in Figs. 6 and 7, as a specific implementation mode, the second flow – through hole 121 on the piston sleeve 12 in this embodiment includes a side – surface flow – through hole 1211 and an end – surface communication hole 1212. As shown in Figs. 3 and 4, the end – surface communication hole 1212 is adapted to the first flow – through hole 112.

It should be noted that the end – surface communication hole 1212 in this embodiment is a circular blind hole, and the first flow – through hole 112 is a circular through – hole. However, their adaptation is not limited to circular holes, and they can be set as square holes, polygonal holes, or other special – shaped holes.

As shown in Figs. 4 and 5, as a specific implementation mode, a first protrusion 115 and a second protrusion 116 are provided on the piston body 11 in this embodiment. Both the first protrusion 115 and the second protrusion 116 are circumferential annular protrusions around the piston body, and a groove 114 is formed between them. Further, the first flow – through hole 112 in this embodiment includes a first left flow – through hole 1121 and a first right flow – through hole 1122. Furthermore, the first left flow – through hole 1121 and the first right flow – through hole 1122 are respectively provided on the first protrusion 115 and the second protrusion 116.

As shown in Figs. 2 and 3, as a specific implementation mode, one end of the threaded damping groove 111 in this embodiment is connected to the side – surface flow – through hole 1211, and the other end is connected to the end – surface communication hole 1212, which is connected to the first communication hole. Preferably, the sealing member 3 in this embodiment is arranged in the groove 114.

It should be noted that in this embodiment, the sealing member 3 is preferably a floating O – ring. The outer circle of the O – ring abuts against the inner wall of the closed cavity 2, and there is a certain distance between its inner circle and the bottom of the groove 114, allowing the gas flow to smoothly enter the first flow – through hole from the groove. This design can better utilize the principle of pressure to make the floating O – ring tightly abut against the inner wall of the closed cavity 2 and the side of the groove, thus achieving a better sealing effect. Moreover, it should be noted that the width of the groove 114 is greater than the maximum diameter of the cross – section of the sealing member 3, enabling the sealing member 3 to move within the groove and achieve the effect of sealing the gap on one side.

As shown in the gas – flow diagrams of the stretching and compressing movements in Figs. 2 and 3, the working principle of the two – way damping of this embodiment’s damping device with a double – damping structure when applied to a gas spring is described as follows:

1. Stretching Damping Movement: When performing a stretching movement to the right, first, the sealing member 3 in the closed cavity 2 is frictionally displaced to the left side of the groove 114. The gas pressure further prompts the sealing member 3 to tightly abut against the inner wall of the closed cavity 2 and the left side of the groove 114, sealing the left – hand gap between the closed cavity 2 and the piston assembly. Furthermore, the piston assembly squeezes the gas in the right – hand closed cavity, causing the gas to flow and be released into the left – hand closed cavity. At this time, only a small part of the gas flows into the right – hand threaded damping groove through the side – surface flow – through hole on the right – hand piston sleeve 12 and then enters the groove through the first right – hand flow – through hole 1122. Instead, the vast majority of the gas directly flows into the groove through the right – hand gap between the closed cavity 2 and the piston assembly. Then, it flows into the super – long left – hand threaded damping groove through the first left – hand flow – through hole 1121 and the end – surface flow – through hole on the left – hand piston sleeve 12. Finally, it flows into the left – hand closed cavity through the side – surface flow – through hole on the left – hand piston sleeve 12, thus completing a stable stretching damping movement.
2. Compressing Damping Movement: When performing a compressing movement to the left, first, the sealing member 3 in the closed cavity 2 is frictionally displaced to the right side of the groove 114. The gas pressure further prompts the sealing member 3 to tightly abut against the inner wall of the closed cavity 2 and the right side of the groove 114, sealing the right – hand gap between the closed cavity 2 and the piston assembly. Furthermore, the piston assembly squeezes the gas in the left – hand closed cavity, causing the gas to flow and be released into the right – hand closed cavity. At this time, only a small part of the gas flows into the left – hand threaded damping groove through the side – surface flow – through hole on the left – hand piston sleeve 12 and then enters the groove through the first left – hand flow – through hole. Instead, the vast majority of the gas directly flows into the groove through the left – hand gap between the closed cavity 2 and the piston assembly. Then, it flows into the super – long right – hand threaded damping groove through the first right – hand flow – through hole and the end – surface flow – through hole on the right – hand piston sleeve 12. Finally, it flows into the right – hand closed cavity through the side – surface flow – through hole on the right – hand piston sleeve 12, thus completing a stable compressing damping movement.

Embodiment 2

The difference between this embodiment and Embodiment 1 is that, as shown in Fig. 8, the threaded damping groove 111 in this embodiment is arranged at one end of the piston body 11, that is, the piston body has a single – damping structure.

