Pipe expander

Abstract

The utility model discloses a pipe expanding machine, which belongs to the technical field of electric tools, and comprises a pipe expanding die, an ejector pin driven by a driving device and an intermittent turning assembly, the intermittent turning assembly comprises a push rod driven by the driving device, a rotating piece arranged in a rotatable manner and a turning piece arranged between the rotating piece and the pipe expanding die, and the push rod is in linkage fit with the rotating piece. A transmission structure capable of being separated and combined is arranged between the rear end of the shifting and rotating part and the rotating part, a meshing structure is arranged between the front end of the shifting and rotating part and the clamping jaws, the push rod can intermittently move front and back under driving of the driving device, the push rod moving forwards drives the rotating part to rotate around the central axis of the rotating part, and the rotating part drives the clamping jaws to rotate through the shifting and rotating part. The structure of the ejector pin is reasonably simplified, the situation that the ejector pin needs to drive the shifting piece to rotate and rotation blocking is prone to occurring is avoided, and meanwhile the forward-backward moving smoothness of the ejector pin and the smoothness that the intermittent shifting assembly drives the clamping jaw to rotate are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of electric tools, in particular to a pipe expanding machine. Background Art

[0002] The pipe expander is mainly used for connecting pipes. When in use, the pipe expander is first used to expand one end of the pipe, and then the other pipe is inserted into the expanded end of the pipe, and then the two pipes are compressed by a crimping tool to complete the connection. In actual operation, in order to improve the expansion effect of the pipe, it is generally necessary to expand the end of the pipe multiple times. Usually, after each expansion action, the clamping claw is retracted and rotated to a certain angle, and then expanded again until the clamping claw rotates roughly one circle. In order to improve work efficiency, some existing pipe expanders are designed with a dial structure that can intermittently drive the clamping claw to rotate a certain angle after the expansion action is completed. However, the existing dial structure is generally driven directly by the ejector pin that moves back and forth to drive the clamping claw to retract and expand. The structure of the ejector pin is relatively complex and easily causes the ejector pin to stall, which is not conducive to improving the user experience. Utility Model Content

[0003] In order to address the shortcomings and deficiencies in the above-mentioned prior art, the utility model provides a pipe expanding machine, which reasonably simplifies the structure of the ejector pin, avoids the situation where the ejector pin is easily blocked due to the need to drive the rotating member to rotate, and improves the smoothness of the forward and backward movement of the ejector pin and the smoothness of the intermittent rotating assembly driving the clamping claw to rotate.

[0004] In order to achieve the above technical objectives, the pipe expanding machine provided by the present invention includes:

[0005] The tube expansion die comprises a plurality of claws distributed along the circumference and capable of being retracted or expanded;

[0006] The ejector is driven by a driving device. The forward movement of the ejector forces the jaws to open, while the backward movement of the ejector releases the jaws so that they can be retracted.

[0007] An intermittent rotating assembly is used to drive the clamping jaws that have finished opening to rotate around the central axis of the tube expansion die;

[0008] The intermittent dial assembly includes a push rod driven by a driving device, a rotatable rotating part, and a dial part provided between the rotating part and the pipe expansion mold. The push rod and the rotating part cooperate with each other, and a clutch transmission structure is provided between the rear end of the dial part and the rotating part. An engaging structure is provided between the front end of the dial part and the claw. The push rod can move back and forth intermittently under the drive of the driving device. The forward moving push rod drives the rotating part to rotate around its central axis, and the rotating rotating part drives each claw to rotate through the dial part.

[0009] Preferably, the outer peripheral surface of the rotating member is provided with a plurality of protrusions spaced apart along the circumferential direction, and the protrusions are provided with inclined surfaces inclined relative to the axial direction of the rotating member. The forward moving push rod collides with the inclined surfaces to force the rotating member to rotate around its central axis.

[0010] Preferably, two push rods are provided at intervals along the circumference of the rotating member, the driving device asynchronously drives the two push rods to move forward, and the rotating rotating member drives the push rod released by the driving device to move backward through the inclined surface.

[0011] Preferably, the outer sleeve of the push rod is provided with a reset spring with one end positioned and the other end in contact with the push rod. The push rod moving forward causes the reset spring to be deformed by force. When the push rod is released by the driving device, the reset spring recovers the deformation and drives the push rod to move backward.

[0012] Preferably, the inclination angle θ of the inclined surface relative to the axial direction of the rotating member is 30° to 60°; and / or the push rod is arranged parallel to the ejector pin.

[0013] Preferably, the rotating part includes an inner ring and an outer ring that are sleeved together and rotate synchronously, the protrusion is provided on the outer circumferential surface of the outer ring, the transmission structure is provided between the front end of the inner ring and the rear end of the rotating part, and the inner ring can slide axially relative to the outer ring to engage or disengage the transmission structure.

[0014] Preferably, the transmission structure includes a first transmission tooth provided at the front end of the inner ring and a second transmission tooth provided at the rear end of the dial. The first transmission tooth and the second transmission tooth mesh with each other to enable the inner ring and the dial to be engaged, and the first transmission tooth and the second transmission tooth slip against each other to enable the inner ring and the dial to be separated.

[0015] Preferably, the outer sleeve of the ejector pin is provided with a compression spring with one end abutting against the inner ring and the other end abutting against the ejector pin. The compression spring presses the inner ring against the rotating member, and the forward moving ejector pin causes the compression spring to be deformed by force. When the ejector pin is released by the driving device, the compression spring recovers its deformation and drives the ejector pin to move backward.

