Self-circulation variable-speed three-cylinder structure

Abstract

The invention relates to a self-circulation variable-speed three-cylinder structure, the three-cylinder structure comprises a barrel, a sealed cylinder body arranged in the barrel, a large plunger and a small plunger, the large plunger is T-shaped, the large plunger comprises a piston rod and a piston, the piston divides the cylinder body into an oil inlet area and an oil return area which are not communicated with each other, the piston rod is located in the oil inlet area, and the small plunger is located in the oil return area. The front end of the piston rod penetrates through the cylinder body and the front end of the barrel and acts outwards; the interior of the large plunger is hollow, the small plunger penetrates through the cylinder body and the rear end of the cylinder body and is fixed to the cylinder body and the rear end of the cylinder body, the front end of the small plunger is inserted into the hollow area of the large plunger, the hollow area of the large plunger is partitioned by the front end of the small plunger, and the small plunger is provided with a second oil inlet and is communicated with the hollow area of the large plunger; the oil inlet area is provided with a first oil inlet. Different hydraulic cylinders can be formed by selecting different oil inlets, different driving rates can be obtained on the basis that the flow of hydraulic oil is not changed, and the application range is wider.

Description

Technical Field

[0001] The invention relates to the technical field of hydraulic cylinders, and in particular to a self-circulating speed-changing three-cylinder structure. Background Art

[0002] Hydraulic cylinders are important driving components in modern industry. They are hydraulic actuators that convert hydraulic energy into mechanical energy and perform linear reciprocating motion (or swinging motion). The driving speed of existing hydraulic cylinders often depends on the rate at which hydraulic oil enters the cylinder body. Although the purpose of speed regulation can be achieved, it can generally only be adjusted within a small range and cannot meet actual needs. Therefore, the field needs a hydraulic cylinder that can adjust the driving speed to a large extent. Summary of the invention

[0003] The purpose of the present invention is to provide a self-circulating speed-changing three-cylinder structure in order to overcome the defects of the above-mentioned prior art.

[0004] In order to achieve the purpose of the present invention, this application provides the following technical solutions.

[0005] In the first aspect, the present application provides a self-circulating speed-changing three-cylinder structure, characterized in that the three-cylinder structure includes a barrel, a cylinder body arranged inside the barrel and sealed, a large plunger arranged inside the cylinder body, and a small plunger arranged inside the large plunger, wherein the large plunger is T-shaped, and the large plunger includes a piston rod and a piston, the piston divides the cylinder body into an oil inlet area and an oil return area that are not connected to each other, the piston rod is located in the oil return area, and the front end of the piston rod penetrates the front end of the cylinder body and the barrel body and performs work externally; the interior of the large plunger is hollow, and the small plunger penetrates the rear ends of the barrel and the cylinder body and is fixed to the rear ends of the barrel and the cylinder body, the front end of the small plunger is inserted into the hollow area of ​​the large plunger, and the front end of the small plunger separates the hollow area of ​​the large plunger, the small plunger is provided with a second oil inlet and is connected to the hollow area of ​​the large plunger, and the oil inlet area is provided with a first oil inlet. In this application, oil can be fed from the first oil inlet alone, the second oil inlet alone, or both. All three methods can push the front end of the large plunger forward to perform work. Moreover, by injecting the same flow of hydraulic oil, different driving speeds can be generated by adjusting the oil feed ratio between the first oil inlet and the second oil inlet, thereby increasing the scope of application.

[0006] In an implementation manner of the first aspect, a filling liquid is filled between the outer wall of the cylinder body and the inner wall of the barrel body, and a liquid replenishing port is provided on the barrel body.

[0007] In an implementation of the first aspect, a first oil passage is provided between the cylinder and the oil inlet area, and a first check valve is provided on the first oil passage, and the first check valve allows the filling liquid to enter the oil inlet area.

[0008] In one embodiment of the first aspect, a second oil passage is provided between the cylinder and the second oil inlet, and a second check valve is provided on the second oil passage, and the second check valve allows the filling liquid to enter the second oil inlet. The first oil passage, the second oil passage and the filling liquid are provided to avoid the formation of a vacuum in the oil inlet area and the hollow area of ​​the large plunger, which affects the advancement of the large plunger.