As shown in the gas – flow diagrams of the stretching and compressing movements in Figs. 9 and 10, the working principle of this embodiment’s damping device with a single – damping structure when applied to a gas spring is described as follows:

1. Stretching Damping Movement: When performing a stretching movement to the right, first, the sealing member 3 in the closed cavity 2 is frictionally displaced to the left side of the groove 114. The gas pressure further prompts the sealing member 3 to tightly abut against the inner wall of the closed cavity 2 and the left side of the groove 114, sealing the left – hand gap between the closed cavity 2 and the piston assembly. Furthermore, the piston assembly squeezes the gas in the right – hand closed cavity, causing the gas to flow and be released into the left – hand closed cavity. At this time, the gas enters the groove through the first right – hand flow – through hole 1122 and/or the right – hand gap. Then, it flows into the super – long threaded damping groove through the first left – hand flow – through hole 1121 and the end – surface flow – through hole on the left – hand piston sleeve 12. Finally, it flows into the left – hand closed cavity through the side – surface flow – through hole on the piston sleeve 12, thus completing a stable stretching damping movement.
2. Compressing Damping Movement: When performing a compressing movement to the left, first, the sealing member 3 in the closed cavity 2 is frictionally displaced to the right side of the groove 114. The gas pressure further prompts the sealing member 3 to tightly abut against the inner wall of the closed cavity 2 and the right side of the groove 114, sealing the right – hand gap between the closed cavity 2 and the piston assembly. Furthermore, the piston assembly squeezes the gas in the left – hand closed cavity, and the entire gas is in a compressed state, causing the gas to flow and be released into the right – hand closed cavity. At this time, only a small part of the gas flows into the left – hand threaded damping groove through the side – surface flow – through hole on the left – hand piston sleeve 12 and then enters the groove through the first left – hand flow – through hole. Instead, the vast majority of the gas directly flows into the groove through the left – hand gap between the closed cavity 2 and the piston assembly. Then, it directly flows into the right – hand closed cavity only through the first right – hand flow – through hole, thus completing the compressing damping movement. This kind of compressing damping is the characteristic of an ordinary compressed gas spring that only uses the damping hole for damping.

In conclusion, when the piston assembly in this application moves under the extrusion of gas or oil pressure in the closed cavity, the sealing member arranged in the closed cavity forms a frictional displacement with the inner wall of the closed cavity. The gas or oil pressure makes the sealing member tightly seal the gap between the piston assembly and the closed cavity, causing the gas to pass through the first flow – through hole, the circumferential damping structure, and the second flow – through hole. Since this super – long damping structure is arranged circumferentially around the piston body, the damping stroke for the gas or oil pressure is effectively extended, making the movement of the piston assembly stable, ensuring the smooth spring – back speed of the damping device. The design concept is ingenious. At the same time, the safety and service life are greatly improved, thus solving the problems that the traditional gas spring has a fast movement speed and cannot effectively ensure its safety and service life.

The above description shows and describes the preferred embodiments of this application. However, as mentioned before, it should be understood that this application is not limited to the forms disclosed herein. It should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications, and environments, and can be changed within the scope of the concept of this application through the above teachings or the technologies or knowledge in related fields. Any changes and variations made by those skilled in the art without departing from the spirit and scope of this application shall fall within the protection scope of the appended claims of this application.

Claims (10)  – A Threaded Groove Damping Gas Spring, invented by LeiYan Gas Spring, a pioneer Chinese Gas Spring Manufacturer.

1. A threaded groove damping device, comprising a piston assembly and a closed cavity (2), characterized in that: a gap is provided between the piston assembly and the inner wall of the closed cavity (2), and the piston assembly reciprocates in the closed cavity;
   a sealing member (3) is provided in the closed cavity (2), and the sealing member (3) is used to seal the gap;
   the piston assembly comprises a piston body (11) and a piston sleeve (12) closely sleeved on the piston body (11). A damping structure and a first flow – through hole (112) are provided on the piston body (11). The damping structure is a threaded damping groove, which is arranged circumferentially around the piston body (11). A second flow – through hole (121) is provided on the piston sleeve (12), and the second flow – through hole (121) is in communication with both the threaded damping groove on the piston body (11) and the first flow – through hole (112).
2. The threaded groove damping device according to claim 1, characterized in that the threaded damping groove (111) is provided at both ends of the piston body (11) or at one end of the piston body (11).
3. The threaded groove damping device according to claim 1 or 2, characterized in that the second flow – through hole (121) comprises a side – surface flow – through hole (1212) and an end – surface communication hole (1211), and the end – surface communication hole (1211) is adapted to the first flow – through hole (112).
4. The threaded groove damping device according to claim 3, characterized in that one end of the threaded damping groove (111) is connected to the side – surface flow – through hole (1212), and the other end is connected to the end – surface communication hole (1211), and the end – surface communication hole (1211) is connected to the first communication hole (112).
5. The threaded groove damping device according to claim 2, characterized in that the threaded damping groove (111) is provided on the side surface of the piston body (11).
6. The threaded groove damping device according to claim 2, characterized in that the groove top (1111) of the threaded damping groove (111) is in close contact with the inner surface of the piston sleeve (12).
7. The threaded groove damping device according to claim 1, characterized in that a first protrusion (115) and a second protrusion (116) are provided on the piston body (11), and a groove (114) is formed between the first protrusion (115) and the second protrusion (116).
8. The threaded groove damping device according to claim 7, characterized in that the sealing member (3) moves in the groove (114).
9. The threaded groove damping device according to claim 1 or 7, characterized in that the first flow – through hole (112) comprises a first left flow – through hole (1121) and a first right flow – through hole (1122).
10. The threaded groove damping device according to claim 9, characterized in that the first left flow – through hole (1121) is provided on the first protrusion (115), and the first right flow – through hole is provided on the second protrusion (116).