CN103357770B - Expansion head assembly - Google Patents

Abstract

The present invention relates to an expansion head assembly, which includes an expansion head fixed shaft and an expansion ball. The expansion ball is installed on the expansion head fixed shaft through a locking structure composed of an expansion sleeve and an expansion head pin. The expansion sleeve is hollow and has an insertion end with a groove extending through its peripheral wall along its axial direction. The expansion head fixed shaft has an axial center hole. The inner peripheral wall of the center hole and the outer wall of the elastic sheet are provided with a first snap-fit structure. The insertion end is inserted into the center hole to install the expansion sleeve on the expansion head fixed shaft through the first snap-fit structure. The expansion head pin has an expansion head pin cap and an expansion head pin body. The peripheral wall of the expansion head pin body near the end and the inner peripheral wall of the elastic sheet near the end are provided with a second snap-fit structure. The expansion head pin body passes through the expansion ball through-hole to install the expansion ball on the expansion head fixed shaft through the second snap-fit structure. The present invention utilizes the expansion sleeve insertion end with radial deformation capability and the snap-fit structure to conveniently install the expansion ball on the expansion head fixed shaft, providing a connection structure that is different from the current expansion ball and expansion rod, and has a simple structure.

Description

A kind of expansion head assembly

(1) Technical field

The invention relates to an expanding head assembly.

(2) Background technology

The tube expansion process is a process in which the tube expansion tool is squeezed into the copper tube by an external force to expand the diameter of the steel tube. The tube expansion tool is generally composed of an expansion rod and an expansion ball installed on the expansion rod with a diameter larger than the inner diameter of the steel pipe. There are currently two ways to connect the rod and the expansion ball, one is welding, but welding is not conducive to the replacement of the expansion ball, because it is necessary to replace different types of expansion balls when expanding pipes with different diameters and specifications, or to expand during use. The ball is easily damaged and needs to be replaced. The other is as described in ZL2010102210735, which uses a threaded structure to connect to realize the replacement of the expanding ball. It is described in the text that the expanding head includes the expanding tip and the expanding ring (that is, the expanding ball) set on the expanding tip. The expanding tip and the front The connecting rods are threaded.

However, there are also shortcomings in the threaded structure connection method, because the axial force generated during the expansion process is borne by the threaded structure, especially for the expansion rod with a small diameter, the thread structure is easily damaged, which will cause the expansion of the ball and the expansion rod. The central axis of the tube is not aligned or the thread structure fails and the thread slips, which affects the effect of tube expansion or damages the tube expansion tool.

(3) Contents of the invention

The purpose of the present invention is to provide an expansion head assembly, which makes the connection mode of the expansion ball and the expansion rod different from the above two structures, and the structure is simple and easy to install.

To achieve the above object, the present invention adopts the following technical solutions:

An expansion head assembly, including an expansion head fixing shaft and an expansion ball, the center of the expansion ball is provided with an expansion ball through hole, characterized in that the expansion ball is installed on the expansion head fixing shaft through a locking structure, and the locking structure includes Expansion sleeve and expansion head pin; the expansion sleeve is a hollow cylindrical structure and has an insertion end. The insertion end is provided with a slit through its peripheral wall along its axial direction. The slit divides the insertion end into a number of radially arranged Elastic sheet deformed in the direction; one end of the expansion head fixing shaft is provided with an axial central hole, and the inner peripheral wall of the central hole and the outer wall of the elastic sheet are provided with a corresponding first buckle structure, and the insertion end is inserted into the center The expansion sleeve is installed on the fixed shaft of the expansion head through the first buckle structure; the expansion pin has an expansion pin cap and an expansion pin body connected with the expansion pin cap, and the expansion pin body is near the end The surrounding wall and the inner peripheral wall near the end of the elastic sheet are provided with a corresponding second buckle structure. After the expansion head pin body passes through the through hole of the expansion ball, the expansion ball is installed on the expansion head fixed shaft through the second buckle structure. , the expansion head pin cap bears against the front end of the expansion ball.