[0009] In one implementation of the first aspect, a sealing ring is provided at the front end of the small plunger, and the sealing ring matches the inner diameter of the large plunger.

[0010] In one implementation of the first aspect, the oil return area is provided with an oil return port. The purpose of providing the oil return port is to drive the large plunger to retreat.

[0011] In an implementation manner of the first aspect, the first oil inlet and the second oil inlet are connected to the same hydraulic oil source.

[0012] Compared with the prior art, the present invention has the following beneficial effects:

[0013] The present application can form different hydraulic cylinders by selecting different oil inlets, and can obtain different driving speeds without changing the flow rate of the hydraulic oil, thus having a wider range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a schematic diagram of the self-circulating speed-changing three-cylinder structure of the present application.

[0015] In the accompanying drawings, 1 is a barrel, 2 is a cylinder body, 3 is a large plunger, 4 is a small plunger, 5 is a first oil inlet, 6 is a second oil inlet, 7 is an oil return port, 8 is a liquid replenishing port, 9 is a filling area, 10 is a first oil passage, 11 is a first check valve, 12 is a second oil passage, 13 is a second check valve, 14 is an oil inlet area, 15 is an oil return area, 16 is a hollow area, 17 is a piston rod, 18 is a piston, 19 is an oil storage tank, 20 is a first hydraulic valve, 21 is a second hydraulic valve, 22 is an oil return tank, and 23 is an oil pump. DETAILED DESCRIPTION

[0016] Unless otherwise defined, the technical or scientific terms used in this specification and claims shall have the ordinary meanings understood by persons having ordinary skills in the technical field to which the present invention belongs. All the values ​​from the lowest value to the highest value listed herein refer to all the values ​​obtained by incrementing one unit between the lowest value and the highest value when the difference between the lowest value and the highest value is more than two units.

[0017] The specific embodiments of the present invention will be described below. It should be noted that in the specific description of these embodiments, for the sake of concise description, it is impossible for this specification to describe all the features of the actual embodiments in detail. Without departing from the spirit and scope of the present invention, those skilled in the art may modify and replace the embodiments of the present invention, and the resulting embodiments are also within the scope of protection of the present invention.

[0018] Example

[0019] The embodiments of the present invention will be described in detail below. This embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation method and a specific operation process are given, but the protection scope of the present invention is not limited to the following embodiments.

[0020] Example 1

[0021] A self-circulating speed-changing three-cylinder structure, the structure of which is as follows Figure 1 As shown, it includes a barrel 1, a cylinder 2 is coaxially arranged inside the barrel 1, and the front and rear ends of the cylinder 2 are respectively fixed and sealed to the inner walls of the front end face and the rear end face of the barrel 1. There is a filling area 9 between the barrel 1 and the cylinder 2, and the filling area 9 is filled with filling liquid. A liquid replenishing port 8 is arranged on the side wall of the barrel 1 for replenishing the filling liquid. A T-shaped large plunger 3 is arranged inside the cylinder 2, and the large plunger 3 includes a piston rod 17 and a piston 18. The piston 18 divides the inside of the cylinder 2 into an oil inlet area 14 and an oil return area 15 that are not connected to each other. The piston rod 17 is located in the oil return area 15. The oil return area 15 of the cylinder 2 is provided with an oil return port 7, and the oil inlet area 14 is provided with a first oil inlet port 5. The front end of the piston rod 17 penetrates the front end face of the barrel 1. During manufacturing, it is necessary to ensure that there is no oil leakage at the contact between the piston rod 17 and the front end face of the barrel 1. A hollow area 16 is arranged inside the piston rod 17, and the front end of the piston rod 17 is sealed and the rear end is open. The three-cylinder structure is also provided with a small plunger 4, which penetrates the rear end face of the cylinder 1 and is inserted into the hollow area 16 of the piston rod 17 from the rear end opening of the piston rod 17. A channel that passes through the front and back is provided in the small plunger 4, the front end of which is connected to the hollow area 16, and the rear end of which is connected to the second oil inlet 6. The outer wall of the small plunger 4 is fixed and sealed to the rear end face of the cylinder 1. A first oil passage 10 is provided between the space between the cylinder 1 and the cylinder 2 and the oil inlet area 14, and a first check valve 11 is provided on the first oil passage 10, and the first check valve 11 allows the filling liquid to enter the oil inlet area 14 in one direction. At the same time, a second oil passage 12 is provided between the space between the cylinder 1 and the cylinder 2 and the second oil inlet 6, and a second check valve 13 is provided on the second oil passage 12, and the second check valve 13 allows the filling liquid to enter the second oil inlet 6 in one direction. In this embodiment, the first oil inlet 5 and the second oil inlet 6 are connected to the same hydraulic oil source (only a three-way valve is used as an example in the figure).

