Double-spring reset hydraulic pipe expander

Abstract

The technical scheme belongs to the technical field of pipe expanders, and particularly relates to a double-spring reset hydraulic pipe expander which comprises an outer shell assembly, an inner shell assembly and an inner shell assembly. The pipe expanding assembly is movably arranged in the working cavity and used for expanding a pipe; the hydraulic assembly is arranged on the outer shell assembly and used for driving the pipe expanding assembly to work. Wherein the tube expanding assembly at least comprises a tube expanding unit, and the tube expanding unit is provided with a piston piece movably arranged in the working cavity and an expanding needle which is arranged on the piston piece and penetrates through the outer shell assembly; the reset disc spring set is provided with a force storage part and a deformation part, and a piston column of the piston piece movably abuts against the deformation part of the reset disc spring set; the front end of the reset spring abuts against the force storage part of the reset disc spring set, and the rear end of the reset spring abuts against the piston seat of the piston piece. Wherein the hydraulic assembly pushes the piston piece to compress the reset spring until the piston column compresses the reset disc spring set to complete pipe expansion, and at the moment, the reset disc spring set is matched with the reset spring to work together so that the piston piece can tend to retract towards the working cavity.

Description

Technical Field

[0001] The present technical solution relates to the technical field of tube expanders, and in particular to a double-spring reset hydraulic tube expander. Background Art

[0002] The hydraulic tube expander is a tool used to realize hydraulic expansion in the manufacture of heat exchangers in the fields of petrochemical, electric power, boiler, nuclear power, refrigeration, etc. It can expand the tube manually to enlarge the tube opening for easy docking.

[0003] Chinese patent CN220278085U discloses a manual hydraulic tube expander. When the tube expander is in use, the piston pushes forward to expand the tube, and the spring is compressed and shortened. Since the pipe clamps the cone head, when the spring's rebound force is insufficient, the cone head will get stuck and the piston cannot be reset. Summary of the invention

[0004] The purpose of this technical solution is to provide a double-spring reset hydraulic tube expander, which increases a reset disc spring group so that it cooperates with the reset spring to push and reset the piston, thereby solving the problem of the expansion needle getting stuck when the return force of the reset spring is insufficient.

[0005] The purpose of this technical solution is achieved in this way:

[0006] A double-spring return hydraulic tube expander comprises: an outer shell assembly having a working chamber therein; an expansion tube assembly movably arranged in the working chamber for expanding the tube; and a hydraulic assembly arranged on the outer shell assembly for driving the expansion tube assembly to work; wherein the expansion tube assembly comprises at least: an expansion tube unit having a piston member movably arranged in the working chamber and an expansion needle arranged on the piston member and passing through the outer shell assembly; a return disc spring group having a force storage part and a deformation part, the piston column of the piston member movably abutting the deformation part of the return disc spring group; and a return spring, the front end of which abuts the force storage part of the return disc spring group, and the rear end abuts the piston seat of the piston member; wherein the hydraulic assembly pushes the piston member to compress the return spring until the piston column compresses the return disc spring group to complete the tube expansion, at which time, the return disc spring group cooperates with the return spring to work together to make the piston member have a tendency to retract into the working chamber.

[0007] Preferably, the outer shell assembly comprises at least: an expander shell; and a connecting sleeve, which is threadedly connected to the expander shell and has an installation cavity therein, in which a gasket sleeve is fixedly arranged between the reset disc spring group and the reset spring; wherein the piston column passes through the gasket sleeve and movably abuts against the deformation portion of the reset disc spring group; and the front end of the reset spring abuts against the gasket sleeve.

[0008] Preferably, a step is formed in the connecting sleeve, the reset disc spring assembly is placed in the space surrounded by the step, and the front end of the cushion sleeve abuts against the step.

[0009] Preferably, the front end of the return spring is placed in the mounting groove of the cushion sleeve.

[0010] Preferably, the tube expansion unit further comprises: an expansion sleeve, which is threadedly connected to the front end of the connecting sleeve; and a plurality of expansion heads, which are arranged around the expansion needle and movably clamped in the expansion sleeve; wherein the expansion needle can push all the expansion heads to expand to achieve tube expansion.