The present invention utilizes the buckle structure and the radial deformability of the insertion end of the expansion sleeve to conveniently install the expansion ball on the expansion head fixing shaft, and provides a method that is different from the currently existing expansion balls and expansion head fixing shafts (also available) It is an expansion rod) connection structure, and the structure is simple.

The present invention can be improved by following scheme:

The first buckle structure includes a first chute ring and a first stop protrusion ring, the first chute ring is circumferentially arranged at the end of the outer wall of the elastic sheet, and the first stop protrusion ring Circumferentially arranged on the wall of the central hole, the first stop protrusion ring can be snapped into the first chute ring, and the first stop protrusion ring is provided with an inclined first guide on one side of the central hole. lead department. When the end of the insertion end of the expansion sleeve first passes through the area of the first stop protrusion ring, the insertion end smoothly passes through the first stop protrusion due to the radial inward contraction of the elastic piece by the extrusion of the first stop protrusion ring Ring area, after passing through this area, the self-elasticity of the elastic piece returns to the original state, and the expansion sleeve can be installed on the expansion head fixed shaft through the engagement of the first chute ring and the first stopper ring . Wherein the provision of the first guide part can make the insertion end of the expansion sleeve pass through the first stop protrusion ring area more conveniently.

The end of the outer wall of the insertion end of the expansion sleeve is provided with an inclined second guide portion. Setting the second guide part can also facilitate the insertion end of the expansion sleeve to more easily enter the central hole of the expansion head fixed shaft.

The first chute ring separates the insertion end of the expansion sleeve into a first annular protrusion away from the end and a second annular protrusion located at the end, the outer peripheral surface of the first annular protrusion is in contact with the central hole Inner wall fit. The expansion sleeve is coaxial with the expansion head fixing shaft through the fit between the outer peripheral surface of the first annular protrusion and the inner wall surface of the central hole.

The second buckle structure includes a second chute ring and a second stop protrusion ring, the second chute ring is circumferentially arranged at the end of the expander pin body, and the second stop protrusion ring is It is arranged near the end of the inner wall of the expansion sleeve insertion end, and the second stop protrusion ring can be snapped into the second slide groove ring. When the expansion pin body enters the expansion sleeve, first rely on the expansion pin body to stretch the elastic piece at the insertion end radially outward to facilitate its entry. When the second stopper ring snaps into the second chute ring, The elastic sheet returns to its original state by its own elastic action, and the body of the expanding head pin is limited in the axial direction. At the same time, the elastic sheet cannot Elastic deformation occurs radially inward, so the expansion sleeve cannot be disengaged from the expansion head fixing shaft before the expansion pin body is detached.

An inclined third guide part is provided between the second stop protrusion ring and the second sliding groove ring near the end of the expansion pin body, and the outer peripheral surface of the second annular protrusion is in contact with the central hole. There is a gap on the inner wall surface, which is larger than the radial distance required for the second stopper ring to break away from the second chute ring. The three guide parts elastically deform the elastic sheet radially outward so that the expansion pin is detached from the expansion sleeve against the action of the second buckle structure. The elastic sheet is deformed by setting the third guide part and the gap so that the expansion pin body and the expansion sleeve are separated in the axial direction, thereby facilitating the replacement of the expansion ball.

Between the other end of the expanding sleeve opposite to the inserting end and the expanding ball, there is a first radially extruded guiding portion for a wedge-shaped tool to enter to force the expanding pin and the expanding sleeve to move away from each other in the axial direction. After the wedge-shaped tool enters the first radial extrusion guide part, its wedge-shaped structure can convert a small radial force into a large axial extrusion force, so that the expansion pin body and the expansion sleeve can be easily connected axially separated.

The other end of the expansion sleeve opposite to the insertion end is provided with an expansion sleeve cap whose outer diameter is larger than the diameter of the central hole and smaller than the outer diameter of the fixed shaft of the expansion head, and the first radial extrusion guide part is arranged on the expansion sleeve cap and the expansion ball between. The expansion sleeve is provided with an expansion sleeve cap to facilitate the extraction of the expansion sleeve from the central hole.

