Leakage-proof rotary joint for controlling temperature of long lead screw

Abstract

The invention relates to a leakage-proof rotary joint, in particular to a leakage-proof rotary joint for controlling the temperature of a long lead screw. The rotating head comprises a middle connecting pipe fixed to one end of a lead screw shaft through a bolt, a rotating head shell is arranged at the end, away from the lead screw shaft, of the middle connecting pipe, and a liquid passing cavity is formed in the rotating head shell. The exterior of the middle connecting pipe is protected through the arranged fixing sleeve, the limiting mechanism is used for limiting the middle connecting pipe, the stability of the middle connecting pipe in the rotating process is improved, the situation that cooling liquid leaks from the fixed side sealing ring and the rotating side sealing ring is reduced, and the service life of the cooling liquid is prolonged. And meanwhile, a liquid leakage cavity is formed in the fixed sleeve through the limiting mechanism and the rotating head shell, cooling liquid leaked from the fixed side sealing ring and the rotating side sealing ring can be collected in the liquid leakage cavity and is discharged through a leaked liquid discharging opening, and therefore the situation that the cooling liquid is directly discharged to pollute the rotating head shell and the middle connecting pipe is avoided.

Description

Technical Field

[0001] This invention relates to a leak-proof rotary joint, and more specifically, to a leak-proof rotary joint for temperature control of long lead screws. Background Technology

[0002] In mechanical equipment, there are rotating parts that must be maintained at appropriate temperatures to avoid variations in expansion coefficients, changes in machining accuracy, and abnormal wear caused by temperature changes. Examples include lead screws, heating rollers, and cooling rollers. In actual production, these screws or rollers are often designed as hollow structures, supplying a temperature-controlled fluid, such as coolant, to their interior. There are two installation methods for this temperature control. One method involves connecting rotary joints to both ends of the lead screw or roller, with external coolant supplied through one rotary joint to the lead screw or roller and then discharged through the other. The other method involves forming a dual flow path inside the shaft, where the fluid is redirected at the end of the flow path and discharged through the original rotary joint. When a drive unit is located on one end of a conveyor roller or lead screw, like in this case, maintaining the rotary joint on that side becomes cumbersome. Therefore, for short-length or low-speed applications, the second method, using a single rotary joint, is often employed.

[0003] In recent years, with the aim of improving productivity, conveyor rollers or lead screws have been trending towards longer dimensions and higher speeds, with rotational speeds reaching 1000-5000 revolutions per minute. When using a rotary joint for coolant input and output, the sealing effect of the connection between the lead screw and the rotary joint is crucial. Currently, the rotary joint and lead screw are installed separately, with the only connection being the end used for coolant delivery. However, this method is prone to rotational misalignment during lead screw operation, especially under load, easily leading to leakage at the connection point. The leaked oil flows directly from this connection, contaminating the surrounding working environment. Therefore, a rotary joint is needed that can improve the connection with the lead screw while preventing oil leakage and environmental pollution. Summary of the Invention

[0004] The purpose of this invention is to provide a leak-proof rotary joint for temperature control of long lead screws, so as to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides a leak-proof rotary joint for temperature control of long lead screws, comprising a central connecting pipe bolted to one end of the lead screw shaft, and a rotary head housing disposed at the end of the central connecting pipe away from the lead screw shaft. The rotary head housing is characterized by having a liquid-passing cavity inside, with an inlet and an outlet respectively connected to the liquid-passing cavity, the inlet and outlet penetrating the outer wall of the rotary head housing. A stator ring is fixedly connected inside the liquid-passing cavity. A connecting pipe head is fixedly attached to the end of the central connecting pipe away from the lead screw shaft, the connecting pipe head being rotatably inserted into the stator ring, and an insertion pipe is fixed inside the stator ring. The other end of the insertion pipe is inserted into the central connecting pipe and the lead screw shaft. The rotary head housing is located near... A floating seat is fixed to one end of the connecting pipe with screws. A fixed-side sealing ring is fixedly installed on the side of the floating seat away from the rotating head housing. A rotating-side sealing ring is fixed to the end of the connecting pipe near the connecting pipe head. The fixed-side sealing ring and the rotating-side sealing ring slide against each other. A fixed sleeve is fixed to the side of the rotating head housing near the connecting pipe with screws. The fixed sleeve encloses the connecting pipe and the floating seat. A limiting mechanism for restricting the connecting pipe is installed inside the fixed sleeve. A leakage cavity is formed between the limiting mechanism and the rotating head housing. A leakage outlet communicating with the leakage cavity is opened on the fixed sleeve. Coolant leaking from the fixed-side sealing ring and the rotating-side sealing ring enters the leakage cavity and is discharged through the leakage outlet.

