Automatic rotating device for pipe expanding die and electric pipe expander

Abstract

The present application relates to the technical field of electric pipe expander, in particular to a kind of automatic rotating device of pipe expanding die and electric pipe expander thereof, including: limit seat, its inside is equipped with movable cavity;Push rod, its movable place is in movable cavity, and the front end of push rod is installed thimble;Rotary mechanism, it is sleeved on push rod, and place in movable cavity, and end movable clamping pipe expanding die;Wherein, the outer wall of push rod is axially symmetrical and is distributed with at least three raceways, and raceway has bending section;The inner wall of rotary mechanism is provided with the same number of ball as raceway, and the ball is placed in corresponding raceway;The reciprocating movement of push rod in limit seat makes ball roll along raceway, and ball passes through the bending section and drives rotary mechanism to reciprocate rotation in limit seat, to realize the rotation of pipe expanding die.The present application is axially symmetrical and is distributed with three raceways on the outer wall of push rod, and the cooperation between multiple raceways and ball is used to ensure the concentricity of push rod and one-way bearing, and it is more stable and long in service life to use.

Description

Technical Field

[0001] This invention relates to the field of electric pipe expander technology, and specifically to an automatic rotating device for pipe expander molds and its electric pipe expander. Background Technology

[0002] A pipe expander is a device that squeezes and enlarges one end of a pipe. The pipe can be a plastic pipe or a thin metal pipe.

[0003] Existing tube expander designs, such as Chinese Patent 2022205403704, describe a reset device and a novel tube expander, in which a cam groove is opened on the outer wall of the spindle, and the extension and retraction of the push rod is converted into the rotational force of the rotating seat by the cooperation of a one-way bearing and a ball, thereby driving the rotation of the support device.

[0004] Because it uses a single cam groove design, in actual use, it will give the spindle an external force that deviates from the axis. This will cause the spindle to press against the inner ring of the one-way bearing, generating additional friction, which will hinder the movement of the spindle and the rotation of the rotating seat. It will also affect the power transmission efficiency. After long-term use, it will also cause additional wear on the inner ring of the one-way bearing and the spindle, affecting the normal operation of the equipment. Summary of the Invention

[0005] The purpose of this invention is to provide an automatic rotating device for a tube expander and its electric expander. By symmetrically distributing three raceways on the outer wall of the push rod, and utilizing the cooperation between the multiple raceways and the balls, the concentricity of the push rod and the one-way bearing is ensured, thus solving the problems of easy wear, affecting rotation, and low transmission efficiency in the prior art.

[0006] The objective of this invention is achieved as follows:

[0007] An automatic rotating device for expanding pipe molds, comprising:

[0008] The limiting seat has a movable cavity inside;

[0009] The push rod is movable within the movable cavity, and a pin is installed at the front end of the push rod;

[0010] The rotating mechanism is sleeved on the push rod and placed in the movable cavity, with its end movably engaged with the expansion mold;

[0011] The push rod has at least three raceways symmetrically distributed on its outer wall, and each raceway has a bent section.

[0012] The inner wall of the rotating mechanism is provided with the same number of balls as the raceways, and the balls are placed in the corresponding raceways.

[0013] The reciprocating movement of the push rod within the limiting seat causes the ball to roll along the raceway. The ball passes through the bent section and drives the rotating mechanism to reciprocate within the limiting seat, thereby realizing the rotation of the expansion mold.

[0014] Preferably, the raceways are evenly distributed on the outer wall of the push rod.

[0015] Preferably, the inner wall of the raceway comprises:

[0016] The first arc-shaped section is located at the bottom of the raceway;

[0017] Two second arc-shaped portions are located on either side of the first arc-shaped portion;

[0018] When the ball is placed in the raceway, the outer wall of the ball moves against the second arc-shaped part, and there is a gap between the ball and the first arc-shaped part.

[0019] Preferably, the raceway has at least:

[0020] The first straight segment is distributed along the length of the push rod;

[0021] The second straight section is distributed along the length of the push rod and extends through the front end of the push rod.

[0022] The bend connects the first straight segment and the second straight segment, causing the first straight segment and the second straight segment to be misaligned.

[0023] Preferably, the rotating mechanism has at least the following features:

[0024] The rotating guide sleeve is rotatably set within the limiting seat, and the front end of the rotating guide sleeve is provided with a protruding tooth that cooperates with the tube expansion mold.

