Automatic oil return structure

Abstract

The invention provides an automatic oil return structure. The automatic oil return structure comprises a piston assembly and a main body assembly, the piston assembly is provided with an inner sleeve, an outer sleeve and a displacement piece. The main body assembly is provided with a first main flow section communicated with the oil storage bag, a control blocking assembly, an operation plug body and a switching channel communicated with the first main flow section, the pressurization channel and the oil return channel. When the pressure of the first main flow section reaches the ultimate pressure, the pressure can push away the control blocking assembly and the operation assembly, so that the oil storage bag and the first main flow section are communicated, and the pressure of the first main flow section is reduced. Meanwhile, the switching blocking assembly moves to block the switching channel and the first main flow section channel and communicates the switching channel and the oil return channel, and therefore pressure relief and oil return can be continuously conducted.

Description

Technical Field

[0001] The invention relates to a piston pump, in particular to a piston pump used for hand tools such as clamping tools. Background Art

[0002] The prior art piston pump includes an oil storage bag, a drive assembly, and a piston. When the drive assembly is in operation, the oil in the oil storage bag is pumped out, and then the hydraulic oil is pressurized and pumped into the piston, thereby pushing the piston to move. In order to enable the piston to be quickly pushed to a fixed position and to be accurately controlled and fine-tuned when approaching the fixed position, the piston is pushed through the inner sleeve and the outer sleeve.

[0003] When the piston pump is just started, the drive assembly pumps hydraulic oil into the inner sleeve in order to quickly push the piston. Since the inner sleeve has a small diameter, a small amount of hydraulic oil can push the inner sleeve a long distance, so the piston can be pushed quickly. When the piston is close to the position, the drive assembly pumps hydraulic oil into the inner sleeve and the outer sleeve at the same time, so the movement speed of the piston changes, which can be accurately controlled and fine-tuned.

[0004] As the piston continues to move, when the piston hits the object to be squeezed, the oil pressure in the inner and outer sleeves will rise, and the pressure will gradually increase with the gradual squeezing. When the pressure reaches the set value, it means that the piston has been squeezed to the required degree. At this time, the safety valve will be pushed open by the pressure. At this time, the hydraulic oil in the inner and outer sleeves will return to the oil storage bag through the safety channel.

[0005] However, after the safety valve is opened, the pressure will return to zero instantly. Therefore, the safety valve is opened only for a moment and will soon be closed again because the pressure returns to zero. Therefore, in fact, only a very small amount of hydraulic oil will pass through the safety valve and return to the oil storage bag from the safety channel. At this time, the oil unloading rod must be further pressed to open the oil return channel. The user needs to continue pressing the oil unloading rod until all the hydraulic oil in the inner casing and the outer casing flows back from the oil return channel to the oil storage bag. Only in this way can the hydraulic oil flow from the piston back to the oil storage bag, but such operation is quite inconvenient.

[0006] In view of this, proposing a better improvement plan is an urgent problem to be solved in the industry. Summary of the invention

[0007] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present invention provides an automatic oil return structure, which is applied to a piston pump with inner and outer sleeves. When the oil pressure is greater than a set value, all the oil will automatically flow back to the oil storage bag.

[0008] In order to achieve the above-mentioned purpose of the invention, the technical means adopted by the present invention is to design an automatic oil return structure, which includes:

[0009] An oil storage bag containing hydraulic oil, wherein the hydraulic oil in the oil storage bag is maintained at a static pressure;

[0010] A piston assembly is spaced apart from the oil storage bag and comprises:

[0011] an inner sleeve having an inner passage;

[0012] A displacement member, which is sleeved on the inner sleeve and seals the outer wall surface of the inner sleeve;

[0013] a first oil storage chamber formed in the displacement member and connected to the inner passage;

[0014] an outer sleeve, which is sleeved on the displacement member; the displacement member seals the inner wall surface of the outer sleeve, and the displacement member can move relative to the inner sleeve and the outer sleeve; and

[0015] a second oil storage chamber formed between the outer sleeve, the inner sleeve, and the displacement member;

[0016] A main body assembly is disposed between the oil storage bag and the piston assembly and comprises:

[0017] a first main flow section connected to the oil storage bag;

[0018] a second main flow section, which is connected to the first oil storage chamber and the second oil storage chamber;

[0019] a first one-way blocking component, which can prevent the hydraulic oil from flowing to the oil storage bag through the first main flow section;

[0020] a second one-way blocking component, which can prevent the hydraulic oil from flowing to the second oil storage chamber through the second main flow section;

[0021] a switching channel connected to the first main flow section of the main flow channel;

[0022] a switching blocking component, which is disposed in the switching channel and selectively blocks the switching channel;

[0023] a pressurizing channel, one end of which is connected to the switching channel, and the other end of which is connected to the first oil storage chamber;