[0016] Preferably, the rotating member and the dial member are sleeved on the outer periphery of the front end of the ejector pin, and the tube expander further comprises a support seat and a connecting seat, the support seat is sleeved on the outer periphery of the rear end of the ejector pin, and the connecting seat is sleeved on the inner ring and the outer periphery of the dial member, the support seat cooperates with the connecting seat to limit the rotating member and the dial member axially, and the tube expansion mold is detachably connected to the connecting seat.

[0017] Preferably, the driving device includes a motor, a rotating shaft driven by the motor, a large cam and a small cam sleeved on the rotating shaft, the large cam cooperates with the ejector to drive the ejector to move forward, and the small cam cooperates with the push rod to drive the push rod to move forward.

[0018] After adopting the above technical solution, the utility model has the following advantages:

[0019] 1. The pipe expander provided by the present invention has an intermittent dial assembly including a push rod, a rotating member and a dial assembly. The push rod is driven by a driving device and cooperates with the rotating member. A transmission structure is provided between the rear end of the dial assembly and the rotating member, and an interlocking structure is provided between the front end of the dial assembly and the claw. When the driving device drives the push rod to move forward, the push rod drives the rotating member to rotate around its central axis. The rotating rotating member drives the dial assembly to rotate synchronously through the transmission structure, and the rotating dial assembly drives each claw to rotate synchronously through the interlocking structure. The intermittent dial assembly is reasonably provided to meet the dialing requirements for driving each claw to rotate. There is no need to provide a matching structure for driving the rotating member to rotate between the ejector pin and the intermittent dial assembly. This can reasonably simplify the structure of the ejector pin, avoid the ejector pin from being easily blocked due to the need to drive the rotating member to rotate, and at the same time improve the smoothness of the ejector pin's forward and backward movement and the smoothness of the intermittent dial assembly driving the claw to rotate, which is conducive to improving the user experience.

[0020] 2. The outer circumference of the rotating member is provided with multiple protrusions, each of which is provided with an inclined surface. The inclined surface is arranged at an angle relative to the axial direction of the rotating member. When the push rod moves forward, it contacts the inclined surface of the protrusion. The forward movement of the push rod causes the rotating member to rotate circumferentially due to the contact with the inclined surface. The mating structure between the push rod and the rotating member is properly designed so that the forward movement of the push rod can smoothly drive the rotating member to rotate about its central axis.

[0021] 3. At least two push rods are spaced apart along the axial direction of the rotating member. The driving device asynchronously drives the push rods forward. When the driving device drives one of the push rods forward, the forward-moving push rod causes the rotating member to rotate by contacting the inclined surface. Simultaneously, the rotating member pushes the other push rod backward via the inclined surface on the protrusion to reset. The rational design of the push rod structure reduces structural complexity while meeting the reset requirements of the push rods.

[0022] 4. The push rod can also be reset using a return spring. One end of the return spring is positioned, and the other end contacts the push rod. When the push rod moves forward, the return spring is deformed. When the push rod is released by the driving device, the return spring recovers its deformation and drives the push rod backward to reset. Properly designing the push rod reset method can reduce structural complexity while meeting the push rod reset requirements.

[0023] 5. The angle θ of the inclined plane relative to the axis of the rotating part should be properly set to ensure that the forward-moving push rod can smoothly drive the rotating part through the interference with the inclined plane. The push rod is preferably arranged parallel to the ejector pin, and the distribution relationship between the push rod and the ejector pin is properly set to reasonably simplify the structure of the drive device and reasonably reduce the difficulty of the drive device in driving the push rod and the ejector pin.

[0024] 6. The rotating member adopts a structure combining an inner ring and an outer ring, with a protrusion provided on the outer circumference of the outer ring, and a transmission structure provided between the front end of the inner ring and the rear end of the toggle member. The forward movement of the push rod drives the outer ring to rotate by contact with the inclined surface, and the rotating outer ring drives the inner ring to rotate synchronously. The rotating inner ring can drive the toggle member to rotate through the transmission structure, so that the toggle member drives the claws to rotate through the engaging structure. The inner ring can slide axially relative to the outer ring, so that the transmission structure between the inner ring and the toggle member can be engaged or disengaged. The specific structure of the rotating member is reasonably set, so that the rotating member can not only drive the toggle member to rotate, but also enable the rotating member to achieve clutch with the toggle member.

[0025] 7. The transmission structure is provided between the inner ring and the dial member, and the transmission structure includes a first transmission tooth provided at the front end of the inner ring and a second transmission tooth provided at the rear end of the dial member. When the first transmission tooth and the second transmission tooth engage with each other, the inner ring can drive the dial member to rotate synchronously through the transmission structure, so that the dial member drives the claws to rotate. When the claws of the tube expansion mold are blocked, the first transmission tooth of the inner ring slips relative to the second transmission tooth, and the rotating inner ring cannot drive the dial member to rotate, and thus cannot drive the claws to rotate, and the inner ring is equivalent to idling. The specific structure of the transmission structure is reasonably set so that the transmission structure can be separated in time when the claws are blocked, avoiding the situation where the inner ring forcibly drives the claws to rotate through the dial member, resulting in excessive damage to the bearing capacity, and ensuring the structural stability of the intermittent dial assembly.