[0025] A one-way bearing is sleeved on the push rod, and the outer ring of the one-way bearing is connected to a rotating guide sleeve, while the inner ring is equipped with the aforementioned balls.

[0026] The rotation of the push rod, through the cooperation of the ball bearing and the guide bearing, causes the rotating guide sleeve to rotate unidirectionally within the limit seat.

[0027] Preferably, the outer wall of the front end of the rotating guide sleeve is provided with a damping groove, and a damping ring is installed in the damping groove. The outer wall of the damping ring slides against the inner wall of the limiting seat.

[0028] An electric pipe expander, comprising:

[0029] case;

[0030] The drive unit is installed inside the housing;

[0031] The aforementioned automatic rotating device for the expanding mold is connected to the driving device.

[0032] The outstanding and beneficial technical effects of this invention compared to the prior art are:

[0033] 1. The present invention is designed to ensure the concentricity of the push rod and the one-way bearing by symmetrically distributing three raceways on the outer wall of the push rod and utilizing the cooperation between the multiple raceways and the balls, thereby avoiding additional off-axis forces on the push rod, reducing wear between the push rod and the one-way bearing, and ensuring service life.

[0034] This also reduces friction and ensures stable motion.

[0035] 2. The design of the second arc-shaped part in this invention can support the ball, making the rolling of the ball more stable in the raceway, avoiding the ball from wobbling left and right in the raceway, further reducing wear, and making the operation more stable. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the overall structure of Embodiment 1 of the present invention.

[0037] Figure 2 This is an overall cross-sectional view of Embodiment 1 of the present invention.

[0038] Figure 3 This is a schematic diagram of the structure after concealing the housing and part of the driving device in Embodiment 1 of the present invention.

[0039] Figure 4 for Figure 3 A sectional view.

[0040] Figure 5 This is a partial structural diagram of the push rod and one-way bearing of Embodiment 1 of the present invention.

[0041] Figure 6 This is a schematic diagram of the push rod and steel ball in Embodiment 1 of the present invention.

[0042] Figure 7 for Figure 6 A cross-sectional view of BB.

[0043] Figure 8 for Figure 7 A magnified diagram of region A.

[0044] Figure 9 This is a partial structural diagram of the hidden limiting seat in Embodiment 1 of the present invention.

[0045] Figure label:

[0046] 1. Shell;

[0047] 2. Drive unit; 21. Motor; 22. Reducer; 23. Cam 1; 24. Battery;

[0048] 3. Automatic rotating device for expanding pipe mold; 31. Limiting seat; 311. Movable cavity; 32. Push rod; 321. Ejector pin; 322. Connecting column; 323. Connecting hole; 324. Elastic cylindrical pin; 33. Rotating mechanism; 331. Rotating guide sleeve; 332. One-way bearing; 333. Damping ring; 34. Raceway; 341. First arc-shaped part; 342. Second arc-shaped part; 343. First straight section; 344. Second straight section; 345. Bending section; 35. Ball bearing;

[0049] 4. Pipe expanding mold; 41. Locking cap; 42. Conical claw; 43. Tightening component;

[0050] 5. Elastic reset mechanism; 51. Spring 1; 52. Spring seat. Detailed Implementation

[0051] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0052] 【Example 1】

[0053] like Figure 1-2 As shown, an electric pipe expander includes a housing 1, a drive device 2, an automatic pipe expanding mold rotation device 3, and a pipe expanding mold 4. The drive device 2 and the automatic pipe expanding mold rotation device 3 are installed inside the housing 1, and the pipe expanding mold 4 is installed at the front end and is movably engaged with the front end of the automatic pipe expanding mold rotation device 3.

[0054] The drive device 2 is used to provide power. The output shaft of the drive device 2 is vertically arranged (the installation direction of the output shaft is not unique. In this embodiment, it is installed in a vertical direction). A cam 23 is installed on the output shaft, and the output shaft drives the cam 23 to rotate inside the housing 1.

[0055] like Figures 3-4 As shown, the automatic rotating device 3 for expanding pipe mold mainly includes a limit seat 31, a push rod 32 and a rotating mechanism 33, and multiple balls 35 are installed in the rotating mechanism 33.

