Hydraulic cylinder

Abstract

The hydraulic cylinder comprises a cylinder body, a piston is arranged in the cylinder body and connected with a piston rod, the piston rod penetrates through the piston, and a third sealing ring and a fourth sealing ring are arranged between the piston rod and the inner wall of the piston. A detection blind hole extending into the piston from the outer end face of the piston rod is formed in the piston rod, and a first channel extending to the outer wall of the piston rod from the detection blind hole in the radial direction is formed in the side wall of the piston rod. A first annular sealing groove and a second annular sealing groove are formed in the circumferential face of the piston, a first sealing ring and a second sealing ring are arranged in the first sealing groove and the second sealing groove respectively, an annular oil collecting groove is formed between the first sealing groove and the second sealing groove, and the oil collecting groove is connected with a second channel extending to the inner wall of the piston from the oil collecting groove in the radial direction. The second channel is communicated with the first channel; and a detection mechanism is arranged in the detection blind hole. According to the utility model, the inner leakage phenomenon can be detected and treated in time, and the performance of the hydraulic cylinder is ensured.

Description

Technical Field

[0001] The utility model belongs to the field of hydraulic equipment, in particular to a hydraulic cylinder. Background Art

[0002] Hydraulic cylinder is a commonly used power equipment. A typical hydraulic cylinder includes a cylinder body, a piston is arranged in the cylinder body, the piston is fixedly connected to a piston rod, the end of the piston rod extends out of the cylinder body, and the two sides of the piston are respectively a rod cavity and a rodless cavity, and the side walls of the rod cavity and the rodless cavity are both provided with oil holes.

[0003] The movement of the piston is driven by hydraulic oil. The hydraulic oil has a high pressure under the action of the oil pump, and oil leakage often occurs. Oil leakage is divided into external leakage and internal leakage. External leakage refers to the oil in the oil pipe and cylinder leaking to the outside; internal leakage refers to the oil in the cylinder leaking from the high-pressure chamber into the low-pressure chamber. For example, when the piston rod extends outward, the oil pressure in the rodless chamber is greater than the oil pressure in the rod chamber. Under the action of the pressure difference, the hydraulic oil in the rodless chamber enters the rod chamber. External leakage is generally easy to find and can be easily observed by the naked eye, and can be repaired in time, but internal leakage is difficult to find in time and cannot be repaired in time. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a hydraulic cylinder which can detect internal leakage in a relatively timely manner so as to facilitate timely maintenance.

[0005] In order to solve the above problems, the technical solution adopted by the utility model is as follows: a hydraulic cylinder comprises a cylinder body, a piston is arranged inside the cylinder body, the piston is connected to a piston rod, a rodless cavity and a rod cavity are arranged on both sides of the piston, the rodless cavity and the rod cavity are connected to a first oil hole and a second oil hole respectively,

[0006] The piston rod passes through the piston, and a third sealing ring and a fourth sealing ring are arranged between the piston rod and the inner wall of the piston; a detection blind hole extending from the outer end surface of the piston rod to the inside of the piston is arranged in the piston rod, and a first channel radially extending from the detection blind hole to the outer wall of the piston rod is arranged on the side wall of the piston rod; an annular first sealing groove and a second sealing groove are arranged on the circumferential surface of the piston, and a first sealing ring and a second sealing ring are arranged in the first sealing groove and the second sealing groove respectively, an annular oil collecting groove is arranged between the first sealing groove and the second sealing groove, and the oil collecting groove is connected to a second channel radially extending from the oil collecting groove to the inner wall of the piston, and the second channel is connected to the first channel; a detection mechanism is arranged in the detection blind hole.

[0007] Furthermore, the piston rod is connected to the piston via a locking nut.

[0008] Furthermore, a detachable pressure head is provided at the end of the piston rod, and the detection mechanism is installed on the pressure head.

[0009] Furthermore, the detection mechanism includes an image acquisition mechanism.

[0010] Furthermore, a capillary adsorption core is arranged in the second channel and the first channel, one end of the capillary adsorption core extends into the oil collecting tank, and the other end extends into the detection blind hole.

[0011] Furthermore, the image acquisition mechanism is connected to a controller.

[0012] Furthermore, the number of the second channels and the number of the first channels are both three, and the three second channels and the three first channels are evenly distributed around the detection blind hole.

[0013] The beneficial effect of the utility model is that when the hydraulic cylinder is running, the first sealing ring and the second sealing ring slide relative to the inner wall of the cylinder body, and the risk of internal leakage is higher here. Therefore, an annular oil collecting groove is set between the first sealing groove and the second sealing groove. When internal leakage occurs, the hydraulic oil will reach the oil collecting groove regardless of whether it leaks from the rodless cavity into the rod cavity or from the rod cavity into the rodless cavity. When the hydraulic oil reaches the oil collecting groove, it will enter the oil collecting groove and flow into the detection blind hole through the second channel and the first channel. The detection mechanism can detect whether hydraulic oil appears in the blind hole. When hydraulic oil appears in the detection blind hole, it indicates that internal leakage has occurred and immediate maintenance is required.