[0026] 8. A compression spring is sleeved on the outside of the ejector pin. On the one hand, the compression spring pushes the inner ring against the dial, so that the first transmission tooth and the second transmission tooth are normally in a state of mutual engagement. When the first transmission tooth and the second transmission tooth slip relative to each other, the inner ring can overcome the preload of the compression spring and slide axially, so that the inner ring and the dial can be separated in time, avoiding damage to the pipe expander due to stalling. On the other hand, the forward-moving ejector pin further deforms the compression spring. When the ejector pin is released by the drive device, the compression spring recovers its deformation and drives the ejector pin backward to reset. The matching structure of the compression spring is reasonably set, and the compression spring is used to simultaneously achieve the reset of the ejector pin and the clutch of the transmission structure, so as to meet the structural requirements while reasonably reducing the components of the pipe expander.

[0027] 9. The support seat is mounted on the outer periphery of the rear end of the ejector pin, and the connecting seat is mounted on the outer periphery of the inner ring and the dial. The supporting seat and the connecting seat are used to set the moving components of the tube expander, so that each moving component can move smoothly inside the tube expander. At the same time, the cooperation between the supporting seat and the connecting seat axially limits the rotating member and the dial, ensuring the structural stability of the rotating member and the dial, and thus ensuring that the rotating member can drive the various claws to rotate smoothly through the dial.

[0028] 10. The driving device is provided with a motor, a rotating shaft, a large cam and a small cam. The large cam and the small cam are sleeved on the rotating shaft. The motor drives the rotating shaft to rotate around its central axis. On the one hand, the rotating shaft drives the ejector to move forward through the large cam, and on the other hand, it drives the push rod to move forward through the small cam. Reasonable setting of the specific structure of the driving device can meet the driving requirements of the ejector and the push rod while reasonably simplifying the driving structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a schematic diagram of the entire tube expanding machine of Example 1;

[0030] Figure 2 This is a partial structural diagram of the pipe expanding machine of Example 1 with a pipe expanding die;

[0031] Figure 3 This is a partial structural diagram of the pipe expanding machine in Example 1 when it does not have a pipe expanding die;

[0032] Figure 4 This is a front-to-back cross-sectional view of part of the structure of the pipe expander in Example 1;

[0033] Figure 5 for Figure 4 Enlarged view of point A in the middle;

[0034] Figure 6 An exploded view of part of the structure of the pipe expander in Example 1;

[0035] Figure 7 This is a structural diagram of the tube expanding die in the tube expanding machine of Example 1;

[0036] Figure 8 1 is an axial cross-sectional view of a tube expanding die in a tube expanding machine according to Example 1;

[0037] Figure 9 This is a structural diagram of the ejector pin in the tube expanding machine of Example 1;

[0038] Figure 10 Schematic diagram of the cooperation between the rotating shaft and the large cam in the pipe expanding machine of Example 1;

[0039] Figure 11 This is a structural diagram of the small cam in the pipe expander of Example 1;

[0040] Figure 12 This is a structural diagram of the inner ring of the rotating part in the pipe expanding machine of Example 1;

[0041] Figure 13 This is a structural diagram of the outer ring of the rotating part in the pipe expanding machine of Example 1;

[0042] Figure 14 The structure of the rotating part in the pipe expanding machine of embodiment 1 Figure 1 ;

[0043] Figure 15 The structure of the rotating part in the pipe expanding machine of embodiment 1 Figure 2 ;

[0044] Figure 16 A front-to-back cross-sectional view of a portion of the structure of the tube expander in Example 1 when the ejector pin moves backward into position;

[0045] Figure 17 A front-to-back cross-sectional view of a portion of the structure of the pipe expander in Example 1 when the ejector pin moves forward into position;

[0046] Figure 18 This is a front-to-back cross-sectional view of part of the structure of the pipe expanding machine in Example 2.

[0047] In the figure, 100-tube expansion mold, 110-annular seat, 111-annular groove, 112-internal thread, 120-claw, 121-arc convex edge, 122-second bite block, 130-gathering spring,

[0048] 210-thimble, 211-back plate, 212-lug, 220-pin, 230-roller,

[0049] 300-driving device, 310-motor, 320-rotating shaft, 330-large cam, 331-pushing surface, 332-avoidance surface, 333-transition surface, 340-small cam, 341-protrusion, 350-bearing, 360-positioning sleeve,

[0050] 400-intermittent dial assembly, 410-push rod, 420-rotating member, 421-inner ring, 422-outer ring, 423-protrusion, 424-inclined surface, 425-convex ring, 426-key block, 427-keyway, 428-first transmission tooth, 430-dial member, 431-second transmission tooth, 432-annular protrusion, 433-first bite block, 440-support block, 450-reset spring, 460-gasket,

[0051] 500-case, 510-handle,

[0052] 600-compression spring,

[0053] 710-support seat, 711-slide groove,

[0054] 720-connecting seat, 721-external thread, 722-limiting rib. DETAILED DESCRIPTION

[0055] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. It should be understood that the following terms indicating orientations or positional relationships, such as "upper," "lower," "left," "right," "longitudinal," "lateral," "inner," "outer," "vertical," "horizontal," "top," and "bottom," are based solely on the orientations or positional relationships shown in the accompanying drawings and are intended solely for the purpose of facilitating and simplifying the description of the present invention. They do not indicate or imply that the device or element referred to must have a specific orientation or be constructed or operated in a specific orientation, and therefore should not be construed as limiting the present invention.