[0006] As a further improvement to this technical solution, the floating seat is sleeved outside the central connecting pipe and sealed with the rotating head housing using a sealing ring. A cavity for coolant flow is left between the floating seat, the connecting pipe head, and the stator ring. At the same time, several drainage holes are arranged in a ring array at the connection position between the central connecting pipe and the connecting pipe head. The coolant inside the central connecting pipe communicates with the cavity through the drainage holes.

[0007] As a further improvement to this technical solution, the liquid inlet and liquid outlet are staggered, and the liquid outlet is located close to the central connecting pipe. The stator ring blocks the part where the liquid inlet and liquid outlet communicate in the liquid passage cavity, and the liquid outlet is connected to the cavity.

[0008] As a further improvement to this technical solution, the fixed-side sealing ring and the rotating-side sealing ring are located in the cavity near the leakage cavity, and the coolant in the cavity leaks into the leakage cavity through the gap between the fixed-side sealing ring and the rotating-side sealing ring.

[0009] As a further improvement to this technical solution, the limiting mechanism includes two sealed bearings fixedly sleeved on the connecting pipe. The outer ring of the sealed bearing is fixed inside the fixed sleeve and sealed with a sealing ring. A shaft inner retaining ring is provided between the two sealed bearings and on the side of the sealed bearing near the leakage cavity, which is snapped and fixed on the connecting pipe. The shaft inner retaining ring restricts the position of the sealed bearing in the connecting pipe.

[0010] As a further improvement to this technical solution, an outer retaining ring for the shaft is provided on the side of the sealed bearing away from the leakage cavity. The outer retaining ring for the shaft is snapped and fixed inside the fixed sleeve, and the outer retaining ring for the shaft prevents the sealed bearing and the connecting pipe from moving away from the rotating head housing.

[0011] Compared with the prior art, the beneficial effects of the present invention are as follows: In this leak-proof rotary joint for temperature control of long lead screws, a fixed sleeve protects the outside of the connecting pipe, and a limiting mechanism limits the connecting pipe, improving its stability during rotation and reducing coolant leakage from the fixed-side and rotating-side sealing rings. Simultaneously, a leakage cavity is formed inside the fixed sleeve by the limiting mechanism and the rotating head housing. Coolant leaking from the fixed-side and rotating-side sealing rings is collected in the leakage cavity and discharged through the leakage outlet, thus preventing direct discharge of coolant and contamination of the rotating head housing and connecting pipe. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is one of the schematic diagrams of the overall cross-sectional structure of the invention; Figure 3 The second schematic diagram of the overall cross-sectional structure of the invention; Figure 4 This is a cross-sectional structural diagram of the combination of the rotating head housing and the fixed sleeve of the invention. Figure 5 This is a schematic cross-sectional view of the connecting pipe of the present invention; Figure 6 One of the schematic diagrams showing the flow of coolant inside the overall device of the invention; Figure 7 This is the second schematic diagram of the internal coolant flow of the overall device of the invention.

