A protection device for preventing telescopic oil cylinder instability

Abstract

The application provides a protection device for preventing telescopic oil cylinder from losing stability, and belongs to the technical field of engineering machinery. The technical scheme is as follows: a protection device for preventing telescopic oil cylinder from losing stability, comprising multiple anti-instability devices slidably arranged on a two-section arm, a guide seat arranged on a one-section arm, a telescopic oil cylinder connected between the one-section arm and the lower side of the two-section arm, a cylinder rod of the telescopic oil cylinder sliding through the lower side of the multiple anti-instability devices, and a guide hole arranged on each anti-instability device, wherein the size of the guide hole gradually decreases from the tail of the two-section arm to the head of the two-section arm. The application has the beneficial effects that the multiple anti-instability devices arranged on the cylinder rod of the telescopic oil cylinder effectively reduce the instability risk of the cylinder rod when the cylinder rod is too long and the disturbance in the movement process.

Description

Technical Field

[0001] This invention relates to the field of engineering machinery technology, and in particular to a protective device for preventing instability of telescopic hydraulic cylinders. Background Technology

[0002] Aerial work platforms, as specialized vehicles for carrying people to perform high-altitude operations, are increasingly replacing the previously highly dangerous climbing work methods. With the development of urban construction, aerial work platforms are not only used in large-scale infrastructure projects such as docks, airports, water conservancy, power stations, and landscaping, but are also widely used in the installation and management of urban facilities such as streetlights, communications, transportation, advertising, and photography.

[0003] Because aerial work platforms are work devices that carry people into the air, and the boom is the most important component of an aerial work platform, multi-stage telescopic booms typically consist of a single telescopic cylinder that drives a multi-stage wire rope system or a plate chain pulley system to achieve the telescopic movement of the multi-stage boom. One common telescopic cylinder layout involves the cylinder barrel being mounted on the first boom section via a flange or hinge, and the cylinder rod being mounted on the boom head of the second boom section via a flange or hinge. Driven by the telescopic cylinder, the second boom section telescopically moves relative to the first boom section. Current technical problems include:

[0004] Due to factors such as space and weight, the diameter of the telescopic cylinder cannot be too large. If the boom is very long, the telescopic cylinder needs to be lengthened accordingly. Under normal circumstances, the load-bearing capacity of the telescopic cylinder meets the requirements, but due to the influence of the pressure rod stability, the cylinder rod is at risk of instability under a certain load and at a certain length. Moreover, during the telescopic cylinder's extension and retraction, the vibration of the cylinder rod can cause instability in the boom system. The usual solutions are to thicken the cylinder rod, shorten the stroke of the entire telescopic cylinder, or reduce the load. However, thickening the cylinder rod, shortening the stroke of the entire telescopic cylinder, or reducing the load all increase the self-weight of the system and sacrifice performance, and cannot completely solve the disturbance and instability risks caused by excessively long cylinders.

[0005] Therefore, there is an urgent need for a protective device to prevent the telescopic cylinder from becoming unstable in order to solve the above technical problems. Summary of the Invention

[0006] The purpose of this invention is to provide a protective device to prevent the instability of a telescopic cylinder. This protective device can effectively solve the risk of cylinder rod instability without thickening the cylinder rod, shortening the stroke of the entire telescopic cylinder, or reducing the load. It can also reduce the instability of the boom system caused by lever disturbance during the entire movement of the telescopic cylinder.

[0007] To achieve the aforementioned objectives, the present invention employs the following technical solution: a protective device for preventing the instability of a telescopic hydraulic cylinder, comprising multiple anti-instability devices slidably sleeved on a second-section arm, and a guide seat disposed on a first-section arm. A telescopic hydraulic cylinder is connected between the lower sides of the first and second sections of the arm. The cylinder rod of the telescopic hydraulic cylinder slides through the lower sides of the multiple anti-instability devices. Each anti-instability device is provided with a guide hole. The size of the guide hole gradually decreases from the tail end to the head end of the second-section arm. A guide rod is fixedly disposed at the head end of the second-section arm, and the other end of the guide rod passes through the multiple guide seats. The guide rod rests on the upper surface of the guide seat after the hole is opened. Multiple magnetic rings corresponding to the guide holes are equidistantly arranged on the upper side of the guide rod. The size of the magnetic ring is larger than the size of the corresponding guide hole and smaller than the size of the guide hole adjacent to the corresponding guide hole and located in the direction of the tail of the second arm. A retraction sleeve is provided on the guide rod between the anti-instability device and the head of the second arm. The size of the retraction sleeve is larger than the size of the guide hole adjacent to it. A limit frame is also provided on the first arm. The anti-instability device is provided with a limit hole for the limit frame to pass through. The limit frame is provided with a snap-fit ​​component corresponding to the multiple limit holes.