[0056] Example 1

[0057] Combine Figures 1 to 17 The pipe expanding machine provided in the first embodiment of the present invention includes:

[0058] The tube expansion die 100 includes a plurality of claws 120 distributed along the circumference and capable of being retracted or expanded;

[0059] The ejector pin 210 driven by the driving device 300, the ejector pin 210 moving forward forces the claw 120 to open, and the ejector pin 210 moving backward releases the claw 120 so that the claw 120 can be retracted;

[0060] The intermittent rotation assembly 400 is used to drive the jaws 120 that have finished opening to rotate around the central axis of the tube expansion die 100;

[0061] The intermittent dial assembly 400 includes a push rod 410 driven by the driving device 300, a rotatable rotating member 420, and a dial member 430 provided between the rotating member 420 and the tube expansion mold 100. The push rod 410 cooperates with the rotating member 420, and a clutch transmission structure is provided between the rear end of the dial member 430 and the rotating member 420. An engaging structure is provided between the front end of the dial member 430 and the claw 120. The push rod 410 can intermittently move back and forth under the drive of the driving device 300. The forward moving push rod 410 drives the rotating member 420 to rotate around its central axis, and the rotating rotating member 420 drives each claw 120 to rotate through the dial member 430.

[0062] The intermittent toggle assembly 400 is reasonably arranged to meet the toggle requirement of driving each claw 120 to rotate. There is no need to set a matching structure between the ejector pin 210 and the intermittent toggle assembly 400 for driving the rotating member 420 to rotate. This can reasonably simplify the structure of the ejector pin 210, avoid the ejector pin 210 from being easily blocked due to the need to drive the rotating member 420 to rotate, and at the same time improve the smoothness of the forward and backward movement of the ejector pin 210 and the smoothness of the intermittent toggle assembly 400 driving the claw 120 to rotate, which is conducive to improving the user experience.

[0063] In this embodiment, the direction in which the ejector pin 210 moves toward the tube expanding die 100 to open the claws 120 is defined as the front direction, and the direction in which the ejector pin 210 moves away from the tube expanding die 100 to close the claws 120 is defined as the rear direction.

[0064] Combine Figure 7 、 Figure 8 In this embodiment, the tube expansion mold 100 further includes an annular seat 110, and the rear end of each clamping claw 120 is connected to the annular seat 110. Specifically, there are six clamping claws 120 in total, and the six clamping claws 120 are arranged one by one along the circumference of the annular seat 110 to form a circle. A circle of annular grooves 111 is provided on the inner wall of the front end of the annular seat 110. The rear end of each clamping claw 120 extends into the front end of the annular seat 110, and the rear end of each clamping claw 120 is provided with an outwardly protruding arcuate ridge 121. The arcuate ridge 121 is embedded in the annular groove 111 to connect the clamping claw 120 to the annular seat 110. The clamping claw 120 is also axially limited by the cooperation between the arcuate ridge 121 and the annular groove 111. An inwardly concave groove is provided on the outer wall of the arcuate ridge 121. A gathering spring 130 is provided at the rear end of the claws 120 to engage with the arcuate ridge 121 to clamp each claw 120. The gathering spring 130 is embedded in the groove on the arcuate ridge 121 and is also located in the annular groove 111 of the annular seat 110. The gathering spring 130 is annular and surrounds the outside of each claw 120. The gathering spring 130 applies a pre-tightening force to the claws 120, causing each claw 120 to be in a retracted state under normal conditions. In the retracted state, the claws 120 are gathered and pressed together, and the front ends of the claws 120 are gathered together to form a tapered head with a maximum outer diameter of D1. When the ejector pin 210 moves forward, forcing each jaw 120 to switch from a closed state to an open state, a gap ring is created between adjacent jaws 120, and the gathering spring 130 is deformed under force, causing the overall outer diameter of the jaws 120 to become D2, where D2>D1. When the ejector pin 210 moves backward, releasing each jaw 120, the gathering spring 130, having recovered its deformation, forces each jaw 120 back from the open state to the closed state. As a preferred embodiment of this embodiment, the tube expanding machine can be configured with multiple tube expanding dies 100 having different maximum outer diameters of the jaws 120 in the closed state, allowing the tube expanding machine to expand pipes of varying diameters. It is understood that the number of jaws 120 in the tube expanding die 100 is not limited to six, and can also be set to three, four, five, seven, eight, or other reasonable numbers. It is also understood that multiple grooves spaced apart front to back can be provided on the outer wall of each jaw 120.

[0065] Combine Figure 1 In this embodiment, the tube expanding machine further comprises a housing 500, wherein the ejector pin 210, the driving device 300, the intermittent rotating assembly 400 and other components are arranged inside the housing 500, and the tube expanding die 100 is located outside the front end of the housing 500. Figure 2 、 Figure 3 、 Figure 6 The drive device 300 includes a motor 310, a rotating shaft 320, and a large cam 330. The motor 310 drives the ejector pin 210 to move forward via the rotating shaft 320 and the large cam 330. In order to appropriately reduce the overall dimensions of the tube expander in the front-to-back direction, the central axis of the motor 310 is roughly aligned with the central axis of the rotating shaft 320, and the axial direction of the rotating shaft 320 is roughly perpendicular to the axial direction of the ejector pin 210, that is, the ejector pin 210 is perpendicular to the rotating shaft 320 and the motor 310. The motor 310 is disposed in the handle 510 formed by the housing 500, and the large cam 330, the ejector pin 210, and the intermittent dial assembly 400 and other components are disposed in the main cavity of the housing 500, so that the overall shape of the tube expander is roughly pistol-shaped. The tube expander of this embodiment can be powered by a battery pack or by connecting a power cord with a plug to the mains. Other structures of the tube expander can refer to existing technologies, such as a switch for controlling the start and stop of the casing 500 and a control panel within the casing 500, and will not be described in detail here. Of course, the motor 310 and the rotating shaft 320 can also be arranged in other ways, such as with the axial direction of the rotating shaft 320 at an angle or perpendicular to the axial direction of the motor 310. The overall shape of the tube expander can also be configured in other reasonable styles based on the distribution of the various components. As an optional solution to this embodiment, a reduction mechanism can be provided between the motor 310 and the rotating shaft 320, or the motor 310 can be a reduction motor.