A second radially extruded guide portion is provided between the expansion pin cap and the expansion ball, through which a wedge-shaped tool enters to force the expansion pin and the expansion sleeve to move away from each other in the axial direction. After the wedge-shaped tool enters the second radial extrusion guide part, its wedge-shaped structure can convert a small radial force into a large axial extrusion force, so that the expansion pin body and the expansion sleeve can be easily connected axially separated.

The front end of the expander pin cap is a conical guiding tapered surface, which is convenient for the expander assembly to smoothly enter the copper tube for tube expansion during tube expansion.

(4) Description of drawings

Fig. 1 is the schematic diagram of the assembled state of the present invention;

Fig. 2 is the schematic diagram of the decomposition state of the present invention;

Fig. 3 is a sectional view of the present invention (expansion sleeve does not have expansion sleeve cap in this figure);

Fig. 4 is a schematic sectional view of the present invention entering the copper tube when expanding the tube;

Fig. 5 is a schematic sectional view of the present invention withdrawing from the copper tube after expanding the tube;

Fig. 6 is a cross-sectional schematic diagram of a wedge-shaped tool entering the first radial extrusion guide part to force the expansion pin and the expansion sleeve to deviate from each other in the axial direction, and the insertion end elastically deforms radially outward;

Fig. 7 is a cross-sectional schematic diagram of a wedge-shaped tool entering the second radial extrusion guide part to force the expansion pin and the expansion sleeve to deviate from each other in the axial direction, and the insertion end elastically deforms radially outward;

FIG. 8 is an enlarged schematic view of A in FIG. 5 .

Explanation of reference signs:

10- expansion head fixed shaft;

11-central hole; 11-10 the first stop raised ring; 11-11 the first guide part; 11-12 the fourth guide part;

20-bulging ball;

21-expansion ball through hole; 22-expansion ball front end face;

30-expansion sleeve;

31-insert end; 31-1 split groove; 31-2 first chute ring; 31-3 second guide part; 31-4 first annular protrusion; 31-5 second annular protrusion; 31-6 The second stop raised ring; 31-6-1 third guide;

32-Expansion sleeve cap; 32-1 The first radial extrusion guide part

40-Expansion head pin

41-expansion head pin cap;

42-expansion head pin body; 42-1 second chute ring;

50 - Wedge tool. the

(5) Specific implementation methods

An expansion head assembly as shown in Figures 1 and 2, includes an expansion head fixing shaft 10 and an expansion ball 20, the expansion ball 20 is installed on the expansion head fixing shaft 10 through a locking structure, and the locking structure includes an expansion sleeve 30 and expansion pin 40.

The center of the expansion ball 20 is provided with an expansion ball through hole 21 .

The expansion sleeve 30 is a hollow cylindrical structure and has an insertion end 31. The insertion end 31 is provided with a split groove 31-1 passing through its peripheral wall along its axial direction. The split groove 31-1 divides the insertion end 31 into several circumferentially arranged radially deformable elastic sheet.

One end of the expansion head fixing shaft 10 is provided with an axial central hole 11, and the inner peripheral wall of the central hole 11 and the outer wall of the elastic sheet are provided with a corresponding first buckle structure.

The expander pin 40 has an expander pin cap 41 and an expander pin body 42 connected to the expander pin cap 41, and the peripheral wall near the end of the expander pin body 42 and the inner peripheral wall near the end of the elastic sheet are provided with corresponding The corresponding second buckle structure.

The insertion end 31 is first inserted into the central hole 11 and the expansion sleeve 30 is installed on the expansion head fixed shaft 10 through the first buckle structure, and then the expansion head pin body 42 passes through the expansion ball through hole 21 and passes through the second The buckle structure installs the expansion ball 20 on the fixed shaft 10 of the expansion head, and the expansion head pin cap 41 pushes against the front end surface 22 of the expansion ball.

The invention utilizes the radial deformability of the insertion end of the expansion sleeve and the buckle structure to conveniently install the expansion ball on the fixed shaft of the expansion head, which is different from the existing connection structure of the expansion ball and the expansion rod, and has a simple structure.

The further improvements made in the structure of the expander assembly will be described below in conjunction with accompanying drawings 3 to 8 .