[0024] an oil return channel, one end of which is connected to the switching channel, and the other end of which is connected to the oil storage bag;

[0025] a control channel connected to the first main flow section;

[0026] a control blocking component, which is disposed in the control channel and selectively blocks the control channel;

[0027] an operating channel having a first operating section and a second operating section, wherein one end of the first operating section is connected to the control channel, and the other end is connected to the oil storage bag and the second operating section;

[0028] A first operating plug body, which is movably disposed in the first operating section of the operating channel, and the position where the control channel is connected to the first operating section and the position where the oil storage bag is connected to the first operating section are respectively located on both sides of the first operating plug body;

[0029] a second operating plug, which is disposed in the operating channel and selectively blocks the first operating section and the second operating section;

[0030] When the pressure of the first mainstream section is greater than a starting pressure, the pressure of the first mainstream section pushes the switching blocking component away, so that the switching blocking component moves and blocks the switching channel and the oil return channel, and the switching channel is kept in communication with the first mainstream section and the pressurizing channel, thereby the hydraulic oil flows into the first oil storage chamber through the inner channel; the starting pressure is greater than the static pressure;

[0031] When the pressure of the first mainstream section reaches a limit pressure, the pressure of the first mainstream section pushes open the control blocking component, so that the first mainstream section is connected to the first operating section, and the first operating plug moves to push open the second operating plug, whereby the second operating section is connected to the first operating section and the oil storage bag; when the second operating section is connected to the oil storage bag, the pressure of the first mainstream section drops to the static pressure; the limit pressure is greater than the starting pressure

[0032] When the pressure of the first mainstream section drops to the static pressure, the switching blocking component moves and blocks the switching channel and the first mainstream section, and the switching channel remains connected with the pressurizing channel and the oil return channel. Subsequently, the hydraulic oil flows from the first oil storage chamber through the inner channel, the pressurizing channel, and the oil return channel to the oil storage bag, and is pushed open by the second one-way blocking component by the second oil storage chamber to flow into the second mainstream section and flow through the pressurizing channel and the oil return channel to the oil storage bag.

[0033] Therefore, the advantage of the present invention is that when the pressure of the first mainstream section reaches the limit pressure, the pressure can push open the control blocking component and the operating plug, thereby connecting the oil storage bag, the first operating section, the second operating section, and the first mainstream section, so that the pressure of the first mainstream section decreases. At the same time, the switching blocking component moves to block the switching channel and the first mainstream section, and connects the switching channel and the oil return channel, so that the first oil storage chamber and the second oil storage chamber can remain connected to the oil storage bag and continue to release pressure and return oil.

[0034] In the automatic oil return structure as described above, the main body component has a first main flow channel and a main flow channel blocking member, and the main flow channel blocking member is arranged in the first main flow channel, whereby the first main flow channel forms the first main flow section and the second main flow section which are not connected.

[0035] In the automatic oil return structure as described above, the main body component has:

[0036] a main flow channel, one end of which is connected to the oil storage bag, and the other end of which is connected to the second oil storage chamber;

[0037] a third one-way blocking component, which can prevent the hydraulic oil from flowing to the oil storage bag through the main flow channel; and

[0038] A fourth one-way blocking component can prevent the hydraulic oil from flowing to the main flow channel through the second oil storage chamber.

[0039] In the automatic oil return structure as described above, the main body component has a communication channel, which is connected to the main flow channel and the first main flow section;

[0040] When the pressure of the first main flow section is greater than a pressurizing pressure, the hydraulic oil flows into the second oil storage chamber through the main flow channel; the limit pressure is greater than the pressurizing pressure, and the pressurizing pressure is greater than the starting pressure.

[0041] In the automatic oil return structure as described above, the main body component has:

[0042] a secondary flow channel, one end of which is connected to the oil storage bag, and the other end of which is connected to the second oil storage chamber; and

[0043] A secondary flow channel one-way blocking component can prevent the hydraulic oil from flowing to the secondary flow channel via the second oil storage chamber.

[0044] In the automatic oil return structure as described above, the first operating plug body has:

[0045] an inner flow channel formed in the first operating plug body;

[0046] a first opening formed on an end surface of the first operating plug body adjacent to the second operating plug body and connected to the inner flow channel and the oil storage bag;

[0047] a second opening connected to the inner flow channel and the control channel; and

[0048] An outer annular surface is sealed against the inner annular surface of the first operating section and is located between the first opening and the second opening.