[0066] The rotating shaft 320 is rotatably mounted in the housing 500 via a bearing 350. The lower end of the rotating shaft 320 is in transmission connection with the output shaft of the motor 310. The large cam 330 is sleeved on the rotating shaft 320. Figure 4 、 Figure 9 The front end of ejector pin 210 is tapered, thicker at the rear and tapering at the front. A roller 230 is attached to the rear end of ejector pin 210 via a pin 220. The outer circumference of a large cam 330 contacts roller 230. The rotating large cam 330 applies force to ejector pin 210 via roller 230, forcing ejector pin 210 forward. In this embodiment, a disc-shaped rear plate 211 is attached to the rear end of ejector pin 210. This rear plate 211 has two rearwardly protruding, opposing lugs 212. Roller 230 is rotatably mounted between the two lugs 212 via a pin 220. The axial direction of roller 230 is roughly parallel to the axial direction of the rotating shaft 320. The ends of the pin 220 are respectively inserted into holes in the two lugs 212. Because roller 230 can rotate circumferentially relative to pin 220, roller 230 can effectively reduce the contact friction between large cam 330 and ejector pin 210, allowing large cam 330 to smoothly drive ejector pin 210 forward. As an alternative to this embodiment, the various components of ejector pin 210 can be integrally formed or separately formed and then fixed together.

[0067] Combine Figure 10 The outer peripheral wall of the large cam 330 is provided with a push surface 331, an avoidance surface 332 and a transition surface 333 which are sequentially distributed along the circumferential direction. Figure 10 Point E in the figure represents the endpoint of the proximal end of the push surface 331, and point F represents the endpoint of the distal end of the push surface 331. The push surface 331 extends from point E to point F along the involute, that is, the push surface 331 is roughly an involute arc surface. Point C represents the central axis of the rotating shaft 320, and ⊙D represents a circle with point C as the center and the distance between point C and point F as the radius. The radial distance between the push surface 331 and the circular contour line shown by ⊙D gradually decreases from point E to point F. Figure 10 Point G in the figure represents the dividing point between the avoidance surface 332 and the transition surface 333. One end of the avoidance surface 332 is smoothly connected to the distal end of the push surface 331, and the other end of the avoidance surface 332 is smoothly connected to the transition surface 333. Both ends of the transition surface 333 are smoothly connected to the proximal ends of the avoidance surface 332 and the push surface 331, respectively. The distance between each point on the avoidance surface 332 and point C is smaller than the distance between point F and point C. The distance between each point on the transition surface 333 and point C gradually increases from point G to point E. When the pipe expander is working, the motor 310 drives the large cam 330 along the rotating shaft 320. Figure 10 When the push surface 331 of the large cam 330 contacts the roller 230, the large cam 330 drives the ejector pin 210 forward through the contact between the push surface 331 and the roller 230. The forward movement of the ejector pin 210 causes each claw 120 to switch from the retracted state to the open state. When the large cam 330 rotates until the avoidance surface 332 contacts the roller 230, the large cam 330 releases the roller 230, and the ejector pin 210 can move backward to reset and release each claw 120. Under the action of the gathering spring 130, each claw 120 can switch from the open state to the retracted state.

[0068] Combine Figure 4 、 Figure 12 、 Figure 13In this embodiment, the push rod 410 is arranged in the housing 500 and can move back and forth through the support block 440. The rotating member 420 includes an inner ring 421 and an outer ring 422 that are sleeved together and rotate synchronously. A plurality of protrusions 423 are provided on the outer peripheral surface of the outer ring 422 and are distributed at intervals along the circumferential direction. The protrusion 423 is provided with an inclined surface 424 that is inclined relative to the axial direction of the rotating member 420. The forward moving push rod 410 contacts the inclined surface 424, causing the outer ring 422 to be forced to rotate around its central axis. The rotating outer ring 422 drives the inner ring 421 to rotate synchronously. In this embodiment, the rotating member 420 is sleeved around the outer circumference of the front end of the ejector pin 210. The inner ring 421 has an inner diameter slightly larger than the outer diameter of the ejector pin 210. The front end of the inner ring 421 is provided with an outwardly protruding collar 425. The outer circumference of the rear end of the inner ring 421 is provided with a plurality of circumferentially spaced and axially extending key blocks 426. The inner circumference of the outer ring 422 is provided with key slots 427 that engage with the key blocks 426. The outer ring 422 is sleeved around the outer circumference of the inner ring 421, with the key blocks 426 embedded in the key slots 427. The collar 425 is located at the front side of the outer ring 422. The engagement of the key blocks 426 and the key slots 427 enables the outer ring 422 to drive the inner ring 421 in synchronous rotation, while also allowing the inner ring 421 to move axially relative to the outer ring. As an alternative to this embodiment, the inclined surface 424 can be a flat surface inclined axially relative to the rotating member 420, or a curved surface inclined tangentially relative to the rotating member 420. As an alternative to this embodiment, the inner ring 421 and the outer ring 422 may also adopt a non-circular shaft-hole matching structure to achieve the purpose of synchronous rotation and relative axial movement.