[0056] Combination Figure 2 The limiting seat 31 is horizontally installed inside the housing 1. The limiting seat 31 has a movable cavity 311 that extends through the front and rear ends of the limiting seat 31. The rotating mechanism 33 is installed at the front end of the movable cavity 311. The push rod 32 is horizontally placed inside the movable cavity 311 and passes through the rotating mechanism 33. The front end of the push rod 32 is equipped with an ejector pin 321 that extends into the expansion mold 4. The rear end of the push rod 32 abuts against the outer wall of the cam 23. The rotation of the cam 23 will push the push rod 32 to move. In order to ensure telescopic movement, the push rod 32 is also provided with an elastic reset mechanism 5.

[0057] like Figures 5-7As shown, three raceways 34 are formed on the outer wall of the push rod 32. The raceways 34 are axially symmetrically distributed on the push rod 32 (i.e., the line C connecting the first raceway 34 and the axis of the push rod 32, and the line D connecting the third raceway 34 and the axis of the push rod 32, and the included angle α between C and D must be less than 180 degrees). The optimal solution is to distribute them evenly on the outer wall of the push rod 32.

[0058] The number of balls 35 is equal to the number of raceways 34, and the balls 35 are placed in the corresponding raceways 34. The movement of the push rod 32 causes the ejector pin 321 to open the expansion mold 4, and at the same time drives the expansion mold 4 to rotate through the rotating mechanism 33.

[0059] This type of pipe expander design ensures more uniform expansion of the pipe fittings, smooth inner walls, and reduces the risk of leakage after pipe installation.

[0060] The present invention, through the constraint of the ball bearing 35 and the raceway 34, ensures that the push rod 32 and the rotating mechanism 33 are always concentric. At the same time, the push rod and the one-way bearing only contact each other through the ball bearing. In this way, when the push rod 32 moves, it can avoid generating additional off-axis forces on the push rod 32, reduce the wear between the push rod 32 and the one-way bearing 332, and ensure service life.

[0061] like Figure 6 As shown, further configured, the raceway 34 has at least three sections, namely:

[0062] The first straight segment 343 is distributed along the length of push rod 32;

[0063] The second straight segment 344 is also distributed along the length of push rod 32 and passes through the front end of push rod 32.

[0064] The bending section 345 connects the first straight section 343 and the second straight section 344 at both ends, forming a complete and continuous raceway 34 while causing the first straight section 343 and the second straight section 344 to be staggered.

[0065] The design of the second straight section 344 passing through the front end of the push rod 32 is to facilitate the installation of the ball bearing 35 and the one-way bearing 332 on the push rod 32.

[0066] The straight section is used for the telescopic movement of push rod 32, so that ejector pin 321 can open the expansion mold 4.

[0067] With this design, under the extension and retraction of the push rod 32, when the ball bearing 35 passes through the bend section 345, it will drive the rotating mechanism 33 to rotate, thereby driving the tube expanding mold 4 to rotate and complete the rotating tube expanding action.

[0068] like Figure 8As shown, the inner wall of each segment of the raceway 34 includes: a first arcuate portion 341 and two second arcuate portions 342;

[0069] The first arc-shaped portion 341 is located at the bottom of the raceway 34;

[0070] The two second arc-shaped portions 342 are located on both sides of the first arc-shaped portion 341;

[0071] When the ball 35 is placed in the raceway 34, the outer wall of the ball 35 abuts against the second arc-shaped portion 342 and does not contact the first arc-shaped portion 341, and there will be a gap between the ball 35 and the first arc-shaped portion 341.

[0072] The design of the second arc-shaped portion 342 in this invention can support the ball 35, reduce contact and thus reduce wear. It also makes the rolling of the ball 35 in the raceway 34 more stable, avoiding the ball 35 from wobbling left and right in the raceway 34. The operation is more stable and smoother, reducing jamming.

[0073] like Figure 9 and Figure 4 As shown, the rotating mechanism 33 includes: a rotating guide sleeve 331 and a one-way bearing 332;

[0074] The rotating guide sleeve 331 is installed inside the limiting seat 31. Since there is a boss 1 inside the limiting seat 31 and a boss 2 outside the rotating guide sleeve 331, the boss 1 and the boss 2 will abut against each other, so the rotating guide sleeve 331 will not detach from the limiting seat 31 from the front end. The front end of the rotating guide sleeve 331 is circumferentially formed with several protruding teeth 1, and the rear end of the tube expansion mold 4 is circumferentially formed with protruding teeth 2. The protruding teeth 1 and the protruding teeth 2 can be engaged with each other under the action of the elastic reset mechanism 5.