[0049] In the automatic oil return structure as mentioned above:

[0050] The two ends of the switching channel are respectively a first switching port and a second switching port; the first switching port is connected to the first main flow section; the pressurizing channel is connected between the first switching port and the second switching port of the switching channel; the second switching port is connected to the oil return channel;

[0051] The switching blocking component comprises:

[0052] A switching plug body, which is movably disposed in the switching channel and selectively blocks the first switching port or the second switching port; the switching plug body has:

[0053] a switching plug ring convex portion, which is located in the switching channel, and a gap is formed between the outer annular surface of the switching plug ring convex portion and the inner annular surface of the switching channel;

[0054] a switching gasket, which is arranged in the switching channel and movably sleeved on the switching plug body, and the outer annular surface of the switching gasket is in contact with the inner annular surface of the switching channel, and a gap is formed between the inner annular surface of the switching gasket and the switching plug body; the inner diameter of the switching gasket is smaller than the outer diameter of the convex portion of the switching plug ring, whereby the switching gasket selectively abuts against the convex portion of the switching plug ring, and when the switching gasket abuts against the convex portion of the switching plug ring, the first section is blocked; and

[0055] A switching elastic member, which pushes against the switching gasket and causes the switching gasket to lean against the convex portion of the switching plug ring;

[0056] When the pressure of the first main flow section is less than the starting pressure, the switching plug body blocks the first switching port, and the switching gasket abuts against the convex portion of the switching plug ring;

[0057] When the pressure of the first mainstream section is greater than the starting pressure, the pressure of the first mainstream section causes the switching plug to move to open the first switching port and block the second switching port, thereby blocking the switching passage and the oil return passage; then the pressure of the first mainstream section causes the switching gasket to separate from the convex portion of the switching plug ring and open the first switching port, thereby connecting the first mainstream section with the pressurized passage;

[0058] When the pressure of the first main flow section drops to the static pressure, the switching plug moves to block the first switching port of the switching channel and opens the second switching port, thereby connecting the pressurizing channel and the oil return channel. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] The accompanying drawings described herein are only for explanation purposes and are not intended to limit the scope of the present invention in any way. In addition, the shapes and proportional dimensions of the various components in the figures are only schematic, used to help understand the present invention, and are not specifically limited to the shapes and proportional dimensions of the various components of the present invention. Those skilled in the art can select various possible shapes and proportional dimensions to implement the present invention according to the teachings of the present invention.

[0060] Figure 1 It is a schematic diagram of the present invention applied to a piston pump.

[0061] Figure 2 for Fig.15 A schematic cross-sectional view taken along the AA section line shows the cross section of the piston assembly.

[0062] Figure 3 for Fig.16 A schematic cross-sectional view of the BB cutting line, which shows the cross-section of the first main flow channel.

[0063] Figure 4 for Fig.16 A schematic cross-sectional view of the CC cutting line, showing the cross-section of the second main channel.

[0064] Figure 5 for Fig.16 A schematic cross-sectional view of the DD cutting line in the middle, which shows the cross-section of the connecting channel.

[0065] Figure 6 for Fig.18 A cross-sectional diagram of the EE cutting line in FIG. 5 , which shows the cross-section of the switching channel.

[0066] Fig. 6A It is a cross-sectional schematic diagram of the switch blocking component of the present invention blocking the first switch port.

[0067] Figure 6B It is a cross-sectional schematic diagram of the switch blocking component of the present invention blocking the second switch port.

[0068] Figure 7 for Fig.17 Schematic cross-sectional view of the FF cutting line, which shows the cross-section of the operating channel.

[0069] Fig. 7A It is a cross-sectional schematic diagram of the first operating plug body of the present invention.

[0070] Figure 8 for Fig.17 Schematic diagram of the cross section along the GG cutting line.

[0071] Fig. 9 for Fig.16A schematic cross-sectional view of the HH section line in the figure shows the cross-section of the control channel.

[0072] Fig.10 for Fig.15 Schematic diagram of the cross section along the II section line.

[0073] Fig.11 for Fig.16 Schematic diagram of the cross section along the JJ section line, which shows the cross section of the working channel.

[0074] Fig.12 for Fig.17 A schematic cross-sectional view of the KK cutting line in FIG. 1 , which shows the cross-section of the operating channel.

[0075] Fig.13 for Fig.18 A cross-sectional schematic diagram of the LL cutting line in the middle shows the cross-sections of the switching channel, the pressurizing channel, and the oil return channel.

[0076] Fig.14 for Fig.17 A cross-sectional schematic diagram along the MM cutting line shows that the pressurized channel is connected to the second main flow section.

[0077] Fig.15 It is a front view schematic diagram of the present invention.

[0078] Fig.16 It is a side view schematic diagram of the present invention.

[0079] Fig.17 It is a top view schematic diagram of the present invention.

[0080] Fig.18 It is an enlarged schematic diagram of the present invention. DETAILED DESCRIPTION

[0081] The details of the present invention can be more clearly understood with reference to the accompanying drawings and the description of the specific embodiments of the present invention. However, the specific embodiments of the present invention described herein are only used for the purpose of explaining the present invention and cannot be understood as limiting the present invention in any way. Under the guidance of the present invention, technicians can conceive of any possible variations based on the present invention, which should all be considered to belong to the scope of the present invention.