[0013] The meanings of the labels in the diagram are as follows: 1. Rotating head housing; 11. Liquid passage chamber; 12. Liquid inlet; 13. Liquid outlet; 14. Stator ring; 15. Floating seat; 16. Fixed side sealing ring; 2. Fixed sleeve; 21. Shaft outer retaining ring; 22. Leakage outlet; 3. Connecting pipe; 31. Shaft inner retaining ring; 32. Sealed bearing; 33. Connecting pipe end; 34. Rotary side sealing ring; 35. Drain hole; 4. Lead screw shaft; 5. Insertion tube. Detailed Implementation

[0014] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0015] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0016] Example 1. Please refer to Example 1. Figures 1-5 As shown, this embodiment provides a leak-proof rotary joint for temperature control of long lead screws, including a central connecting pipe 3 bolted to one end of the lead screw shaft 4. The connection between the central connecting pipe 3 and the lead screw shaft 4 is sealed with a sealing ring. A rotary head housing 1 is provided at the end of the central connecting pipe 3 away from the lead screw shaft 4. A liquid-passing cavity 11 is formed inside the rotary head housing 1. The liquid-passing cavity 11 is connected to an inlet 12 and an outlet 13, which penetrate the outer wall of the rotary head housing 1. A stator ring 14 is fixedly connected inside the liquid-passing cavity 11, and a seal is used between the stator ring 14 and the rotary head housing 1. The ring is sealed and fixed. Both the inlet 12 and outlet 13 are connected to external pipes. The external pipes supply coolant to the inlet 12. The coolant enters the liquid passage chamber 11 through the inlet 12. A connecting pipe head 33 is fixed at the end of the connecting pipe 3 away from the lead screw shaft 4. The connecting pipe head 33 is rotatably inserted into the stator ring 14. There is sliding contact between the connecting pipe head 33 and the stator ring 14. An insertion pipe 5 is fixed inside the stator ring 14. A rubber ring is used to seal between the insertion pipe 5 and the stator ring 14. The other end of the insertion pipe 5 is inserted into the connecting pipe 3 and the lead screw shaft 4. (Reference) Figure 2Space is provided between the inner walls of the insertion tube 5, the connecting tube 3, and the lead screw shaft 4 for coolant to flow, and space is also provided between the end of the insertion tube 5 and the lead screw shaft 4, so as to ensure that coolant can flow from the insertion tube 5 to the space between the connecting tube 3 and the insertion tube 5.

[0017] A floating seat 15 is screwed to one end of the rotating head housing 1 near the connecting pipe 3. A sealing ring is used to seal between the floating seat 15 and the rotating head housing 1. A fixed-side sealing ring 16 is fixedly installed on the side of the floating seat 1 away from the rotating head housing 1. A rotating-side sealing ring 34 is fixed to one end of the connecting pipe 3 near the connecting pipe head 33. The fixed-side sealing ring 16 and the rotating-side sealing ring 34 slide against each other. When the connecting pipe 3 rotates smoothly, the fixed-side sealing ring 16 and the rotating-side sealing ring 34 can seal each other, preventing coolant from passing through the fixed-side sealing ring. The contact surface between 16 and the rotating side sealing ring 34 is fixed with a screw on the side of the rotating head housing 1 near the central connecting pipe 3. The fixed sleeve 2 wraps the central connecting pipe 3 and the floating seat 15 inside. The floating seat 15 is sleeved on the outside of the central connecting pipe 3. A cavity for coolant flow is left between the floating seat 15, the connecting pipe head 33 and the stator ring 14. At the same time, several drainage holes 35 are opened in a ring array at the position where the central connecting pipe 3 and the connecting pipe head 33 are connected. The coolant inside the central connecting pipe 3 communicates with the cavity through the drainage holes 35. The outlet 13 is connected to the cavity.

[0018] refer to Figures 6-7 Solid arrows indicate the normal flow trajectory of coolant, while hollow arrows indicate the trajectory of leaking oil. The inlet 12 and outlet 13 are staggered, with outlet 13 positioned closer to the central connecting pipe 3 and inlet 12 positioned further away from the central connecting pipe 3. The stator ring 14 blocks the connection between inlet 12 and outlet 13 in the liquid passage chamber 11. External pipes deliver coolant to the liquid passage chamber 11 through inlet 12, and then the coolant entering the liquid passage chamber 11 is delivered to the insertion pipe 5. The coolant that moves to the other end of the insertion pipe 5 flows into the interior of the lead screw shaft 4 and from the space between the lead screw shaft 4 and the insertion pipe 5 into the space between the central connecting pipe 3 and the insertion pipe 5. After the coolant flows into the space between the central connecting pipe 3 and the insertion pipe 5, the coolant flows through the drain hole 35 into the cavity between the float seat 15, the connecting pipe head 33, and the stator ring 14. The coolant entering the cavity enters the external pipe through outlet 13.