[0075] The rotating guide sleeve 331 has a boss three inside. The one-way bearing 332 is installed inside the rotating guide sleeve 331 and its front end abuts against the boss three. Since the elastic reset mechanism 5 is always abutting against the rear end of the rotating guide sleeve 331, the one-way bearing 332 will not detach from the rotating guide sleeve 331.

[0076] The outer ring of the one-way bearing 332 is connected to the rotating guide sleeve 331. The connection and fixation with the rotating guide sleeve 331 can be achieved by interference fit. The inner ring of the one-way bearing 332 has several grooves for accommodating the balls 35. The number of grooves can be more than the number of balls 35. When in use, only the corresponding balls 35 need to be installed. The extra grooves can be used for subsequent replacement.

[0077] The rotation of the push rod 32, through the cooperation of the ball bearing 35 and the one-way bearing 332, causes the rotating guide sleeve 331 to rotate unidirectionally within the limiting seat 31.

[0078] like Figure 9As shown, a damping groove is further provided on the outer wall of the front end of the rotating guide sleeve 331, and a damping ring 333 is installed in the damping groove. The outer wall of the damping ring 333 slides against the inner wall of the limiting seat 31, and can also seal the gap.

[0079] The 333 damping ring can be an O-ring, which plays a damping role and ensures stability during use.

[0080] The front end of the ejector pin 321 is tapered, and the rear end protrudes with a connecting post 322. A connecting hole 323 is recessed in the front end face of the push rod 32. The connecting post 322 is inserted into the connecting hole 323, and then the connection between the ejector pin 321 and the push rod 32 is achieved by the elastic cylindrical pin 324.

[0081] This split design makes it easier to process and also allows for convenient replacement of ejector pin 321, avoiding waste.

[0082] like Figure 4 As shown, the structure of the expansion tube mold 4 is as follows:

[0083] The tube expanding mold 4 includes a locking cap 41, a cone claw 42, and a tightening member 43;

[0084] The lock cap 41 has a structure similar to a nut, with both ends through and internally threaded. Several tapered claws 42 are provided, which are circumferentially installed inside the lock cap 41 to form a cylinder. The outer wall of the tapered claws 42 has a stepped design, forming a tapered outer wall and a tapered space inside for the insertion of the ejector pin 321. A convex edge is formed on the outer wall of the rear end of the tapered claws 42, and a groove is formed at the end of the convex edge. The tightening member 43 is installed in the groove, thereby constraining and fixing several tapered claws 42, so that the tapered claws 42 have a tendency to shrink inward.

[0085] The tightening element 43 can tighten the spring at the end.

[0086] As the ejector pin 321 is inserted, it overcomes the elasticity of the tightening member 43, causing the cone claws 42 to separate from each other, thereby expanding the outer diameter surrounded by the cone claws 42 and achieving the purpose of expanding the tube.

[0087] like Figure 5 As shown, the structure of the elastic reset mechanism 5 is as follows:

[0088] The elastic reset mechanism 5 includes a spring seat 52 and a spring 51; the spring 51 is sleeved on the push rod 32 and its rear end abuts against the rear end of the push rod 32; the spring seat 52 is mounted on the push rod 32 and its end face abuts against the rear end of the rotating guide sleeve 331.

[0089] When the expansion mold 4 is not strong enough to expand thicker pipes, the push rod 32 always moves back and forth against the elastic force of the spring 51. At this time, the rotating guide sleeve 331 still rotates due to the action of the raceway and the ball. Under the influence of the first and second protrusions, the rotating guide sleeve 331 retracts as a whole, which plays a similar role to a clutch and avoids damage to the internal structure.

[0090] like Figure 2 As shown, the drive device 2 includes a motor 21, a reducer 22 and an output shaft. A battery 24 is installed at the lower end of the housing 1. The reducer 22 is installed at the output end of the motor 21 and the output shaft is connected to the reducer 22. For specific details, please refer to patent 2022205403704, which will not be elaborated here.

[0091] 【Example 2】

[0092] This embodiment is basically the same as the scheme of Embodiment 1, except that the number of raceways 34 can be four, five or more evenly arranged.

[0093] 【Example 3】

[0094] This embodiment is basically the same as the scheme of embodiment 1, except that the limiting seat 31 can be a part of the housing 1, and is not a separate part.