[0082] First, please refer to Figure 1 The present invention provides an automatic oil return structure, which includes an oil storage bag 10, a piston assembly 20, a main body assembly 30, and a driving assembly 40. The piston assembly 20 and the oil storage bag 10 are spaced apart, and the main body assembly 30 is located between the piston assembly 20 and the oil storage bag 10. The driving assembly 40 is connected to the main body assembly 30, and driven by the driving assembly 40, the hydraulic oil in the oil storage bag 10 flows through the main body assembly 30 and is pushed toward the piston assembly 20.

[0083] The oil storage bag 10 contains hydraulic oil, and the hydraulic oil in the oil storage bag 10 is kept at a static pressure. Since the capacity of the oil storage bag 10 is relatively large, when the pipeline of the automatic oil return structure of the present invention is connected to the oil storage bag 10, the hydraulic oil in the pipeline will also reach the static pressure.

[0084] Please refer to Figure 2 and Fig.15 The piston assembly 20 has an inner sleeve 21, a displacement member 22, and an outer sleeve 23, and can optionally have a reset elastic member 24, and is formed with a first oil storage chamber 201 and a second oil storage chamber 202. The inner sleeve 21 has an inner passage 210. The displacement member 22 is sleeved on the inner sleeve 21 and seals the outer wall surface of the inner sleeve 21. The outer sleeve 23 is sleeved on the displacement member 22, and the displacement member 22 seals the inner wall surface of the outer sleeve 23. The displacement member 22 can move relative to the inner sleeve 21 and the outer sleeve 23. The first oil storage chamber 201 is formed in the displacement member 22 and the first oil storage chamber 201 is connected to the inner passage 210, and the second oil storage chamber 202 is formed between the outer sleeve 23, the inner sleeve 21, and the displacement member 22. When the displacement member 22 moves, the volumes of the first oil storage chamber 201 and the second oil storage chamber 202 also change accordingly. The resetting elastic member 24 is used to reset the displacement member 22 to a position where the volumes of the first oil storage chamber 201 and the second oil storage chamber 202 are the smallest.

[0085] Please refer to Figures 3 to 18 The main body component 30 has two main channels (such as Figure 3 , Figure 4 ,and Fig.16 As shown), a connecting passage 32 (as Figure 5 and Fig.16 As shown), the second auxiliary flow channel 33 (as shown Figure 3 , Figure 4 ,and Fig.16 As shown), a switching channel 34 (as Fig.13 and Fig.18 As shown), a pressurized channel 35 (as Fig.13 and Fig.18 As shown), an oil return passage 36 (as shown Fig.13 and Fig.18 As shown), a control channel 37 (as Fig. 9 and Fig.16 As shown), and an operating channel 38 (as Fig.11 , Fig.12 , Fig.16 ,and Fig.17 shown).

[0086] like Figure 3 , Figure 4 ,and Fig.16As shown, one end of each main channel is connected to the oil storage bag 10 , and the other end is connected to the second oil storage chamber 202 , and a plurality of one-way blocking components are arranged at both ends of the main channel to limit the hydraulic oil from flowing into or out of the main channel 31 .

[0087] Specifically, the two main channels can be a first main channel 311 and a second main channel 312, respectively. In the present embodiment, a main channel blocking member 3111 is provided in the first main channel 311, whereby the first main channel 311 forms a first main section 3112 and a second main section 3113 which are not connected. However, in other embodiments, the first main section 3112 and the second main section 3113 can be two independent pipelines, rather than being formed in the same pipeline. The first main section 3112 is connected to the oil storage bag 10, and the second main section 3113 is connected to the inner channel 210 and the second oil storage chamber 202. The connecting channel 32 is connected to the second main channel 312 and the first main section 3112, whereby the pressure in the first main section 3112 is kept the same as the pressure in the second main channel 312.

[0088] The one-way blocking component may include a first one-way blocking component 3131, a second one-way blocking component 3132, a third one-way blocking component 3133, and a fourth one-way blocking component 3134. The first one-way blocking component 3131 is used to prevent the hydraulic oil from flowing to the oil storage bag 10 via the first main flow section 3112, and the second one-way blocking component 3132 is used to prevent the hydraulic oil from flowing to the second oil storage chamber 202 via the second main flow section 3113. The third one-way blocking component 3133 is used to prevent the hydraulic oil from flowing to the oil storage bag 10 via the second main flow channel 312, and the fourth one-way blocking component 3134 is used to prevent the hydraulic oil from flowing to the second main flow channel 312 via the second oil storage chamber 202.