[0008] Furthermore, the locking component consists of multiple bosses on the limiting frame. From the tail of the arm to the head of the arm, the size of the multiple bosses decreases sequentially. The size of each limiting hole is smaller than the size of its corresponding boss and larger than the size of the boss adjacent to the corresponding boss and located in the head direction of the arm. In this way, during the retraction of the two-section arm, the guide hole on the anti-instability device can pass through the corresponding boss, so that the anti-instability device as a whole returns to its position on the limiting frame.

[0009] Furthermore, the boss has an arc structure, which facilitates the formation of a groove to engage with the limiting hole.

[0010] Furthermore, each of the anti-instability devices is provided with a limit block on the side near the arm tail, and the anti-instability device closest to the arm tail of the second section is not provided with a limit block. During the retraction of the second section arm, the limit block can limit the distance between adjacent anti-instability devices, so that all anti-instability devices return to the limit frame as a whole.

[0011] Furthermore, the limiting frame is an elastic component. This design allows the anti-instability device to overcome the friction between the limiting hole and the corresponding boss during the extension or retraction of the two-section arm, and continue to move.

[0012] Furthermore, the upper surface of the guide seat is provided with a guide groove, and the guide rod is located in the guide groove. The guide groove can limit the movement of the guide rod to a certain extent, so that the movement of the guide rod is stable.

[0013] Furthermore, the magnetic ring has a sector-shaped plate structure, which has a large contact area with the anti-limiting component, making it more stable when pushing the anti-limiting component to move.

[0014] Furthermore, the magnetic ring is located above the guide seat, which prevents the guide rod from interfering with the guide seat during retraction.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0016] 1. This invention can reduce the risk of instability and disturbance during movement when the cylinder rod is too long. By utilizing the different sizes of the guide rod, magnetic ring and guide hole, the corresponding hydraulic cylinder protection device can reach the corresponding position during the extension of the two-section arm. At this time, multiple anti-instability devices will support the cylinder rod of the telescopic hydraulic cylinder at the same time, thereby greatly increasing the critical force of the pressure rod and improving the stability of the cylinder rod.

[0017] 2. By using guide rods, retraction sleeves, and limit brackets, the protection device of the hydraulic cylinder is retracted to the corresponding position, reducing the size of the entire protection device and saving space. At the same time, multiple anti-instability devices are close together and neatly positioned on the limit bracket. The protrusions on the limit bracket will lock and fix the anti-instability devices, resulting in good storage effect and high safety.

[0018] 3. When the boom is at a negative elevation angle, the magnetic ring has a certain magnetic attraction force, which can prevent the anti-instability device from sliding towards the boom head under the action of gravity and thus losing its function, greatly improving the safety performance of the telescopic boom.

[0019] 4. The protective device has a reasonable structure and ingenious design. Without thickening the cylinder rod, shortening the stroke of the entire telescopic cylinder, or reducing the load, multiple anti-instability devices can provide reasonable and even support for the cylinder rod, and play a role in protecting the telescopic cylinder rod from instability and preventing vibration. Attached Figure Description

[0020] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof.

[0021] Figure 1 This is a three-dimensional structural diagram of the present invention.

[0022] Figure 2 This is a schematic diagram of the structure of the present invention in its retracted state.

[0023] Figure 3 This is a schematic diagram of the limiting frame in this invention.

[0024] Figure 4 This is a schematic diagram of the structure of an embodiment of the present invention.

[0025] The attached figures are labeled as follows:

[0026] 1. Two-section arm;

[0027] 2. Anti-instability device; 21. Anti-instability device one; 22. Anti-instability device two; 23. Anti-instability device three;

[0028] 3. One arm segment;

[0029] 4. Guide seat;

[0030] 5. Telescopic hydraulic cylinder;

[0031] 6. Guide hole; 61. Guide hole one; 62. Guide hole two; 63. Guide hole three;

[0032] 7. Guide rod;

[0033] 8. Magnetic ring; 81. Magnetic ring one; 82. Magnetic ring two; 83. Magnetic ring three;

[0034] 9. Retraction sleeve;

[0035] 10. Limiting bracket;

[0036] 11. Limiting hole; 111. Limiting hole one; 112. Limiting hole two; 113. Limiting hole three;

[0037] 12. Boss; 121. Boss 1; 122. Boss 2; 123. Boss 3;

[0038] 13. Limiting block; 131. Limiting block one; 132. Limiting block two;

[0039] 14. Fixing plate. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. Of course, the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0041] Example:

[0042] This embodiment provides a protective device to prevent the instability of a telescopic hydraulic cylinder, and the following description uses three sets of anti-instability devices as an example.