[0095] Working principle:

[0096] Initially, the rotating mechanism 33 is positioned at the second straight section 344 of the push rod 32. Then, the motor 21 is started, and under the action of the cam 23, the push rod 32 extends forward, opening the expanding mold 4. During this extension, the ball bearing 35 passes through the bending section 345. At this time, under the action of the one-way bearing 332, it will drive the rotating guide sleeve 331 to rotate at a certain angle. Because the first and second convex teeth are meshed, the expanding mold 4 is also driven to rotate at a certain angle until the ball bearing 35 moves onto the first straight section 343, ending the rotation of the guide sleeve 331. As cam 23 rotates, it does not provide forward thrust to push rod 32. Push rod 32 returns to the second straight section 344 under the action of spring 51. When it passes the bend, due to the one-way bearing 332, the rotating guide sleeve 331 is allowed not to rotate with the inner ring of the one-way bearing 332. At this time, one tube expansion operation is completed. The same action will be repeated to expand the tube multiple times. Each time the tube is expanded, the outer wall step of the tube expansion mold 4 can be inserted into the tube by one step until the desired tube expansion size is achieved.

[0097] The rotation of the tube expander 4 is completed before it comes into contact with the inner wall of the tube, and then it comes into contact with the inner wall of the tube to expand the tube.

[0098] 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 illustrative of the principles of 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 this invention is defined by the appended claims and their equivalents.

Claims

1. An automatic rotating device for a pipe expanding mold, characterized in that, include: The limiting seat (31) has a movable cavity (311) inside; A push rod (32) is movably placed in the movable cavity (311); a pin (321) is installed at the front end of the push rod (32); The rotating mechanism (33) is sleeved on the push rod (32) and placed in the movable cavity (311), with its end movably engaged with the expansion tube mold (4); Among them, at least three raceways (34) are symmetrically distributed on the outer wall of the push rod (32), and the raceways (34) have bent sections (345); The inner wall of the rotating mechanism (33) is provided with the same number of balls (35) as the raceways (34), and the balls (35) are placed in the corresponding raceways (34); The push rod (32) moves back and forth within the limiting seat (31), causing the ball (35) to roll along the raceway (34). The ball (35) passes through the bent section (345) and drives the rotating mechanism (33) to rotate back and forth within the limiting seat (31), thereby realizing the rotation of the expansion mold (4). The inner wall of the raceway (34) includes: The first arc-shaped portion (341) is located at the bottom of the raceway (34); Two second arc-shaped portions (342) are located on either side of the first arc-shaped portion (341); When the ball (35) is placed in the raceway (34), the outer wall of the ball (35) moves against the second arc-shaped part (342), and there is a gap between the ball (35) and the first arc-shaped part (341).

2. The automatic rotating device for expanding pipe mold according to claim 1, characterized in that: The raceways (34) are evenly distributed on the outer wall of the push rod (32).

3. The automatic rotating device for expanding pipe mold according to claim 1, characterized in that: The raceway (34) has at least the following features: The first straight segment (343) is distributed along the length of the push rod (32); The second straight section (344) is distributed along the length of the push rod (32) and passes through the front end of the push rod (32). The bend segment (345) connects the first straight segment (343) and the second straight segment (344), causing the first straight segment (343) and the second straight segment (344) to be misaligned.

4. The automatic rotating device for expanding pipe mold according to claim 1 or 2, characterized in that: The rotating mechanism (33) has at least the following features: The rotating guide sleeve (331) is rotatably set in the limiting seat (31), and the front end of the rotating guide sleeve (331) is provided with a protruding tooth that cooperates with the expansion mold (4); A one-way bearing (332) is sleeved on the push rod (32), and the outer ring of the one-way bearing (332) is connected to the rotating guide sleeve (331), and the inner ring is equipped with the ball (35); The rotation of the push rod (32) is achieved by the cooperation of the ball (35) and the one-way bearing (332), which causes the rotating guide sleeve (331) to rotate unidirectionally within the limiting seat (31).

5. The automatic rotating device for expanding pipe mold according to claim 4, characterized in that: The outer wall of the front end of the rotating guide sleeve (331) is provided with a damping groove, and a damping ring (333) is installed in the damping groove. The outer wall of the damping ring (333) slides against the inner wall of the limiting seat (31).

6. An electric pipe expander, characterized in that, include: Shell (1); The drive unit (2) is installed inside the housing (1); The automatic rotating device (3) for expanding tube mold as described in any one of claims 1-5, and connected to the driving device (2).

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