[0069] In this embodiment, in order to enable the driving device 300 to drive the push rod 410 to move forward, the driving device 300 further includes a small cam 340 sleeved on the rotating shaft 320. Figure 11 The small cam 340 has an outwardly projecting protrusion 341 circumferentially. The small cam 340, which rotates synchronously with the rotating shaft 320, causes the protrusion 341 to contact the rear end of the push rod 410, forcing the push rod 410 forward. In this embodiment, the push rod 410 is arranged parallel to the ejector pin 210 and is positioned between the rotating shaft 320 and the rotating member 420 in the front-to-back direction. To maintain axial stability of the small cam 340, a positioning sleeve 360 can be mounted on the exterior of the rotating shaft 320 to axially position the small cam 340.

[0070] In this embodiment, to enable the push rods 410 to smoothly move backward for reset, two push rods 410 are provided at intervals along the circumference of the rotating member 420. The driving device 300 asynchronously drives the two push rods 410 forward, and the rotating member 420 drives the push rods 410, which have been released by the driving device 300, to move backward via the inclined surface 424. Specifically, the two push rods 41 are provided on the upper and lower sides of the ejector pin 210, respectively. Accordingly, two small cams 340 are provided and respectively sleeved on the upper and lower ends of the rotating shaft 320. The protrusions 341 on the two small cams 340 are staggered along the circumference. When one of the small cams 340 drives one of the push rods 410 forward, causing the push rod 410 to rotate by contacting the inclined surface 424, the rotating member 420, via the other inclined surface 424, contacts the front end of the other push rod 410, forcing the other push rod 410 to move backward for reset.

[0071] In order for push rod 410 to smoothly rotate rotating member 420 to a sufficient degree through the interference with inclined surface 424, inclined surface 424 needs to be reasonably set at an angle θ relative to the axial direction of rotating member 420, preferably 30°≤θ≤60°. In this embodiment, angle θ is approximately 45°. As an alternative to this embodiment, angle θ may also be set to other reasonable values, such as 30°, 35°, 40°, 42°, 48°, 50°, 55°, or 60°.

[0072] Combine Figure 12 、 Figure 14The transmission structure is disposed between the front end of the inner ring 421 and the rear end of the toggle member 430. The inner ring 421 can slide axially relative to the outer ring 422 to engage or disengage the transmission structure. In this embodiment, the toggle member 430 is sleeve-shaped and sleeved around the outer circumference of the front end of the ejector pin 210. The toggle member 430 is located in front of the inner ring 421. The transmission structure includes a first transmission tooth 428 disposed at the front end of the inner ring 421 and a second transmission tooth 431 disposed at the rear end of the toggle member 430. The first transmission tooth 428 and the second transmission tooth 431 engage with each other to drive engagement between the inner ring 421 and the toggle member 430. The first transmission tooth 428 and the second transmission tooth 431 slip against each other to drive disengagement between the inner ring 421 and the toggle member 430. When the first transmission tooth 428 and the second transmission tooth 431 engage with each other, the inner ring 421 can drive the toggle member 430 to rotate synchronously via the transmission structure, thereby causing the toggle member 430 to drive the respective claws 120 to rotate. When the clamping jaws 120 of the tube expansion die 100 become blocked, the first transmission teeth 428 of the inner ring 421 slip relative to the second transmission teeth 431. The rotating inner ring 421 is unable to drive the toggle member 430 to rotate, and thus the clamping jaws 120 to rotate, causing the inner ring 421 to idle. The transmission structure can be disengaged in a timely manner when the clamping jaws 120 become blocked, preventing the inner ring 421 from forcibly driving the clamping jaws 120 through the toggle member 430, which could cause excessive load and easily damage the clamping jaws 120, thereby ensuring the structural stability of the intermittent toggle assembly 400.

[0073] To ensure the transmission structure remains engaged under normal conditions and can be promptly disengaged when the claw 120 becomes blocked, a compression spring 600 is sheathed around the outer portion of the ejector pin 210. The front end of the compression spring 600 contacts the inner ring 421, while the rear end of the compression spring 600 contacts the rear plate 211 of the ejector pin 210. The compression spring 600 forces the inner ring 421 against the toggle 430, keeping the inner ring 421 and the toggle 430 in a normally engaged state. When the inner ring 421 is unable to rotate the claw 120 via the toggle 430, the first transmission teeth 428 slip relative to the second transmission teeth 431. The slipping of the first transmission teeth 428 causes the inner ring 421 to slide backward, overcoming the preload of the compression spring 600. This disengages the inner ring 421 from the toggle 430, allowing the inner ring 421 to rotate idly relative to the toggle 430. When the large cam 330 drives the ejector pin 210 forward through its contact with the roller 230, the rear plate 211 of the ejector pin 210 applies force to the compression spring 600, further deforming it. When the large cam 330 releases the ejector pin 210, the deformed compression spring 600 recovers and drives the ejector pin 210 backward, automatically resetting it. The proper coordination of the compression spring 600 allows it to simultaneously reset the ejector pin 210 and engage / disengage the transmission structure, thereby meeting structural requirements while minimizing the number of components in the pipe expander. In this embodiment, a gasket 460 is provided at the rear end of the inner ring 421, and the front end of the compression spring 600 directly abuts against the gasket 460.