[0043] like Figure 1-4 The protective device includes the following components: a first arm 3, a second arm 1, an anti-instability device 1 21, an anti-instability device 22, an anti-instability device 3 23, a guide seat 4, a telescopic cylinder 5, a guide hole 1 61, a guide hole 2 62, a guide hole 3 63, a guide rod 7, a magnetic ring 1 81, a magnetic ring 2 82, a magnetic ring 3 83, a retraction sleeve 9, a limit frame 10, a limit hole 111, a limit hole 112, a limit hole 113, a boss 121, a boss 2 122, a boss 3 123, a limit block 131, and a limit block 2 132.

[0044] The guide rod 7 is fixed at one end on the upper part of the second-section arm 1, and the guide seat 4 is fixed on the upper part of the first-section arm 3. The guide rod 7 can move relative to the first-section arm 3 along with the second-section arm 1. Magnetic rings 81, 82, and 83 are magnetic rings and are fixed at a certain interval on the upper side of the guide rod 7. The retraction sleeve 9 is installed on the head of the guide rod 7 and can move with the guide rod 7. The guide seat 4 supports and guides the guide rod 7. The anti-instability devices 21, 22, and 23 are mainly installed on the second-section arm 1 and can slide relative to the second-section arm 1. The lower side of the anti-instability device 2 has a guide sleeve, which is installed on the cylinder rod of the telescopic cylinder 5 and can slide relative to the cylinder rod. The anti-instability devices 21, 22, and 23 can ensure the stability of the distance between the cylinder rod and the second-section arm 1 and can also prevent the cylinder rod from being disturbed during movement, thereby effectively preventing the cylinder rod from becoming unstable.

[0045] The size relationships are as follows: guide rod 7 < guide hole 3 63 < magnetic ring 3 83 < guide hole 2 62 < magnetic ring 2 82 < guide hole 1 61 < magnetic ring 1 81, guide hole 3 63 < retraction sleeve 9.

[0046] The limiting frame 10 is a support with a certain degree of elasticity and containing three semi-circular bosses. In the retracted state of the boom, the anti-instability device 1 21, the anti-instability device 22, and the anti-instability device 3 23 are temporarily fixed in the groove between the bosses 121, 122, and 123 through the limiting holes 111, 112, and 113. The size relationship is as follows: limiting hole 3 113 < boss 3 123 < limiting hole 2 112 < boss 2 122 < limiting hole 1 111 < boss 1 121. The size of boss 3 123 is slightly larger than that of limiting hole 3 113, the size of boss 2 122 is slightly larger than that of limiting hole 2 12, and the size of boss 1 121 is slightly larger than that of limiting hole 1 111. The anti-instability device 2 22 is provided with a limiting block 1 131, and the anti-instability device 3 23 is provided with a limiting block 2 132.

[0047] The specific working principle is as follows:

[0048] When the cylinder rod of the telescopic cylinder 5 extends, it drives the second-section arm 1 to extend outward relative to the first-section arm 3. The second-section arm 1 drives the guide rod 7 to extend outward together. At this time, the magnetic ring 83 first passes through the guide hole 61 and the guide hole 62, and then contacts the anti-instability device 23 and pushes the anti-instability device 23 to the right. Since the limit frame 10 is an elastic plate and the size of the limit hole 113 is slightly smaller than the boss 123, the limit hole 113 can overcome the friction between itself and the boss 123 under the push of the magnetic ring 83, causing the anti-instability device 23 to move to the right. The same principle applies as the second-section arm 1... As the cylinder continues to extend, under the respective pushing of magnetic ring 82 and magnetic ring 81, the limiting hole 112 can overcome the friction between itself and boss 122, and the limiting hole 111 can overcome the friction between itself and boss 121, causing the anti-instability device 22 and anti-instability device 21 to move to the right. After the second arm 1 extends into place, since the three magnetic rings 8 are equidistantly arranged, the anti-instability device 21, anti-instability device 22, and anti-instability device 23 are also equidistantly distributed on the cylinder rod and jointly support the cylinder rod. Therefore, the cylinder can be more stable when it is working and there will be no shaking.