[0089] One end of each secondary flow channel 33 is connected to the oil storage bag 10, and the other end is connected to the second oil storage chamber 202, so the pressure in the secondary flow channel 33 is the same as that in the oil storage bag 10, both of which are static pressure. A secondary flow channel one-way blocking component 330 is used to prevent the hydraulic oil from flowing to the secondary flow channel 33 through the second oil storage chamber 202. In other embodiments, there may be only one secondary flow channel 33.

[0090] like Figure 5 , Figure 6 ,and Fig.13As shown, the switching channel 34 is connected to the first mainstream section 3112, the pressurizing channel 35, and the oil return channel 36. In other words, the first mainstream section 3112, the pressurizing channel 35, and the oil return channel 36 are connected to each other through the switching channel 34. Specifically, one end of the pressurizing channel 35 is connected to the switching channel 34, and the other end is connected to the inner channel 210. One end of the oil return channel 36 is connected to the switching channel 34, and the other end is connected to the oil storage bag 10. In this embodiment, the switching channel 34 includes a first switching port 341 and a second switching port 342. The first switching port 341 is connected to the first mainstream section 3112. The pressurizing channel 35 is connected between the first switching port 341 and the second switching port 342 of the switching channel 34. The second switching port 342 is connected to the oil return channel 36.

[0091] Please refer to Fig. 6A and Figure 6B A switching blocking component 343 is disposed in the switching channel 34 and selectively blocks the switching channel 34 so that only two of the first main flow section 3112 , the pressurizing channel 35 , and the oil return channel 36 can communicate with each other at the same time.

[0092] The switching blocking assembly 343 has a switching plug body 3431, a switching gasket 3432, and a switching elastic member 3433. The switching plug body 3431 is movably disposed in the switching channel 34, and selectively moves to block the first switching port 341 or the second switching port 342. The switching plug body 3431 has a switching plug ring convex portion 3434, and a gap is formed between the outer annular surface of the switching plug ring convex portion 3434 and the inner annular surface of the switching channel 34.

[0093] The switching gasket 3432 is disposed in the switching channel 34 and is movably sleeved on the switching plug body 3431. The outer annular surface of the switching gasket 3432 is fitted to the inner annular surface of the switching channel 34, and a gap is formed between the inner annular surface of the switching gasket 3432 and the switching plug body 3431. The inner diameter of the switching gasket 3432 is smaller than the outer diameter of the switching plug ring convex portion 3434, whereby the switching gasket 3432 selectively abuts against one side of the switching plug ring convex portion 3434, and when the switching gasket 3432 abuts against the switching plug ring convex portion 3434, the switching channel 34 is blocked. The switching elastic member 3433 pushes against the switching gasket 3432, and causes the switching gasket 3432 to tend to abut against the switching plug ring convex portion 3434.

[0094] like Fig. 9 and Fig.16 As shown, the control channel 37 is connected to the first main flow section 3112 , and a control blocking component 370 is disposed in the control channel 37 to selectively block the control channel 37 .

[0095] like Figure 7 , Fig.11 , Fig.12 , Fig.16 ,and Fig.17 As shown, the operating channel 38 has a first operating section 381 and a second operating section 382. One end of the first operating section 381 is connected to the control channel 37, and the other end is connected to the oil storage bag 10 and the second operating section 382. A first operating plug 383 is movably disposed in the first operating section 381, and the position where the control channel 37 is connected to the first operating section 381 and the position where the first operating section 381 is connected to the oil storage bag 10 are respectively located on both sides of the first operating plug 383. A second operating plug 384 is disposed in the operating channel 38, and selectively blocks the first operating section 381 and the second operating section 382.

[0096] Please refer to Fig. 7A In this embodiment, the first operating plug body 383 has a first section 3831 and a second section 3832 connected to each other. The outer annular surface of the first section 3831 is sealed against the inner annular surface of the first operating section 381. The second section 3832 can pass through the connection between the first operating section 381 and the second operating section 382, ​​so it can move into the second operating section 382, ​​and a gap is formed between the outer annular surface of the second section 3832 and the inner wall surface of the connection between the first operating section 381 and the second operating section 382.

[0097] The first operating plug body 383 has an inner flow channel 3833, a first opening 3834, and a second opening 3835. The inner flow channel 3833 passes through the first section 3831 and the second section 3832 of the first operating plug body 383, and the first opening 3834 and the second opening 3835 are openings that connect the two ends of the inner flow channel 3833 to the outside, and the outer annular surface of the first section 3831 of the first operating plug body 383 is located between the first opening 3834 and the second opening 3835. Specifically, the first opening 3834 can be formed on the first section 3831 and connected to the inner flow channel 3833, the first operating section 381, and the control channel 37. The second opening 3835 can be formed on the first operating plug body 383 and connected to the inner flow channel 3833, the first operating section 381 or the second operating section 382, ​​and the oil storage bag 10. Specifically, the first opening 3834 can be formed on the first section 3831 adjacent to the end surface of the second operating plug body 384, and when the first section 3831 of the first operating plug body 383 enters the second operating section 382, ​​the first opening 3834 also enters the second operating section 382. In this embodiment, the cross-sectional area of ​​the first opening 3834 is much smaller than the cross-sectional area of ​​the inner flow channel 3833.