The first buckle structure includes a first chute ring 31-2 and a first stop protrusion ring 11-10, and the first chute ring 31-2 is circumferentially arranged at the end of the outer wall of the elastic sheet , the first stop protrusion ring 11-10 is circumferentially arranged on the wall of the central hole 11, and the first stop protrusion ring 11-10 can be snapped into the first chute ring 31-2, The first stop protruding ring 11-10 is provided with an inclined first guide part 11-11 on the side close to the opening of the central hole 11. Of course, the first stop protruding ring 11-10 can be arranged on the elastic sheet of the expansion sleeve 30 The outer wall is close to the end, and the first chute ring 31-2 can be arranged on the wall of the central hole 11, and the same effect can also be achieved by performing an exchange. When the end of the insertion end of the expansion sleeve passes through the area of the first stop protrusion ring 11-10, the insertion end shrinks radially inward due to the extrusion of the elastic piece by the first stop protrusion ring 11-10 and passes through this area smoothly , after passing through this area, the elastic sheet returns to its original state by its own elastic action, and the expansion sleeve can be installed on the expansion head through the engagement of the first chute ring 31-2 and the first stop protrusion ring 11-10 fixed on the shaft. Wherein the first guide portion 11-11 is provided so that the insertion end 31 of the expansion sleeve 30 can pass through the first stop protrusion ring 11-10 area more conveniently.

The end of the outer wall of the insertion end 31 of the expansion sleeve 30 is provided with an inclined second guide portion 31-3. The provision of the second guide portion 31 - 3 can also facilitate the insertion end 31 of the expansion sleeve 30 to enter into the central hole of the fixed shaft of the expansion head more conveniently.

The first chute ring 31-2 separates the insertion end 31 of the expansion sleeve 30 into a first annular protrusion 31-4 away from the end and a second annular protrusion 31-5 located at the end. The outer peripheral surface of the annular protrusion 31 - 4 is in contact with the inner wall surface of the central hole 11 . The outer peripheral surface of the first annular protrusion 31 - 4 fits with the inner wall surface of the central hole 11 to make the expansion sleeve and the expansion head fixed axis coaxial.

The second buckle structure includes a second sliding groove ring 42-1 and a second stop protrusion ring 31-6, and the second sliding groove ring 42-1 is circumferentially arranged at the end of the expansion pin body 42 , the second stop protrusion ring 31-6 is circumferentially arranged at the end of the inner wall of the insertion end 31 of the expansion sleeve 30, and the second stop protrusion ring 31-6 can be snapped into the second chute ring 42-1, of course, the second stop protrusion ring 31-6 can be placed near the end of the expansion head pin body 42, and the second chute ring 42-1 can be set at the insertion end of the expansion sleeve 30 The 31 inner walls are close to the end, that is to say, the same effect is also achieved by reverse adjustment. When the expansion pin body 42 enters the expansion sleeve, the elastic piece at the insertion end is stretched radially outward by the expansion pin body to facilitate its entry. When the second stopper ring 31-6 snaps into the second The chute ring, the elastic piece returns to the original state by its own elastic action, and the expansion pin body is limited in the axial direction. At the same time, because the second stop protrusion ring 31-6 snaps into the second chute The ring prevents the elastic sheet from being elastically deformed radially inward, so the expansion sleeve cannot be disengaged from the expansion head fixing shaft before the expansion pin body is detached.

As shown in FIG. 8 , an inclined third guide portion 31 - 6-1, and there is a gap h ₁ between the outer peripheral surface of the second annular protrusion 31-5 and the inner wall surface of the central hole 11, which is larger than the second stopper ring 31-6 when it is separated from the second chute ring 42 -1 the required radial distance h ₂ , when the expansion sleeve 30 and the expansion pin 40 deviate from each other in the axial direction, the expansion pin body 42 makes the elastic piece radially The outer elastic deformation makes the expansion pin 40 detach from the expansion sleeve 30 against the action of the second buckle structure. The expansion pin body 42 is separated from the expansion sleeve 30 in the axial direction by setting the third guide portion 31 - 6 - 1 and the gap to deform the elastic sheet, thereby facilitating the replacement of the expansion ball 20 .