[0014] It can be seen that the utility model can detect the internal leakage phenomenon relatively timely and deal with it in time, thereby ensuring the performance of the hydraulic cylinder. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the main cross-sectional view of the utility model;

[0016] Figure 2 yes Figure 1 A magnified schematic diagram of part A;

[0017] Figure numerals: 1—cylinder body; 2—piston; 3—piston rod; 4—rodless chamber; 5—rod chamber; 6—first oil hole; 7—second oil hole; 8—third sealing ring; 9—fourth sealing ring; 10—first channel; 11—first channel; 12—first sealing ring; 13—second sealing ring; 14—oil collecting tank; 15—second channel; 16—detection mechanism; 17—locking nut; 18—pressure head; 19—controller. DETAILED DESCRIPTION

[0018] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0019] The hydraulic cylinder of the utility model, such as Figure 1 and Figure 2As shown, it includes a cylinder body 1, a piston 2 is arranged inside the cylinder body 1, the piston 2 is connected to a piston rod 3, a rodless cavity 4 and a rod cavity 5 are arranged on both sides of the piston 2, and the rodless cavity 4 and the rod cavity 5 are respectively connected to a first oil hole 6 and a second oil hole 7. The piston 2 is slidably matched with the inner wall of the cylinder body 1, and the piston 2 can drive the piston rod 3 to move axially under the push of hydraulic oil. The first oil hole 6 and the second oil hole 7 are both connected to the external hydraulic system through oil pipes for the introduction and discharge of hydraulic oil.

[0020] The piston rod 3 passes through the piston 2, and a third sealing ring 8 and a fourth sealing ring 9 are arranged between the piston rod 3 and the inner wall of the piston 2; a detection blind hole 10 extending from its outer end surface to the inside of the piston 2 is arranged in the piston rod 3, and the detection blind hole 10 can be a circular hole or a square hole. The side wall of the piston rod 3 is provided with a first channel 11 extending radially from the detection blind hole 10 to the outer wall of the piston rod 3; an annular first sealing groove and a second sealing groove are arranged on the circumferential surface of the piston 2, and a first sealing ring 12 and a second sealing ring 13 are arranged in the first sealing groove and the second sealing groove, respectively, and an annular oil collecting groove 14 is arranged between the first sealing groove and the second sealing groove, and the cross section of the oil collecting groove 14 can be rectangular or semicircular. The oil collecting groove 14 is connected to a second channel 15 extending radially from the oil collecting groove 14 to the inner wall of the piston 2, and the second channel 15 is connected to the first channel 11. The first channel 11 and the second channel 15 are circular channels. The second channel 15 and the first channel 11 are both multiple, for example, three, and the three second channels 15 and the first channels 11 are evenly distributed around the detection blind hole 10. A detection mechanism 16 is provided in the detection blind hole 10, and the detection mechanism 16 can detect whether hydraulic oil appears at the bottom of the blind hole 10.

[0021] The first sealing ring 12, the second sealing ring 13, the third sealing ring 8 and the fourth sealing ring 9 are used to enhance the sealing effect and reduce the risk of internal leakage. The first sealing ring 12, the second sealing ring 13, the third sealing ring 8 and the fourth sealing ring 9 can be made of existing commonly used sealing materials. When the hydraulic cylinder is running, the first sealing ring 12 and the second sealing ring 13 will move with the piston 2 and slide with the inner wall of the cylinder body 1, and the sealing is more likely to fail. Therefore, an annular oil collecting groove 14 is set between the first sealing groove and the second sealing groove. The oil collecting groove 14 is located on the circumferential surface of the piston 2. When internal leakage occurs, whether it leaks from the rodless cavity 4 into the rod cavity 5, or from the rod cavity 5 into the rodless cavity 4, the hydraulic oil will reach the oil collecting groove 14. When the hydraulic oil reaches the oil collecting groove 14, it will enter the oil collecting groove 14 and flow into the detection blind hole 10 through the second channel 15 and the first channel 11. The detection mechanism 16 can detect whether hydraulic oil appears in the blind hole 10. When hydraulic oil appears in the detection blind hole 10, it indicates that internal leakage has occurred and immediate maintenance is required.

[0022] The piston rod 3 is connected to the piston 2 via a locking nut 17, which ensures a stable connection and facilitates installation and disassembly.