[0022] The working principle of the above structure is as follows.

[0023] (1) When the first oil inlet 5 and the second oil inlet 6 are simultaneously supplied with oil (the first hydraulic valve 20 and the second hydraulic valve 21 are both connected to the left half of the oil circuit), due to the presence of the oil pump 23, part of the hydraulic oil in the liquid storage tank 19 enters the oil inlet area 14 through the first oil inlet 5, pushing the piston 18 forward, thereby driving the piston rod 17 forward; the remaining part of the hydraulic oil enters the hollow area 16 through the second oil inlet 6, pushing the piston rod 17 forward, that is, the two work together to push the large plunger 3 forward to do work. At this time, due to the forward movement of the piston 18, the volume of the oil return area 15 becomes smaller and smaller, and the hydraulic oil in the oil return area 15 flows back to the oil return tank 22 through the oil return port 7.

[0024] (2) When the first oil inlet 5 is filled with oil and the second oil inlet 6 is closed (the first hydraulic valve 20 connects the left half of the oil circuit, and the second hydraulic valve 21 remains in a blocked state), the hydraulic oil can only enter the oil inlet area 14 through the first oil inlet 5 under the action of the oil pump 23, pushing the piston 18 forward and driving the piston rod 17 forward. However, since the small plunger 4 is fixed, the forward movement of the piston rod 17 increases the volume of the hollow area 16, generating negative pressure. At this time, the filling liquid in the filling area 9 will enter the second oil inlet 6 through the second oil passage 12 and fill into the hollow area 16 to compensate for the negative pressure. In order to ensure that the filling oil in the filling area 9 is sufficient, the return oil tank 22 can replenish the filling liquid into the filling area 9 through the liquid replenishment port 8. In addition, as the piston 18 moves forward, the volume of the return oil area 15 becomes smaller and smaller, and the hydraulic oil in the return oil area 15 flows back to the return oil tank 22 through the return oil port 7 and the first hydraulic valve 20.

[0025] (3) When the first oil inlet 5 is closed and the second oil inlet 6 is opened (the first hydraulic valve 20 remains in a blocked state, and the second hydraulic valve 21 connects the left half of the oil circuit), the hydraulic oil can only enter the hollow area 16 through the second oil inlet 6 under the action of the oil pump 23, directly pushing the piston rod 17 forward and driving the piston 18 forward at the same time. In this way, a negative pressure will be generated in the oil inlet area 14. At this time, the filling liquid in the filling area 9 will enter the oil inlet area 14 through the first oil passage 10 to compensate for the negative pressure. In order to ensure that there is sufficient filling oil in the filling area 9, the return oil tank 22 can replenish the filling liquid into the filling area 9 through the liquid replenishment port 8. In addition, as the piston 18 moves forward, the volume of the return oil area 15 becomes smaller and smaller, and the hydraulic oil in the return oil area 15 flows back to the liquid storage tank 19 through the return oil port 7 and the second hydraulic valve 21.

[0026] (4) When the work is finished, the first oil inlet 5 and the second oil inlet 6 remain open (the first hydraulic valve 20 and the second hydraulic valve 21 are both connected to the right half of the oil circuit), and the return oil tank 22 injects hydraulic oil into the return oil area 15 through the return oil port 7. The hydraulic oil pushes the piston 18 to move backward. At this time, the hydraulic oil originally located in the oil inlet area 14 flows out through the first oil inlet 5 and returns to the liquid storage tank 19, and the hydraulic oil located in the hollow area 16 flows out through the second oil inlet 6 and returns to the liquid storage tank 19.