[0049] When the telescopic cylinder 5 retracts the second section arm 1, the retraction sleeve 9 retracts along with the guide rod 7. When the retraction sleeve 9 contacts the anti-instability device 23, it retracts along with the anti-instability device 23. When the limit block 132 on the anti-instability device 23 contacts the anti-instability device 22, it retracts along with the anti-instability device 22. When the limit block 131 on the anti-instability device 22 contacts the anti-instability device 21, it retracts along with the anti-instability device 21. Thus, the anti-instability devices 21, 22, and 323 retract together and simultaneously. Since the limit hole 113 < boss 123 < limit hole... Therefore, anti-instability device 121 can pass over boss 3 123 and boss 2 122. Simultaneously, under the action of a certain elastic force from the limiting bracket 10, the limiting hole 111 can overcome the frictional force between itself and boss 121, causing anti-instability device 121 to fall into the groove on the left side of boss 121. Similarly, anti-instability device 22 can pass over boss 2 122, and under the action of a certain elastic force, overcome the frictional force to fall into the groove on the left side of boss 2 122. Anti-instability device 3 23, under the action of a certain elastic force, overcomes the frictional force to fall into the groove on the left side of boss 3 123, and eventually retracts to... Figure 2 The location shown.

[0050] This article uses three sets of anti-instability devices as examples to explain the principle. Assuming the lever stroke of the telescopic cylinder 5 is L, we know that the critical force calculation formula for the pressure rod is: Fcr=π2EI / (μl)2, where μ is the length coefficient, E is the elastic modulus, I is the moment of inertia, and l is the length of the pressure rod. Under the condition that the cylinder rod diameter and fixing method are fixed, I and μ are constant values, and Fcr is related to l. When there is no instability protection device, we can assume that l=L. In this case, if we add one set of anti-instability protection device, we can consider l=1 / 2*L. At this time, the critical force of the pressure rod Fcr'=4*Fcr. If we add n sets of anti-instability protection devices at equal intervals, we can consider l=1 / n*L. At this time, the critical force of the pressure rod Fcr'=n2*Fcr. It can be seen that the anti-instability device 2 can significantly increase the critical force of the pressure rod, thereby improving the stability of the lever.

[0051] In addition, this device has another advantage: when the boom is at a negative elevation angle, since magnetic ring 1 81, magnetic ring 2 82 and magnetic ring 3 83 are magnetic attraction rings with a certain magnetic attraction force, it can prevent the anti-instability device 1 21, anti-instability device 22 and anti-instability device 3 23 from sliding towards the boom head under the action of gravity and thus losing their function.

[0052] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A protective device for preventing instability of a telescopic hydraulic cylinder, characterized in that, The device includes multiple anti-instability devices (2) that are slidably mounted on the second arm (1) and a guide seat (4) set on the first arm (3). The cylinder rod of the telescopic cylinder (5) slides through the fixing holes on the fixing plate (14) on the lower side of the multiple anti-instability devices (2). Each anti-instability device (2) is provided with a guide hole (6). From the arm tail to the arm head of the second arm (1), the size of the multiple guide holes (6) gradually decreases. The arm head of the second arm (1) is connected to a guide rod (7). The other end of the guide rod (7) passes through the multiple guide holes (6) and rests on the upper surface of the guide seat (4). Multiple magnetic rings (8) corresponding to the guide holes (6) are equidistantly arranged on the upper side of the guide rod (7). The size of the magnetic ring (8) is larger than the size of the corresponding guide hole (6) and smaller than the size of the guide hole (6) adjacent to the corresponding guide hole (6) and located in the arm tail direction of the second arm (1).

2. The protective device for preventing instability of a telescopic hydraulic cylinder according to claim 1, characterized in that, The arm section (3) is provided with a limit frame (10), the anti-instability device (2) is provided with a limit hole (11) for the limit frame (10) to pass through, and the limit frame (10) is provided with a snap-fit ​​component corresponding to the multiple limit holes (11).

3. The protective device for preventing instability of a telescopic hydraulic cylinder according to claim 2, characterized in that, The snap-fit ​​component consists of multiple bosses (12) on the limiting frame (10), with the size of the multiple bosses (12) decreasing sequentially from the tail of the arm to the head of the arm.

4. The protective device for preventing instability of a telescopic hydraulic cylinder according to claim 3, characterized in that, Each of the limiting holes (11) is smaller than the size of its corresponding boss (12) and larger than the size of the boss (12) adjacent to the corresponding boss (12) and located in the arm head direction.

5. The protective device for preventing instability of a telescopic hydraulic cylinder according to claim 4, characterized in that, The limiting frame (10) is an elastic component, and the top of the boss (12) is an arc structure.

6. The protective device for preventing instability of a telescopic hydraulic cylinder according to claim 1, characterized in that, A retraction sleeve (9) is provided on the guide rod (7) located between the anti-instability device (2) and the arm head of the two-section arm (1). The size of the retraction sleeve (9) is larger than the size of the guide hole (6) adjacent to it.

7. The protective device for preventing instability of a telescopic hydraulic cylinder according to claim 1, characterized in that, The anti-instability device (2) is provided with a limit block (13) on the side near the arm tail, and the anti-instability device (2) closest to the arm tail of the two-section arm (1) is not provided with a limit block.

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