[0023] In order to facilitate the installation of the detection mechanism 16, a detachable pressure head 18 is provided at the end of the piston rod 13, and the detection mechanism 16 is installed on the pressure head 18. When the hydraulic cylinder is working, the pressure head is connected to the load component to provide thrust to the load component. The pressure head 18 can be specifically threadedly connected to the piston rod 13.

[0024] In the present invention, the detection mechanism 16 includes an image acquisition mechanism. The image acquisition mechanism may include an illuminating lamp bead and a micro camera. The illuminating lamp bead illuminates the detection blind hole 10, and the micro camera can take an image of the bottom of the detection blind hole 10. When hydraulic oil enters the detection blind hole 10, this phenomenon can be observed on the detection image, thereby judging that the hydraulic cylinder has internal leakage.

[0025] In addition, the detection mechanism 16 can also be a laser transceiver probe, which can emit and receive lasers. The piston rod 13 is usually made of metal. When the laser emitted by the laser transceiver probe reaches the bottom of the detection blind hole 10, it is reflected back and received by the laser transceiver probe. Since the optical properties of the hydraulic oil are different from the bottom of the detection blind hole 10 made of metal, when the hydraulic oil enters the detection blind hole 10, the laser emitted by the laser transceiver probe first reaches the hydraulic oil. At this time, the laser will be reflected, and at the same time, the laser penetrates the hydraulic oil and refracts. The intensity of the reflected laser received by the laser transceiver probe changes. Therefore, it is possible to judge whether internal leakage occurs based on the intensity of the reflected laser received by the laser transceiver probe.

[0026] When internal leakage occurs, in order to promote the hydraulic oil in the oil collecting tank 14 to flow quickly into the detection blind hole 10, so as to detect the internal leakage phenomenon more timely, the utility model is provided with a capillary adsorption core in the second channel 15 and the first channel 11, one end of the capillary adsorption core extends into the oil collecting tank 14, and the other end extends into the detection blind hole 10. The capillary adsorption core has a strong capillary adsorption effect, and can quickly absorb the hydraulic oil in the oil collecting tank 14 into the detection blind hole 10, and can be a material with a strong capillary force such as cotton thread.

[0027] In the present invention, the image acquisition mechanism is connected to a controller 19. The controller 19 can control the image acquisition mechanism to work automatically, for example, control the image acquisition mechanism to detect once every hour.

[0028] The above description is only the preferred embodiment of the utility model, and is not intended to limit the utility model. For those skilled in the art, the utility model can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A hydraulic cylinder, comprising a cylinder body (1), wherein a piston (2) is arranged inside the cylinder body (1), wherein the piston (2) is connected to a piston rod (3), wherein a rodless cavity (4) and a rod cavity (5) are respectively arranged on both sides of the piston (2), wherein the rodless cavity (4) and the rod cavity (5) are respectively connected to a first oil hole (6) and a second oil hole (7), wherein: The piston rod (3) passes through the piston (2), and a third sealing ring (8) and a fourth sealing ring (9) are arranged between the piston rod (3) and the inner wall of the piston (2); a detection blind hole (10) extending from the outer end surface of the piston rod (3) to the inside of the piston (2) is arranged in the piston rod (3), and a first channel (11) extending radially from the detection blind hole (10) to the outer wall of the piston rod (3) is arranged on the side wall of the piston rod (3); an annular first sealing groove and a second sealing groove are arranged on the circumferential surface of the piston (2), and a first sealing ring (12) and a second sealing ring (13) are arranged in the first sealing groove and the second sealing groove respectively; an annular oil collecting groove (14) is arranged between the first sealing groove and the second sealing groove, and the oil collecting groove (14) is connected to a second channel (15) extending radially from the oil collecting groove (14) to the inner wall of the piston (2), and the second channel (15) is communicated with the first channel (11); a detection mechanism (16) is arranged in the detection blind hole (10).

2. The hydraulic cylinder according to claim 1, characterized in that: The piston rod (3) is connected to the piston (2) via a locking nut (17).

3. The hydraulic cylinder according to claim 1, characterized in that: A detachable pressure head (18) is provided at the end of the piston rod (3), and the detection mechanism (16) is mounted on the pressure head (18).

4. The hydraulic cylinder according to claim 1, characterized in that: The detection mechanism (16) comprises an image acquisition mechanism.

5. The hydraulic cylinder according to claim 4, characterized in that: A capillary adsorption core is arranged in the second channel (15) and the first channel (11), one end of the capillary adsorption core extends into the oil collecting groove (14), and the other end extends into the detection blind hole (10).

6. The hydraulic cylinder according to claim 4, characterized in that: The image acquisition mechanism is connected to a controller (19).

7. The hydraulic cylinder according to claim 1, characterized in that: The number of the second channels (15) and the number of the first channels (11) are both three, and the three second channels (15) and the three first channels (11) are evenly distributed around the detection blind hole (10).

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