[0011] Preferably, the front end of the expansion needle is tapered, and the expansion head is slidably connected to the expansion needle via an inclined surface adapted to the tapered surface.

[0012] Preferably, the hydraulic assembly at least comprises: an oil storage portion; an oil inlet pipeline, which is formed in the expander housing and connects the working chamber and the oil storage portion; and a hydraulic unit, which has a plunger movably arranged in the oil inlet pipeline; wherein, pressing the handle of the hydraulic unit can press the oil in the oil inlet pipeline into the working chamber through the plunger, so that the oil pushes the expansion needle through the piston to perform the tube expansion work.

[0013] Compared with the prior art, the technical solution has the following outstanding and beneficial technical effects:

[0014] 1. The reset disc spring group designed in the present technical solution can cooperate with the reset spring to push and reset the tube expansion unit. When the tube expansion unit begins to be pushed by the hydraulic assembly, the reset spring is compressed alone. During the tube expansion process, as the piston member gradually moves until the piston column abuts the reset disc spring group, this corresponds to the stage where the tube expansion is about to be completed. Therefore, when the piston member needs to be reset after the tube expansion is completed, the reset disc spring group can push the piston column, and at the same time the reset spring pushes the piston seat, and they work together to achieve the reset of the piston member.

[0015] 2. The reset spring designed in the technical solution can be arranged on the cushion sleeve, and the reset disc spring group is arranged between the cushion sleeve and the connecting sleeve. The piston member will abut against the reset disc spring group only when it moves gradually. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic diagram of the structure of Example 1.

[0017] Figure 2 This is an exploded view of the expansion tube assembly in Example 1.

[0018] Figure 3 This is a cross-sectional view of Example 1.

[0019] Figure 4 It is a cross-sectional view of the expansion tube assembly in Example 2.

[0020] Figure numerals: 1. outer shell assembly; 2. working chamber; 3. expansion assembly; 4. hydraulic assembly; 5. expansion unit; 6. piston member; 7. expansion needle; 8. return disc spring assembly; 9. force storage part; 10. deformation part; 11. piston column; 12. return spring; 13. piston seat; 14. expander housing; 15. connecting sleeve; 16. gasket; 17. step; 18. expansion sleeve; 19. expansion head; 20. oil storage part; 21. oil inlet pipeline; 22. hydraulic unit; 23. plunger; 24. handle. DETAILED DESCRIPTION

[0021] The specific implementation of the technical solution is further described in detail below with reference to the accompanying drawings.

[0022] [Example 1]

[0023] like Figure 1-3 As shown, a double spring return hydraulic tube expander comprises: an outer shell assembly 1, in which a plurality of chambers are formed, specifically a working chamber 2 for tube expansion, an oil inlet pipe 21 for oil flow, an oil storage portion 20 for storing oil, and a hydraulic chamber for hydraulic work, wherein the oil storage portion 20 can be externally connected to the outer shell assembly 1; a tube expansion assembly 3, which is movably arranged in the working chamber 2 for tube expansion; and a hydraulic assembly 4, which is arranged on the outer shell assembly 1 and is used to drive the tube expansion assembly 3 to work.

[0024] Specifically, the expansion tube assembly 3 at least comprises: an expansion tube unit 5, which has a piston member 6 movably arranged in the working chamber 2 and an expansion needle 7 arranged on the piston member 6 and passing through the outer shell assembly 1, the piston member 6 can drive the expansion needle 7 to move in the working chamber 2, the piston member 6 has a piston column 11 located at the front end and a piston seat 13 located at the rear end, the rear end of the piston seat 13 blocks the oil and moves under its thrust; a reset disc spring group 8, which has a force storage part 9 and a deformation part 10. Due to its structural characteristics, the outer edge of the disc spring is the force storage part 9. When it is compressed, the force storage part 9 is less deformed, and the inner edge is the deformation part 10. When it is compressed, the deformation part 10 is more deformed. The piston column 11 of the piston member 6 movably abuts the deformation part 10 of the reset disc spring group 8; and a reset spring 12, the front end of which abuts the force storage part 9 of the reset disc spring group 8, and the rear end abuts the piston seat 13 of the piston member 6.