[0027] Next, we will use data to explain the reasons for the different driving speeds of the three-cylinder structure. For ease of understanding, the numerical values ​​described below are for illustration only and are not necessarily real data.

[0028] Assuming that the total oil inlet flow rate remains constant at 90L / min (i.e., the total oil inlet flow rate of the first oil inlet 5 and the second oil inlet 6 is 100L / min), the inner diameter of the hollow area 16 is r, and the inner diameter of the cylinder body 2 is 3r, that is, the cross-sectional area of ​​the hollow area 16 and the cross-sectional area of ​​the cylinder body 2 are A:9A. When the first oil inlet 5 and the second oil inlet 6 are simultaneously supplied with oil, the oil inlet flow rate of the first oil inlet 5 is 80L / min, and the oil inlet flow rate of the second oil inlet 6 is 10L / min. At this time, the forward speed of the large plunger 3 is 1m / min.

[0029] When the second oil inlet 6 is closed, all 90L / min of hydraulic oil enters the oil inlet area 14 through the first liquid inlet and acts on the piston 18, that is, 90L / min of hydraulic oil acts on the cross-sectional area of ​​8A, which will produce a forward speed of 1.25m / min.

[0030] When the first oil inlet 5 is closed, all 90L / min of hydraulic oil enters the hollow area 16 through the second oil inlet and acts on the front end of the piston rod 17, that is, 90L / min of hydraulic oil acts on the cross-sectional area of ​​A, which will produce a forward speed of 9m / min.

[0031] In this way, different driving speeds can be obtained by switching different oil inlets.

[0032] The above description of the embodiments is to facilitate those of ordinary skill in the art to understand and apply the present application. It is obvious that those familiar with the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without having to pay creative labor. Therefore, the present application is not limited to the embodiments herein, and improvements and modifications made by those skilled in the art based on the contents disclosed in the present application without departing from the scope and spirit of the present application are within the scope of the present application.

Claims

1. A self-circulating speed-changing three-cylinder structure, characterized in that: The three-cylinder structure includes a barrel, a cylinder body arranged inside the barrel and sealed, a large plunger arranged inside the cylinder body, and a small plunger arranged inside the large plunger, wherein the large plunger is T-shaped, and the large plunger includes a piston rod and a piston, the piston divides the cylinder body into an oil inlet area and an oil return area which are not connected to each other, the piston rod is located in the oil return area, and the front end of the piston rod penetrates the front end of the cylinder body and the barrel body and performs work externally; the interior of the large plunger is hollow, and the small plunger penetrates the rear ends of the barrel and the cylinder body and is fixed to the rear ends of the barrel and the cylinder body, the front end of the small plunger is inserted into the hollow area of ​​the large plunger, and the front end of the small plunger separates the hollow area of ​​the large plunger, the small plunger is provided with a second oil inlet and is connected to the hollow area of ​​the large plunger, and the oil inlet area is provided with a first oil inlet.

2. The self-circulating speed-changing three-cylinder structure according to claim 1, characterized in that: The space between the outer wall of the cylinder body and the inner wall of the barrel is filled with filling liquid, and the barrel is provided with a liquid replenishing port.

3. The self-circulating speed-changing three-cylinder structure according to claim 2, characterized in that: A first oil passage is provided between the cylinder and the oil inlet area, and a first check valve is provided on the first oil passage, and the first check valve allows the filling liquid to enter the oil inlet area.

4. The self-circulating speed-changing three-cylinder structure according to claim 2, characterized in that: A second oil passage is provided between the cylinder and the second oil inlet, and a second check valve is provided on the second oil passage, and the second check valve allows the filling liquid to enter the second oil inlet.

5. The self-circulating speed-changing three-cylinder structure according to claim 1, characterized in that: A sealing ring is provided at the front end of the small plunger, and the sealing ring matches the inner diameter of the large plunger.

6. The self-circulating speed-changing three-cylinder structure according to any one of claims 1 to 5, characterized in that: The oil return area is provided with an oil return port.

7. The self-circulating speed-changing three-cylinder structure according to claim 1, characterized in that: The first oil inlet and the second oil inlet are connected to the same hydraulic oil source.

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