[0074] In this embodiment, the tube expander further comprises a support seat 710 and a connecting seat 720. The support seat 710 is sleeved on the outer periphery of the rear end of the ejector pin 210, and the connecting seat 720 is sleeved on the outer periphery of the inner ring 421 and the rotating member 430. The support seat 710 and the connecting seat 720 cooperate to axially limit the rotating member 420 and the rotating member 430, and the tube expansion mold 100 is detachably connected to the connecting seat 720. Specifically, the support seat 710 is fixed in the housing 500. The rear end of the support seat 710 is provided with two slide grooves 711 distributed vertically and extending in the front-to-back direction. The two ends of the pin rod 220 extend from the lugs 212 and are respectively inserted into the two slide grooves 711. The cooperation between the pin rod 220 and the slide grooves 711 limits the ejector pin 210 in the circumferential direction, thereby preventing the ejector pin 210 from circumferentially rotating during the back-and-forth movement. The connecting seat 720 is fixed to the front end of the housing 500. The front end of the connecting seat 720 extends out of the housing 500 and is provided with an external thread 721 on its outer circumference. The inner circumference of the annular seat 110 in the tube expansion mold 100 is provided with an internal thread 112. The tube expansion mold 100 is detachably connected to the connecting seat 720 through the cooperation of the internal thread 112 and the external thread 721. Figure 5The outer ring 422 of the rotating member 420 is located between the front end surface of the support seat 710 and the rear end surface of the connecting seat 720 in the front-to-back direction, and the outer ring 422 is axially limited by the support seat 710 and the connecting seat 720. The cam 432 is located on the rear side of the second gear 430 and the cam 433 is located on the rear side of the second gear 431.

[0075] Combine Figure 7 、 Figure 15 The interlocking structure includes a first interlocking block 433 provided on the front end surface of the dial 430 and a second interlocking block 122 provided on the rear end surface of each claw 120. A plurality of first interlocking blocks 433 are provided at intervals along the circumference, and a groove for inserting the second interlocking block 122 is formed between two adjacent first interlocking blocks 433. A plurality of second interlocking blocks 122 are provided at intervals along the circumference of the annular seat 110, and a groove for inserting the first interlocking block 433 is formed between two adjacent second interlocking blocks 122. When the tube expansion mold 100 is connected to the connecting seat 720 by threaded fitting, the first interlocking blocks 433 and the second interlocking blocks 122 are staggered and interlocked along the circumference and interlock with each other. The rotating dial 430 drives each claw 120 to rotate around the central axis of the tube expansion mold 100 through the mutually interlocking first interlocking blocks 433 and second interlocking blocks 122.

[0076] Combine Figure 16 、 Figure 17When a pipe needs to be expanded, a pipe expansion die 100 of appropriate size is selected based on the inner diameter of the pipe and installed at the front end of the pipe expander by engaging with the connecting seat 720. When the pipe expander is in operation, the motor 310 drives the rotating shaft 320 to rotate about its central axis. The rotating rotating shaft 320 causes the large cam 330 and the small cam 340 to rotate synchronously. The rotating large cam 330, through the interference with the roller 230, drives the ejector pin 210 to move forward, overcoming the preload force of the compression spring 600. The forward movement of the ejector pin 210 compresses the compression spring 600 and forces the claws 120 to open outward. The opened claws 120 force the ends of the pipe to open. After the ejector 210 moves forward to its position, the large cam 330 releases the ejector 210. The claws 120 stop opening when the large cam 330 releases the ejector 210. The compression spring 600 that recovers the deformation drives the ejector 210 to move backward for reset. The backward moving ejector 210 releases the claws 120, and the claws 120 gradually close under the action of the gathering spring 130. As the compression spring 600 forces the ejector pin 210 to move backward and reset, one of the small cams 340, rotating synchronously with the rotating shaft 320, forces one of the push rods 410 forward. The forward movement of the push rod 410, through the interfering engagement with the inclined surface 424, drives the outer ring 422 to rotate about its central axis. The rotating outer ring 422 then rotates the inner ring 421 synchronously. The rotating inner ring 421, through the engagement of the first transmission teeth 428 and the second transmission teeth 431, drives the toggle 430 to rotate. The rotating toggle 430, through the interlocking structure, rotates each of the claws 120 a certain angle. Simultaneously, the rotating outer ring 422, through the interfering engagement with the front end of the other push rod 410 via the other inclined surface 424, forces the other push rod 410 backward, resets it, and resets it. Once the ejector pin 210 has reached its desired position, the large cam 330 can again drive the ejector pin 210 forward, opening each of the claws 120 for tube expansion.

[0077] When the claw 120 is stuck and cannot be driven by the toggle 430 to rotate smoothly, the toggle 430 cannot rotate circumferentially. At this time, the rotating inner ring 421 causes the first transmission tooth 428 to slip relative to the second transmission tooth 431, and the inner ring 421 is disengaged from the toggle 430. The idling inner ring 421 cannot drive the toggle 430 to rotate, but the ejector 210 can still move back and forth normally. When the situation is resolved, the inner ring 421 moves forward under the bias of the compression spring 600 to reset the first transmission tooth 428 to a state where it is again in transmission engagement with the second transmission tooth 431.