The other end of the expansion sleeve 30 opposite to the insertion end 31 and the expansion ball 20 is provided with a first radial extrusion guide for the wedge-shaped tool 50 to enter and force the expansion pin 40 to deviate from the expansion sleeve 30 in the axial direction. Part 32-1, as shown in FIG. 6 . After the wedge-shaped tool 50 enters the first radial extrusion guide part 32-1, its wedge-shaped structure can convert a small radial force into a large axial extrusion force, so that the expansion pin body can be easily 42 is separated from the expansion sleeve 30 in the axial direction. The other end of the expansion sleeve 30 relative to the insertion end 31 is provided with an expansion sleeve cap 32 whose outer diameter is larger than the diameter of the central hole 11 and smaller than the outer diameter of the expansion head fixed shaft 10. Of course, the outer diameter of the expansion sleeve cap 32 is also smaller than the expansion ball The maximum outer diameter of the expansion sleeve 30 is provided to prevent the expansion sleeve cap 32 from contacting the pipe wall when the tube is expanded. The above-mentioned first radial extrusion guide part 32-1 can be arranged between the expansion sleeve cap 32 and the expansion ball 20. In fact, in order to separate the expansion head pin body 42 from the expansion sleeve 30 in the axial direction, it is also necessary to The above-mentioned first radial extrusion guide part 32-1 can be changed into a wedge-shaped tool 50 provided between the expansion pin cap 41 and the expansion ball 20 to force the expansion pin 40 and the expansion sleeve 30 to be in the axial direction. The second radially extruding guiding part deviates upward, as shown in FIG. 7 . After the wedge-shaped tool 50 enters the second radial extrusion guide part, its wedge-shaped structure can convert a small radial force into a large axial extrusion force, and can also easily connect the expansion pin body 42 with the The expansion sleeve 30 is separated axially.

It is worth mentioning that, in the process of tube expansion, although the expansion ball 20 will be affected by the action of the steel pipe wall, the expansion pin 40 will have a tendency to axially separate from the expansion sleeve 30, but according to the actual use situation, the The above force is not enough to separate the expansion pin 40 from the expansion sleeve 30 in the axial direction. As shown in Figure 4 or Figure 8, an inclined fourth guide part 11-12 is provided on the side of the first stopper protrusion ring 11-10 away from the opening of the central hole 11, and the fourth guide part can also be arranged on When the second annular protrusion is assembled, it faces the side of the first stop protrusion ring 11-10, or both of them are arranged correspondingly, so that when in use, the fourth guide part can press the second annular protrusion The function of 31-5 (that is, to play the role of squeezing the elastic sheet so that the elastic sheet grasps the expansion pin radially inward) prevents the expansion pin 40 from being separated from the expansion sleeve 30 in the axial direction. After the expansion head pin 40 is pulled out during disassembly, the fourth guide part 11 - 12 plays the role of facilitating the separation of the expansion sleeve 30 from the expansion head fixing shaft 10 .

Because of the existence of the fourth guide portion 11-12, if the first buckle structure is tightly fitted on the shaft (there is no gap between the first stop protrusion ring 11-10 and the first chute ring 31-2 shaft), it will When the expansion pin 40 is to be axially separated from the expansion sleeve 30, the fourth guide part presses the second annular protrusion 31-5, so that the axial separation of the expansion pin 40 and the expansion sleeve 30 cannot be realized, so the first There is a gap between the stop protrusion ring 11-10 and the first chute ring 31-2, so that when the expansion pin 40 is axially separated from the expansion sleeve 30, the second annular protrusion 31-5 is far away from the first Stop protrusion ring 11-10, as shown in Figure 4, Figure 6 and Figure 7.

The above-mentioned embodiment is a preferred embodiment of the present invention, but the embodiment of the present invention is not limited thereto, and any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention are equivalent All replacement methods are included within the protection scope of the present invention.