[0098] In addition, the first operating plug body 383 may also have a third opening 3836, which is formed in the second section 3832 of the first operating plug body 383 and is located in the first operating section 381, thereby connecting the inner flow channel 3833 and the first operating section 381. In this embodiment, the third opening 3836 is formed on the side of the first operating plug body 383. The cross-sectional area of ​​the third opening 3836 is much smaller than the cross-sectional area of ​​the inner flow channel 3833.

[0099] However, in other embodiments, the first operating plug body 383 may be solid without the inner flow channel 3833 , the first opening 3834 , the second opening 3835 , and the third opening 3836 .

[0100] Through the above structure, in the static state before starting, the pressure of the first main flow section 3112 is less than a starting pressure. Fig. 6A As shown, the switch plug 3431 blocks the first switch port 341 by the push of the switch elastic member 3433, and the switch gasket 3432 abuts against the switch plug ring convex portion 3434. In addition, the control blocking component 370 blocks the control channel 37, and the second operating plug 384 blocks the first operating section 381 and the second operating section 382.

[0101] When the piston pump is started, the driving component 40 allows the hydraulic oil to flow from the oil storage bag 10 into the first main flow section 3112 through the first one-way blocking component 3131, and into the second main flow channel 312 through the third one-way blocking component 3133. The first one-way blocking component 3131 and the third one-way blocking component 3133 can also prevent the hydraulic oil from flowing back. Therefore, the pressure in the first main flow section 3112 and the second main flow channel 312 is greater than the pressure in the oil storage bag 10.

[0102] When the pressure of the first mainstream section 3112 rises to a level greater than a preset starting pressure, the pressure of the first mainstream section 3112 pushes open the switching blocking component 343, causing the switching blocking component 343 to move and block the switching channel 34 and the return oil channel 36, and the switching channel 34 remains connected to the first mainstream section 3112 and the pressurized channel 35.

[0103] Specifically, when the pressure of the first main flow section 3112 is greater than the starting pressure, the pressure of the first main flow section 3112 causes the switching plug 3431 to move to open the first switching port 341, thereby maintaining communication between the first main flow section 3112 and the pressurizing channel 35. At the same time, the switching plug 3431 also blocks the second switching port 342, thereby blocking the switching channel 34 and the oil return channel 36. Figure 6BAs shown, the pressure of the first main flow section 3112 separates the switching gasket 3432 from the switching plug ring convex portion 3434 to open the switching channel 34, thereby connecting the first main flow section 3112 and the pressurizing channel 35, and allowing the hydraulic oil to flow from the first switching port 341 through the gap between the switching gasket 3432 and the switching plug ring convex portion 3434, and finally flow into the pressurizing channel 35. Therefore, the hydraulic oil flows into the inner channel 210 in sequence through the first main flow section 3112, the switching channel 34, the pressurizing channel 35, and then flows into the first oil storage chamber 201.

[0104] As the driving component 40 continues to pump the hydraulic oil into the first oil storage chamber 201, the first oil storage chamber 201 is expanded, causing the displacement member 22 to start moving. When the displacement member 22 moves, the volume of the second oil storage chamber 202 will also increase, so the second oil storage chamber 202 will be lower than the static pressure, so that the hydraulic oil can pass through the secondary flow channel one-way blocking component 330 from the oil storage bag 10 and be sucked into the second oil storage chamber 202 through the secondary flow channel 33. At this time, all the hydraulic oil pumped in through the driving component 40 enters the first oil storage chamber 201, so the displacement member 22 moves faster.

[0105] When the pressure of the first main flow section 3112 continues to increase to a value greater than a preset pressure, the hydraulic oil can push open the fourth one-way blocking component 3134 and flow into the second oil storage chamber 202 through the second main flow channel 312. At this time, the hydraulic oil pumped in by the driving component 40 enters the first oil storage chamber 201 and the second oil storage chamber 202 at the same time, so the moving speed of the displacement member 22 is slower, but the user can control the position of the displacement member 22 more accurately.