[0078] Example 2

[0079] Combine Figure 18In order to allow the push rod 410 to move backward and reset, in this embodiment, a return spring 450 is sleeved on the outside of the push rod 410, with one end positioned and the other end contacting the push rod 410. The push rod 410 moving forward causes the return spring 450 to deform under force. When the push rod 410 is released by the small cam 340, the return spring 450 recovers its deformation and drives the push rod 410 to move backward and reset. Specifically, only one push rod 410 can be provided, and correspondingly, only one small cam 340 can be provided. The front end of the return spring 450 contacts the support block 440 for positioning, and the rear end of the return spring 450 contacts the protrusion at the rear end of the push rod 410 for contacting the push rod 410. When the small cam 340 drives the push rod 410 to move forward, causing the push rod 410 to push the rotating member 420 to rotate circumferentially, the return spring 450 is compressed. When the small cam 340 releases the push rod 410, the return spring 450 recovers its deformation and drives the push rod 410 to move backward to reset.

[0080] In this embodiment, in order to ensure that the push rod 410 moving forward can stably push the rotating part 420 to rotate circumferentially, two push rods 410 can also be set, and a return spring 450 is set on the outside of each push rod 410. At this time, the two small cams 340 mounted on the rotating shaft 320 can drive the two push rods 410 to move forward synchronously.

[0081] The other structures of the second embodiment are the same as those of the first embodiment and will not be described in detail here.

[0082] In addition to the above preferred embodiments, the present invention has other implementation methods. Those skilled in the art can make various changes and modifications based on the present invention. As long as they do not depart from the spirit of the present invention, they should all fall within the scope defined in the claims of the present invention.

Claims

1. Tube expanding machine, including: The tube expansion die comprises a plurality of claws distributed along the circumference and capable of being retracted or expanded; The ejector is driven by a driving device. The forward movement of the ejector forces the jaws to open, while the backward movement of the ejector releases the jaws so that they can be retracted. An intermittent rotating assembly is used to drive the jaws that have finished opening to rotate around the central axis of the tube expansion die; It is characterized in that The intermittent dial assembly includes a push rod driven by a driving device, a rotatable rotating part, and a dial part provided between the rotating part and the pipe expansion mold. The push rod and the rotating part cooperate with each other, and a clutch transmission structure is provided between the rear end of the dial part and the rotating part. An engaging structure is provided between the front end of the dial part and the claw. The push rod can move back and forth intermittently under the drive of the driving device. The forward moving push rod drives the rotating part to rotate around its central axis, and the rotating rotating part drives each claw to rotate through the dial part.

2. The pipe expanding machine according to claim 1, characterized in that The outer circumferential surface of the rotating member is provided with a plurality of protrusions distributed at intervals along the circumferential direction. The protrusions are provided with inclined surfaces inclined relative to the axial direction of the rotating member. The forward moving push rod contacts the inclined surfaces to force the rotating member to rotate around its central axis.

3. The pipe expanding machine according to claim 2, characterized in that: Two push rods are arranged at intervals along the circumference of the rotating member. The driving device asynchronously drives the two push rods to move forward, and the rotating rotating member drives the push rod released by the driving device to move backward through the inclined surface.

4. The pipe expanding machine according to claim 2, characterized in that The outer sleeve of the push rod is provided with a return spring with one end positioned and the other end in contact with the push rod. The push rod moving forward causes the return spring to be deformed by force. When the push rod is released by the driving device, the return spring recovers the deformation and drives the push rod to move backward.

5. The pipe expanding machine according to claim 2, characterized in that: The inclination angle θ of the inclined surface relative to the axial direction of the rotating member is 30° to 60°; and / or the push rod is arranged parallel to the ejector pin.

6. The pipe expanding machine according to claim 2, characterized in that The rotating part includes an inner ring and an outer ring that are sleeved together and rotate synchronously. The protrusion is provided on the outer circumferential surface of the outer ring. The transmission structure is provided between the front end of the inner ring and the rear end of the rotating part. The inner ring can slide axially relative to the outer ring to engage or disengage the transmission structure.

7. The pipe expanding machine according to claim 6, characterized in that The transmission structure includes a first transmission tooth arranged at the front end of the inner ring and a second transmission tooth arranged at the rear end of the dial. The first transmission tooth and the second transmission tooth mesh with each other to enable the inner ring and the dial to be engaged in transmission, and the first transmission tooth and the second transmission tooth slip against each other to enable the inner ring and the dial to be separated in transmission.

8. The pipe expanding machine according to claim 6, characterized in that The outer sleeve of the ejector pin is provided with a compression spring with one end abutting against the inner ring and the other end abutting against the ejector pin. The compression spring presses the inner ring against the rotating member. The forward moving ejector pin deforms the compression spring under force. When the ejector pin is released by the driving device, the compression spring recovers its deformation and drives the ejector pin to move backward.

9. The pipe expanding machine according to claim 6, characterized in that The rotating part and the dial part are sleeved on the outer periphery of the front end of the ejector pin. The tube expanding machine also includes a support seat and a connecting seat. The support seat is sleeved on the outer periphery of the rear end of the ejector pin. The connecting seat is sleeved on the inner ring and the outer periphery of the dial part. The support seat cooperates with the connecting seat to limit the rotating part and the dial part axially. The tube expanding mold is detachably connected to the connecting seat.

10. The pipe expanding machine according to claim 1, characterized in that The driving device includes a motor, a rotating shaft driven by the motor, a large cam and a small cam sleeved on the rotating shaft. The large cam cooperates with the ejector to drive the ejector forward, and the small cam cooperates with the push rod to drive the push rod forward.

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