Claims (10)

1. An expansion head assembly, comprising an expansion head fixed shaft and an expansion ball, the middle of the expansion ball is provided with an expansion ball through hole, it is characterized in that: the expansion ball is installed on the expansion head fixed shaft through a locking structure, and the locking The structure includes expansion sleeve and expansion pin; The expansion sleeve is a hollow cylindrical structure and has an insertion end, and the insertion end is provided with a slit through its peripheral wall along the axial direction, and the slit divides the insertion end into several radially deformable elastic pieces arranged in the circumferential direction; One end of the expansion head fixing shaft is provided with an axial central hole, the inner peripheral wall of the central hole and the outer wall of the elastic sheet are provided with a corresponding first buckle structure, the insertion end is inserted into the central hole and passed through the first The buckle structure installs the expansion sleeve on the fixed shaft of the expansion head; The expander pin has an expander pin cap and an expander pin body connected to the expander pin cap, and the peripheral wall near the end of the expander pin body and the inner peripheral wall near the end of the elastic sheet are provided with corresponding second clips. Buckle structure, the expansion head pin body passes through the expansion ball through hole and installs the expansion ball on the expansion head fixed shaft through the second buckle structure, and the expansion head pin cap pushes against the front end of the expansion ball. 2. The expansion head assembly according to claim 1, characterized in that: the first buckle structure includes a first sliding groove ring and a first stop protrusion ring, and the first sliding groove ring is circumferentially It is arranged near the end of the outer wall of the elastic sheet, and the first stop protrusion ring is circumferentially arranged on the wall of the central hole, and the first stop protrusion ring can be snapped into the first chute ring, An inclined first guide portion is provided on one side of the first stop protrusion ring near the central opening. 3. An expansion head assembly according to any one of claims 1 or 2, characterized in that: the end of the outer wall of the insertion end of the expansion sleeve is provided with an inclined second guide portion. 4. An expander assembly according to claim 2, characterized in that: the first sliding groove ring separates the insertion end of the expander into a first annular protrusion far away from the end and a second annular protrusion located at the end. An annular protrusion, the outer peripheral surface of the first annular protrusion is attached to the inner wall surface of the central hole. 5. An expanding head assembly according to any one of claims 1, 2 and 4, characterized in that: the second buckle structure includes a second slide groove ring and a second stop protrusion ring, and the second slide The groove ring is arranged at the end of the expander pin body in the circumferential direction, and the second stop protrusion ring is arranged at the end of the inner wall of the expansion sleeve insertion end in the circumferential direction, and the second stop protrusion ring can be snapped into Inside the second sliding groove ring. 6. The expander assembly according to claim 5, characterized in that: an inclined first stop is provided between the second stop protrusion ring and the second chute ring on the side close to the end of the expander pin body. Three guide parts, and there is a gap between the outer peripheral surface of the second annular protrusion and the inner wall surface of the central hole, the gap is greater than the radial distance required for the second stopper ring to break away from the second sliding groove ring, and the expansion sleeve When the expansion pin is away from the axial direction, the expansion pin body elastically deforms the elastic piece radially outward through the third guide part, so that the expansion pin is detached from the expansion sleeve against the action of the second buckle structure. 7. An expansion head assembly according to claim 6, characterized in that: between the other end of the expansion sleeve opposite to the insertion end and the expansion ball, a wedge-shaped tool is provided to force the expansion pin and the expansion sleeve to be aligned on the shaft. The first radial extrusion guides diverge upward. 8. An expansion head assembly according to claim 7, characterized in that: the other end of the expansion sleeve opposite to the insertion end is provided with an expansion sleeve cap whose outer diameter is larger than the diameter of the central hole and smaller than the outer diameter of the expansion head fixing shaft , the first radial extrusion guide part is arranged between the expansion sleeve cap and the expansion ball. 9. An expansion head assembly according to claim 6, characterized in that: a wedge-shaped tool is provided between the expansion head pin cap and the expansion ball to force the expansion head pin and the expansion sleeve to align in the axial direction. The diverging second radial extrusion guide. 10 . The expansion head assembly according to claim 9 , wherein the front end of the expansion head pin cap is a conical guiding tapered surface. 11 .