[0025] like Figure 1-3As shown, the outer shell assembly 1 comprises at least: a tube expander shell 14; and a connecting sleeve 15, which is threadedly connected to the tube expander shell 14 and has an installation cavity therein, in which a cushion sleeve 16 located between the reset disc spring group 8 and the reset spring 12 is fixedly arranged; wherein, the piston column 11 passes through the cushion sleeve 16 and movably abuts against the deformation portion 10 of the reset disc spring group 8; the front end of the reset spring 12 abuts against the cushion sleeve 16, and the middle part of the cushion sleeve 16 has a through hole for the expansion needle 7 and the piston column 11 to pass through, and the inner diameter of the through hole is larger than the inner diameter of the reset disc spring group 8 and smaller than the outer diameter of the reset disc spring group 8.

[0026] Specifically, the gasket 16 is used to limit the reset disc spring group 8. Its front end abuts the reset disc spring group 8, and its rear end abuts the reset spring 12. Since it is fixedly arranged in the working chamber 2, it can apply the elastic force of the reset spring 12 to the piston member 6 to make it return to its original position.

[0027] Furthermore, when the piston member 6 begins to move under pressure, the return spring 12 is first compressed, and the return spring 12 accumulates elastic potential energy. At this time, the expansion needle 7 performs preliminary expansion on the tube; when the piston member 6 continues to move, the piston column 11 at the front end abuts against the return disc spring group 8 and compresses it. At this time, the expansion needle 7 performs deep expansion on the tube. Because the pressure of the tube on the expansion needle 7 is relatively large at this time, a larger elastic force is required to make the piston member 6 return to its original position. Therefore, the return disc spring group 8 and the return spring 12 cooperate to push the piston member 6 to return. When the expansion is completed, the return disc spring group 8 pushes the piston column 11 back, and the return spring 12 pushes the piston seat 13 back, so that the piston member 6 can be returned to its original position.

[0028] like Figure 2 and Figure 3 As shown, a step 17 is formed at the front end of the connecting sleeve 15, the reset disc spring group 8 is placed in the space surrounded by the step 17, the front end of the gasket sleeve 16 abuts against the step 17, the front end of the reset spring 12 is placed in the mounting groove of the gasket sleeve 16, and the front end of the gasket sleeve 16 abuts against the step 17, which can increase the stability of the reset disc spring group 8 in the working chamber 2, and an installation groove is recessed inwardly on the gasket sleeve 16, which is used to limit the front end of the reset spring 12, so that the transmission efficiency of the reset spring 12 is higher.

[0029] like Figure 2 and Figure 3As shown, the tube expansion unit 5 also includes: an expansion sleeve 18, which is threadedly connected to the front end of the connecting sleeve 15; and a plurality of expansion heads 19, which are arranged on the peripheral side of the expansion needle 7 and are movably clamped in the expansion sleeve 18; wherein, the expansion needle 7 can push all the expansion heads 19 to expand to achieve tube expansion, the front end of the expansion needle 7 is conical, and the expansion head 19 is slidably connected to the expansion needle 7 through an inclined surface adapted to the conical surface, and the end side of the expansion head 19 is movably placed in the clamping groove of the expansion sleeve 18, and a spring coil is arranged in the clamping groove for realizing the synchronous retraction of all the expansion heads 19. When the expansion needle 7 is retracted, the spring coil can make all the expansion heads 19 move toward each other and reset.

[0030] like Figure 3 As shown, the hydraulic assembly 4 at least comprises: an oil storage portion 20; an oil inlet pipeline 21, which is formed in the expander housing 14 and connects the working chamber 2 and the oil storage portion 20; and a hydraulic unit 22, which has a plunger 23 movably arranged in the oil inlet pipeline 21; wherein, by pressing the handle 24 of the hydraulic unit 22, the oil in the oil inlet pipeline 21 can be pressed into the working chamber 2 through the plunger 23, so that the oil pushes the expansion needle 7 through the piston member 6 to perform the expansion work.

[0031] [Example 2]

[0032] The configuration of this embodiment is substantially the same as that of embodiment 1, with the only difference being that the setting of the gasket sleeve 16 is cancelled, and the reset spring 12 directly abuts against the force storage portion 9 of the reset disc spring group 8. Since the degree of deformation of the force storage portion 9 of the reset disc spring group 8 under compression is less than that of the deformation portion 10, the piston column 11 can abut against the reset disc spring group 8, so that the reset disc spring group 8 can help the piston member 6 to return to its original position.