[0106] Since the driving component 40 does not continuously and stably push the hydraulic oil into the first mainstream section 3112 and the second mainstream channel 312, the pressure of the first mainstream section 3112 and the second mainstream channel 312 will fluctuate periodically. Under the periodic fluctuation of pressure, when the pressure of the first mainstream section 3112 continues to rise and is greater than a preset limit pressure at a certain moment, the pressure of the first mainstream section 3112 pushes the control blocking component 370 to connect the first mainstream section 3112 with the first operating section 381. Then the pressure of the first mainstream section 3112 will fluctuate slightly downward periodically. Since the first mainstream section 3112 and the second operating section 382 remain connected, the pressure of the two is the same. In other words, at the moment when the control blocking component 370 is pushed open, the pressure of the first operating section 381 is greater than the pressure of the second operating section 382 and the first mainstream section 3112, so that the first operating plug 383 can move to push the second operating plug 384, whereby the second operating section 382 is connected to the first operating section 381 and the oil storage bag 10. When the second operating section 382 is connected to the oil storage bag 10, the pressure of the first main flow section 3112 drops to the static pressure.

[0107] When the pressure of the first main flow section 3112 drops to the static pressure, the switching plug 3431 in the switching blocking component 343 is pushed back to the starting position by the switching elastic member 3433, that is, the first switching port 341 is blocked and the second switching port 342 is opened. Therefore, the switching blocking component 343 blocks the switching channel 34 from the first main flow section 3112, and the switching channel 34 is connected to the pressurizing channel 35 and the oil return channel 36. Subsequently, through the reset elastic member 24, the displacement member 22 moves to the starting position and compresses the first oil storage chamber 201 and the second oil storage chamber 202 to return the oil. At this time, the hydraulic oil flows from the first oil storage chamber 201 through the inner channel 210, the pressurizing channel 35, and the oil return channel 36 to the oil storage bag 10, and at the same time, the second one-way blocking component 3132 is pushed open by the second oil storage chamber 202 to flow into the second main flow section 3113, and then flows to the oil storage bag 10 through the pressurizing channel 35 and the oil return channel 36.

[0108] In addition, the user can also actively return the oil to release the pressure before reaching the limit pressure. Specifically, the user can press a pressure relief button, which is linked to the first operating plug 383, so that the first operating plug 383 can move to push the second operating plug 384, thereby connecting the second operating section 382 with the first operating section 381 and the oil storage bag 10, and reducing the pressure of the first main flow section 3112 to the static pressure.

[0109] The detailed explanation of the above-mentioned embodiments is only intended to explain the present invention so as to facilitate a better understanding of the present invention. However, these descriptions cannot be interpreted as limitations on the present invention for any reason. In particular, the various features described in different embodiments may also be arbitrarily combined with each other to form other embodiments. Unless there is a clear description to the contrary, these features should be understood to be applicable to any embodiment and are not limited to the described embodiments.

Claims

1. An automatic oil return structure, characterized in that: The automatic oil return structure comprises: An oil storage bag containing hydraulic oil, wherein the hydraulic oil in the oil storage bag is maintained at a static pressure; A piston assembly is spaced apart from the oil storage bag and comprises: an inner sleeve having an inner passage; A displacement member, which is sleeved on the inner sleeve and seals the outer wall surface of the inner sleeve; a first oil storage chamber formed in the displacement member and connected to the inner passage; an outer sleeve, which is sleeved on the displacement member; the displacement member seals the inner wall surface of the outer sleeve, and the displacement member can move relative to the inner sleeve and the outer sleeve; and a second oil storage chamber formed between the outer sleeve, the inner sleeve, and the displacement member; A main body assembly is disposed between the oil storage bag and the piston assembly and comprises: a first main flow section connected to the oil storage bag; a second main flow section, which is connected to the first oil storage chamber and the second oil storage chamber; a first one-way blocking component, which can prevent the hydraulic oil from flowing to the oil storage bag through the first main flow section; a second one-way blocking component, which can prevent the hydraulic oil from flowing to the second oil storage chamber through the second main flow section; a switching channel connected to the first main flow section; a switching blocking component, which is disposed in the switching channel and selectively blocks the switching channel; a pressurizing channel, one end of which is connected to the switching channel, and the other end of which is connected to the first oil storage chamber; an oil return channel, one end of which is connected to the switching channel, and the other end of which is connected to the oil storage bag; a control channel connected to the first main flow section; a control blocking component, which is disposed in the control channel and selectively blocks the control channel; an operating channel having a first operating section and a second operating section, wherein one end of the first operating section is connected to the control channel, and the other end is connected to the oil storage bag and the second operating section; a first operating plug body, which is movably disposed in the first operating section of the operating channel, and a position where the control channel is connected to the first operating section and a position where the oil storage bag is connected to the first operating section are respectively located on two sides of the first operating plug body; a second operating plug, which is disposed in the operating channel and selectively blocks the first operating section and the second operating section; When the pressure of the first mainstream section is greater than a starting pressure, the pressure of the first mainstream section pushes the switching blocking component away, so that the switching blocking component moves and blocks the switching channel and the oil return channel, and the switching channel is kept in communication with the first mainstream section and the pressurizing channel, thereby the hydraulic oil flows into the first oil storage chamber through the inner channel; the starting pressure is greater than the static pressure; When the pressure of the first mainstream section reaches a limit pressure, the pressure of the first mainstream section pushes open the control blocking component, so that the first mainstream section is connected to the first operating section, and the first operating plug moves to push open the second operating plug, whereby the second operating section is connected to the first operating section and the oil storage bag; when the second operating section is connected to the oil storage bag, the pressure of the first mainstream section drops to the static pressure; the limit pressure is greater than the starting pressure When the pressure of the first mainstream section drops to the static pressure, the switching blocking component moves and blocks the switching channel and the first mainstream section, and the switching channel remains connected to the pressurizing channel and the oil return channel. Subsequently, the hydraulic oil flows from the first oil storage chamber through the inner channel, the pressurizing channel, and the oil return channel to the oil storage bag, and the second one-way blocking component is pushed open by the second oil storage chamber to flow into the second mainstream section and flow to the oil storage bag through the pressurizing channel and the oil return channel.

