JPH0679356A - In-line roller type pipe bending machine - Google Patents

Abstract

PURPOSE: To continue bending operation without causing wrinkle circulation by rotatably placing deformation rollers on a flange rotatably supported by a bending arm. CONSTITUTION: An inner die 50 includes a circumferential groove 51 following the shape of a part 52 to be bent, the part 52 is a cylindrical pipe, the cross section of the groove 51 is set to about half the circumference of the pipe. The inner die 50 is operated in cooperation with an outer die 53, the outer die 53 is composed of at least two means exerting the pressure on the part 52, and the means for exerting the pressure is set as rollers 54. The rollers 54 are provided in a shaft rotation pedestal 55, and the pedestal 55 is rotated around a shaft 56. The rollers 54 are provided with a recessed circumferential groove, adapting to the cross section of the part to be bent. Since the pedestal 55 is rotated around the shaft, the reaction exerting on a first roller 57 is transmitted to a second roller 58 locating in a bending position. The reaction acts so that the pipe existing in the bending position is completely housed into the inner die 50. Thus, the bending position timing is will not lag behind that of the highest pressure position.

Description

Detailed Description of the Invention

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tube bending machine, and more particularly to an apparatus and method for bending a tube using at least two means for exerting pressure on an inner mold.

2. Description of the Related Art Although many devices for bending pipes are known,
Each has its own usage and limitations. There are usually unacceptable features in the curved portion of the tube. This twisting of the surface of the component is usually found inside the curved portion and is considered to be the main defect. Wrinkles on the surface of this component are also usually found inside the bend. The wrinkles are small but continuous kinks, often unacceptable. Flat deformations are seen on the outside of the bend in the cross-sectional figure, but are sometimes acceptable if they are visually less noticeable. Although scratches, dents, and bulges on the surface of the component due to the bending device are considered to be defects which are usually not so important from a mechanical point of view,
Perhaps very important in terms of aesthetics. Recently, tubes and RHS have come to use C350 grade steel, which is stronger than previously used steel. This grade of steel hardens as it is cold formed into a tube. Also, seams are welded by electric resistance welding. Completed pipe and RH
S is tough and quite resistant to deformation. However, subjecting to bending is itself a controlled deformation. Furthermore, regarding parts, thin walls are being used to obtain parts that are lighter in weight than conventional parts but of equal strength. While strong, thin and lightweight parts are convenient for most users, when using traditional bending equipment for parts made by conventional methods, one encounters problems including all of the bending drawbacks described above. Most existing tube bending machines control the part cross section and bend radius,
It uses a solid curved type. One of the simpler types of bending machines uses two fixed columns to provide a reaction, with the inner mold being pressed between the columns to the pipe component to create the bend. As the mold steps forward between the columns, the bend begins to be made from the center and progresses in both directions along the part. This type of bender is commonly referred to as a "fixed column bender". The large reaction area (to allow the mold to move between columns) allows it to be easily bent with relatively small feed forces. However, a high mold contact pressure is desirable to prevent wrinkles in the bend, especially in the C350 grade parts used today. Severe kinking usually occurs in C350 grade tubes in the traditional mold with a radius of curvature of about three times the tube diameter. Attempts have been made to avoid this by increasing the mold radius from three times the diameter to four times the diameter, and by bringing the mold closer to the mold to the extent that it is pressed into the mold. No kinks are created because the grooves in the mold prevent the tube from coming out of the mold at the bend. These methods have been successful in several types of tubes, and in most cases flattening and wrinkles are discreet and no kinks are visible. However, many users
Affects design from a mechanical and aesthetic sense 4
I do not like the large curved appearance of double diameter curved parts. Also, changes in tube quality, bending techniques, and die fabrication all cause significant bending defects. A very recent change in fixed-column bending machines is that the reaction site is brought very close to the bending position, while at the same time preventing the bending portion from popping out during bending. This is done by equipping each of the two pivoting arms with rollers. When the mold is driven between the arms, the arms move apart. However, this method still has the problem that extra light wall components still have wrinkles and noticeable outer flattening. A more effective, even more complex and expensive bending machine is called a towed bending machine. The towed bending machine starts bending at a predetermined position, and gradually bends this part around the mold in only one direction. Usually it is done with a fixed inner mold and also with a fixed reaction position. Bending is accomplished by sliding or rolling the outer mold along an arc concentric with the shape of the inner mold. At any time, the reaction position is relatively close to the current bending position, even when high mold contact pressure is maintained. Therefore, wrinkles are minimized. However, in some exceptionally light wall components, wrinkles occur with large flattening outside the bend. Traction benders are usually unidirectional from a starting position by bending a tube between a fixed reaction position, a fixed inner mold and a movable outer part pivotally mounted in the center of the fixed mold. Bend gradually. Some variations of this have a fixed outer portion, an inner mold, and a push reaction portion that rotates together while pulling the tube around the bend. In the fixed inner mold type, the outer portion is usually a roller that moves over a fixed radius of the fixed inner mold with curved grooves that shape and support the tube during tube bending. Occasionally, the outer portion is a straight outer die and a flat roller so that the bending force is distributed over the entire tube in order to prevent deformation of the tube surface at the contact concentrated position only from the roller. Since the tube is placed on the bender prior to the bending operation, the tube can slide in 3 minutes, but it is improbable that if one tube is made of continuous bends close to each other, It's inconvenient. For ease of use, the outer portion is moved well away from the mold to lower the tube into the plane of the bender and into the mold groove. The outer part must therefore be moved back into the mold for the bending operation. After the bending operation, the outer part is moved again to release the tube. This behavior is usually
This is done by installing the outer part with a screw thread and a handle on a pedestal aligned along the radial arm. This method presents two problems; driving is inconveniently slow, and all bends in a continuous bend are required to be equal, but accurately place the outer parts to equal radial positions. It means that you cannot do it. In some industrial bending devices, the platform is moved radially of the mold by a hydraulic cylinder or other linear actuator. Adapting such a bending machine only for industrial mass production of products using curved tubes requires a great deal of preparation and
It becomes physically large.