[0033] The above shows and describes the basic principle and main features of the technical solution and the advantages of the technical solution. The technicians in this industry should understand that the technical solution is not limited by the above embodiments. The above embodiments and the description are only to illustrate the principle of the technical solution. Without departing from the spirit and scope of the technical solution, the technical solution will have various changes and improvements, which fall within the scope of the technical solution to be protected. The scope of protection claimed by the technical solution is defined by the attached claims and their equivalents.

Claims

1. A double spring return hydraulic tube expander, characterized in that: include: An outer shell component (1) having a working chamber (2) therein; A tube expansion assembly (3), which is movably arranged in the working chamber (2) and is used for tube expansion; as well as A hydraulic assembly (4), which is arranged on the outer shell assembly (1) and is used to drive the tube expansion assembly (3) to work; Wherein, the expansion tube assembly (3) at least comprises: An expansion tube unit (5) comprising a piston member (6) movably arranged in the working chamber (2) and an expansion needle (7) arranged on the piston member (6) and passing through the outer shell component (1); A return disc spring assembly (8) having a force storage portion (9) and a deformation portion (10), wherein the piston column (11) of the piston member (6) movably abuts against the deformation portion (10) of the return disc spring assembly (8); and A return spring (12), the front end of which abuts against the force storage portion (9) of the return disc spring assembly (8), and the rear end of which abuts against the piston seat (13) of the piston member (6); The hydraulic assembly (4) pushes the piston member (6) to compress the return spring (12) until the piston column (11) compresses the return disc spring group (8) to complete the tube expansion. At this time, the return disc spring group (8) cooperates with the return spring (12) to work together to make the piston member (6) have a tendency to retract into the working chamber (2).

2. A double spring return hydraulic tube expander according to claim 1, characterized in that: The outer shell component (1) at least comprises: a tube expander housing (14); and A connecting sleeve (15) is threadedly connected to the tube expander housing (14) and has a mounting cavity therein, wherein a cushion sleeve (16) is fixedly disposed in the mounting cavity and is located between the return disc spring assembly (8) and the return spring (12); Wherein, the piston column (11) passes through the cushion sleeve (16) and movably abuts against the deformation portion (10) of the return disc spring assembly (8); The front end of the return spring (12) abuts against the cushion sleeve (16).

3. A double spring return hydraulic tube expander according to claim 2, characterized in that: A step (17) is formed inside the connecting sleeve (15), the return disc spring assembly (8) is placed in a space surrounded by the step (17), and the front end of the cushion sleeve (16) abuts against the step (17).

4. A double spring return hydraulic tube expander according to claim 3, characterized in that: The front end of the return spring (12) is placed in the installation groove of the cushion sleeve (16).

5. A double spring return hydraulic tube expander according to claim 4, characterized in that: The tube expansion unit (5) further comprises: An expansion sleeve (18) threadedly connected to the front end of the connecting sleeve (15); and A plurality of expansion heads (19), which are arranged on the peripheral side of the expansion needle (7) and are movably engaged in the expansion sleeve (18); The expansion needle (7) can push all the expansion heads (19) to expand so as to achieve tube expansion.

6. A double spring return hydraulic tube expander according to claim 5, characterized in that: The front end of the expansion needle (7) is tapered, and the expansion head (19) is slidably connected to the expansion needle (7) via an inclined surface adapted to the tapered surface.

7. A double spring return hydraulic tube expander according to claim 6, characterized in that: The hydraulic assembly (4) at least comprises: Oil storage department (20); an oil inlet pipe (21) formed in the tube expander housing (14) and communicating with the working chamber (2) and the oil storage portion (20); and A hydraulic unit (22) having a plunger (23) movably arranged in the oil inlet pipeline (21); By pressing the handle (24) of the hydraulic unit (22), the oil in the oil inlet pipe (21) can be pressed into the working chamber (2) via the plunger (23), so that the oil pushes the expansion needle (7) through the piston (6) to perform the tube expansion operation.

Images