2. The automatic oil return structure according to claim 1, characterized in that: The main body component has a first main flow channel and a main flow channel blocking member. The main flow channel blocking member is disposed on the first main flow channel, whereby the first main flow channel forms the first main flow section and the second main flow section which are not connected.

3. The automatic oil return structure according to claim 1, characterized in that: The main body component comprises: a main flow channel, one end of which is connected to the oil storage bag, and the other end of which is connected to the second oil storage chamber; a third one-way blocking component, which can prevent the hydraulic oil from flowing to the oil storage bag through the main flow channel; and A fourth one-way blocking component can prevent the hydraulic oil from flowing to the main flow channel through the second oil storage chamber.

4. The automatic oil return structure according to claim 3, characterized in that: The main body component has a communication channel, which is connected to the main flow channel and the first main flow section; When the pressure of the first main flow section is greater than a pressurizing pressure, the hydraulic oil flows into the second oil storage chamber through the main flow channel; the limit pressure is greater than the pressurizing pressure, and the pressurizing pressure is greater than the starting pressure.

5. The automatic oil return structure according to any one of claims 1 to 4, characterized in that: The main body component comprises: a secondary flow channel, one end of which is connected to the oil storage bag, and the other end of which is connected to the second oil storage chamber; and A secondary flow channel one-way blocking component can prevent the hydraulic oil from flowing to the secondary flow channel through the second oil storage chamber.

6. The automatic oil return structure according to any one of claims 1 to 4, characterized in that: The first operating plug body has: an inner flow channel formed in the first operating plug body; a first opening formed on an end surface of the first operating plug body adjacent to the second operating plug body and connected to the inner flow channel and the oil storage bag; a second opening connected to the inner flow channel and the control channel; as well as An outer annular surface is sealed against the inner annular surface of the first operating section and is located between the first opening and the second opening.

7. The automatic oil return structure according to any one of claims 1 to 4, characterized in that: The two ends of the switching channel are respectively a first switching port and a second switching port; the first switching port is connected to the first main flow section; the position where the pressurizing channel is connected to the switching channel is located between the first switching port and the second switching port; the second switching port is connected to the oil return channel; The switching blocking component comprises: A switching plug body, which is movably disposed in the switching channel and selectively blocks the first switching port or the second switching port; the switching plug body has: a switching plug ring convex portion, which is located in the switching channel, and a gap is formed between the outer annular surface of the switching plug ring convex portion and the inner annular surface of the switching channel; a switching gasket, which is arranged in the switching channel and can be movably sleeved on the switching plug body, and the outer annular surface of the switching gasket is in contact with the inner annular surface of the switching channel, and a gap is formed between the inner annular surface of the switching gasket and the switching plug body; the inner diameter of the switching gasket is smaller than the outer diameter of the convex portion of the switching plug ring, whereby the switching gasket selectively abuts against the convex portion of the switching plug ring, and when the switching gasket abuts against the convex portion of the switching plug ring, the first switching port is blocked; and A switching elastic member, which pushes against the switching gasket and causes the switching gasket to lean against the convex portion of the switching plug ring; When the pressure of the first main flow section is less than the starting pressure, the switching plug body blocks the first switching port, and the switching gasket abuts against the convex portion of the switching plug ring; When the pressure of the first mainstream section is greater than the starting pressure, the pressure of the first mainstream section causes the switching plug to move to open the first switching port and block the second switching port, thereby blocking the switching passage and the oil return passage; then the pressure of the first mainstream section causes the switching gasket to separate from the convex portion of the switching plug ring and open the first switching port, thereby connecting the first mainstream section with the pressurized passage; When the pressure of the first main flow section drops to the static pressure, the switching plug moves to block the first switching port of the switching channel and opens the second switching port, thereby connecting the pressurizing channel and the oil return channel.

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