[0019] Coolant is supplied to the lead screw shaft 4 through the inlet 12 and discharged through the outlet 13. The flow of coolant helps to reduce the temperature of the lead screw shaft 4 and ensure its normal operation.

[0020] A limiting mechanism is installed inside the fixed sleeve 2 to restrict the rotation of the connecting pipe 3. The limiting mechanism stabilizes the rotation of the connecting pipe 3, reducing leakage between the fixed-side sealing ring 16 and the rotating-side sealing ring 34. At the same time, a leakage cavity is formed between the limiting mechanism and the rotating head housing 1. The fixed-side sealing ring 16 and the rotating-side sealing ring 34 are located in the cavity near the leakage cavity. The coolant in the cavity leaks into the leakage cavity through the gap between the fixed-side sealing ring 16 and the rotating-side sealing ring 34. The leakage cavity is used to receive the coolant leaking from between the fixed-side sealing ring 16 and the rotating-side sealing ring 34. A leakage outlet 22 connected to the leakage cavity is provided on the fixed sleeve 2. The coolant leaking from the fixed-side sealing ring 16 and the rotating-side sealing ring 34 enters the leakage cavity and is discharged through the leakage outlet 22, preventing the coolant from directly leaking to the outside of the lead screw shaft 4 and contaminating the surface of the lead screw shaft 4, thereby affecting the normal use of the lead screw shaft 4.

[0021] The limiting mechanism includes two sealed bearings 32 fixedly sleeved on the connecting pipe 3. The outer ring of the sealed bearing 32 is fixed inside the fixed sleeve 2, and a sealing ring is used to seal between the bearing and the fixed sleeve 2. (Refer to...) Figure 3 A baffle is formed at the end of the connecting pipe 3 near the lead screw shaft 4 where the sealing bearing 32 is installed. The side of the sealing bearing 32 near the lead screw shaft 4 contacts the side wall of the baffle. At the same time, an inner retaining ring 31 for shafts is provided between the two sealing bearings 32 and on the side of the sealing bearing 32 near the leakage chamber. The inner retaining ring 31 for shafts restricts the position of the sealing bearings 32 in the connecting pipe 3. The inner retaining ring 31 for shafts is fixed on the connecting pipe 3 and blocks the two sealing bearings 32, so that the two sealing bearings 32 can be stably fixed on the connecting pipe 3. The connecting pipe 3 is rotated and installed inside the fixed sleeve 2 through the sealing bearings 32, so that the connecting pipe 3 can be more stable when rotating. This avoids the situation where the gap between the fixed side sealing ring 16 and the rotating side sealing ring 34 expands due to the instability of the connecting pipe 3, thereby reducing the leakage between the fixed side sealing ring 16 and the rotating side sealing ring 34.

[0022] Meanwhile, a shaft outer retaining ring 21 is provided on the side away from the leaking chamber sealing bearing 32. The shaft outer retaining ring 21 is snapped and fixed inside the fixed sleeve 2. One side of the shaft outer retaining ring 21 contacts the side wall of the sealing bearing 32 near the lead screw shaft 4. The shaft outer retaining ring 21 prevents the sealing bearing 32 and the connecting pipe 3 from moving away from the rotating head housing 1, so that the connecting pipe head 33 and the stator ring 14 can be stably connected, avoiding the situation of loosening between the stator ring 14 and the connecting pipe head 33, and ensuring the stability of the connection between the connecting pipe head 33 and the stator ring 14.

[0023] The space formed by the sealed bearing 32, the rotating head housing 1, the fixed sleeve 2, the floating seat 15, and the connecting pipe 3 is the leakage chamber. When leakage occurs in the gap between the fixed side sealing ring 16 and the rotating side sealing ring 34, the leaked coolant enters the leakage chamber and is then discharged through the leakage outlet 22. This avoids the previous situation where the coolant leaking from between the fixed side sealing ring 16 and the rotating side sealing ring 34 dripped directly, and prevents the outside of the lead screw shaft 4 from being contaminated by coolant.

[0024] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A leak-proof rotary joint for temperature control of a long lead screw, comprising a central connecting pipe (3) bolted to one end of the lead screw shaft (4), wherein a rotary head housing (1) is provided at the end of the central connecting pipe (3) away from the lead screw shaft (4), characterized in that: The rotating head housing (1) has a liquid-filled cavity (11) inside, with an inlet (12) and an outlet (13) connected to it. The inlet (12) and outlet (13) penetrate the outer wall of the rotating head housing (1). A stator ring (14) is fixedly connected inside the liquid-filled cavity (11). A connecting pipe head (33) is fixed at one end of the connecting pipe (3) away from the lead screw shaft (4). The connecting pipe head (33) is rotatably inserted into the stator ring (14). An insertion pipe (5) is fixed inside the stator ring (14). The other end of the insertion pipe (5) is inserted into the connecting pipe (3) and the lead screw shaft (4). A floating seat (15) is screwed to one end of the rotating head housing (1) near the connecting pipe (3). The floating seat (15) is located on the side away from the rotating head housing (1). A fixed side sealing ring (16) is fixedly installed. A rotating side sealing ring (34) is fixed at one end of the central connecting pipe (3) near the connecting pipe head (33). The fixed side sealing ring (16) and the rotating side sealing ring (34) slide and rub against each other. A fixed sleeve (2) is fixed to one side of the rotating head housing (1) near the central connecting pipe (3) with screws. The fixed sleeve (2) wraps the central connecting pipe (3) and the floating seat (15) inside. A limiting mechanism for restricting the central connecting pipe (3) is installed inside the fixed sleeve (2). A leakage cavity is formed between the limiting mechanism and the rotating head housing (1). A leakage outlet (22) connected to the leakage cavity is opened on the fixed sleeve (2). Coolant leaking from the fixed side sealing ring (16) and the rotating side sealing ring (34) enters the leakage cavity and is discharged through the leakage outlet (22).

2. The leak-proof rotary joint for temperature control of long lead screws according to claim 1, characterized in that: The floating seat (15) is fitted outside the central connecting pipe (3) and sealed with a sealing ring between it and the rotating head housing (1). A cavity for coolant flow is left between the floating seat (15), the connecting pipe head (33), and the stator ring (14). At the same time, several drain holes (35) are arranged in a ring array at the connection position between the central connecting pipe (3) and the connecting pipe head (33). The coolant inside the central connecting pipe (3) communicates with the cavity through the drain holes (35).

3. The leak-proof rotary joint for temperature control of long lead screws according to claim 1, characterized in that: The inlet (12) and outlet (13) are staggered, and the outlet (13) is located close to the central connecting pipe (3). The stator ring (14) blocks the part where the inlet (12) and outlet (13) are connected in the liquid passage cavity (11). The outlet (13) is connected to the cavity.

4. The leak-proof rotary joint for temperature control of long lead screws according to claim 3, characterized in that: The fixed-side sealing ring (16) and the rotating-side sealing ring (34) are located in the cavity near the leakage cavity. The coolant in the cavity leaks into the leakage cavity through the gap between the fixed-side sealing ring (16) and the rotating-side sealing ring (34).

5. The leak-proof rotary joint for temperature control of long lead screws according to claim 1, characterized in that: The limiting mechanism includes two sealed bearings (32) fixedly sleeved on the central connecting pipe (3). The outer ring of the sealed bearing (32) is fixed inside the fixed sleeve (2) and sealed with a sealing ring. A shaft inner retaining ring (31) is provided between the two sealed bearings (32) and on the side of the sealed bearing (32) near the leakage cavity. The shaft inner retaining ring (31) restricts the position of the sealed bearing (32) in the central connecting pipe (3).

6. The leak-proof rotary joint for temperature control of long lead screws according to claim 5, characterized in that: A shaft outer retaining ring (21) is provided on the side away from the leakage cavity of the sealing bearing (32). The shaft outer retaining ring (21) is snapped and fixed inside the fixed sleeve (2). The shaft outer retaining ring (21) prevents the sealing bearing (32) and the connecting pipe (3) from moving away from the rotating head housing (1).

Images