SUMMARY OF THE INVENTION It is an object of the present invention to substantially improve upon some of the inconveniences associated with conventional tube bending machines.

In the present invention, a mold having a main body and a mold surface installed on the main body and extending at a certain radius and at an angle to the center of the bending axis (1 in the longitudinal direction of the mold surface). The pipe is bent), and a bending arm axially attached to the main body for axial rotation movement about the axis, and a bending part installed on the arm (the part is an axis center parallel to the bending axis). And includes two deforming rollers rotatably mounted at a distance radially outward from the surface, the rollers performing bending work when the one tube moves at an angle about the axis. It is adapted to
The two rollers located in the radial direction of the bending axis are
When used, the rollers are located approximately in the curved portion of the pipe and are farther from the bending axis in the radial direction than the rollers in the forward direction. There is provided a pipe bending machine comprising another roller which is present at a distance and power means for causing an angular movement of the arm around the shaft in a position to move the roller which deforms the tube.

EXAMPLE A traditional fixed column bending machine 1 as shown in FIG.
0 uses a rigid bending mold 11 that controls both the cross-sectional contour and the bend radius. The fixed posts 12 are placed apart while the mold 11 is pressed against the inter-post components to create the bend. FIG. 11 shows a variation of the traditional fixed column bending machine.
The reaction position 13 is brought very close to the bending portion position, and the reaction position 13 is moved outward (direction of arrow 14) as the bending work progresses. This is done by placing the roller 15 on each of the two pivot arms 16. 12
Shows a conventional towed bending machine 20. The fixed inner mold 21 is
Cooperate with outer mold 22 that slides or rolls.

In the prior art, each of these prior art devices was briefly described and the limitations were partially described. Wrinkles appear to occur in these and other devices. This is because the actual bending position lags the maximum contact pressure position.
Therefore, the tube or forming part is lifted from the inner mold by levering from the reaction position and the maximum contact pressure position. This contact pressure is concentrated on the bending portion during the bundle until the new bending position is fixed at the contact position. This circulation continues, causing wrinkles. This is shown in FIG. Here, A is the reaction position, B is the maximum contact pressure position, and C is the bending position. By providing a second position of contact pressure in the curved position, it is possible to avoid the circulation of wrinkle formation. An apparatus for accomplishing this is shown in FIG. As shown in FIG. 1, the inner mold 50 includes a peripheral groove 51 that follows the shape of a bendable piece 52. Generally, the component 52 is a cylindrical tube and the cross section of the groove 51 is about half the circumference of the tube. However, the invention is not limited to bending cylindrical tubes. The inner die 50 is the outer die 53
Works in cooperation with. The outer mold 53 comprises at least two means for exerting pressure on the component 52. The means for exerting pressure for the purposes of this embodiment are rollers 54. However, this means need not be a roller, a slip shoe or various other pressure exerting devices could be used in place of roller 54. The roller 54 is provided on the shaft turntable 55. The platform 55 rotates about an axis 56. Normally, roller 5
4 has a concave peripheral groove which matches the cross section of the part to be bent. Since the base 55 rotates about its axis, the reaction acting on the first roller 57 is transmitted to the second roller 58 located at or near the curved position. This reaction acts so that the tube or material in the curved position is completely contained within the inner mold 50. Therefore, the bending position does not lag the maximum pressure position. Therefore, the bending operation can be continued without wrinkle circulation.
One advantage of this system is that the small groove of the inner mold 50 does not have to hold down the curved material. The shape of the mold section is not critical, as no pressing of the mold is required.
By limiting the coverage of the inner mold to half the tube diameter and allowing the outer mold 54 to have the coverage of half the tube diameter as well, the tube cross section is completely covered in the curved position and the outer flattening is minimized. Become. The radius of the mold can be reduced while maintaining good bending quality in a wide range of parts. The primary outer die 57 provides bending force in a short time and the dependent outer die 58 provides force to the material to include and control the shape of the material into the inner die 50. The outer dependent mold 58 is preferably in or near the curved position, but need not be exactly in the curved position. In the preferred embodiment, a few millimeters of spacing remains between the outer diameter of the dependent mold and the outer diameter of the inner mold. It is thus ensured that the pressure exerted by the depending edge mold also acts on the part or tube which is subject to bending and is not transmitted directly to the inner mold. Since the distance between the two outer molds can be changed sufficiently, the contact between the mold and the bent material can be approached and isolated. Furthermore, the two outer molds are often installed on a general rotary shaft and can be moved and removed by a single method. Hydraulic, pneumatic, electrical, magnetic, or mechanical devices are used to move and remove each outer mold to a position independent of the other outer molds. Axle rotation point 5 of platform 55
6 to change the profile, and therefore the outer mold 58
In order to change the contact pressure due to, the outer mold is moved relative to the center of rotation. The advantages of the present invention are obtained regardless of whether the rollers and pedestal 55 rotate about the center of the inner mold, or whether the mold and the curved parts rotate about a set of stationary outer molds. Similarly, the rollers or other means for exerting pressure will likely be mounted on a rotating arm or otherwise moved into position. The two sets of outer dies are installed so that the bending machine simultaneously advances in opposite directions around the inner die to increase the bending speed of the parts.
FIG. 2 shows an example of the tube bending device 60 utilizing the in-line roller 61, which is disclosed in FIG. Roller 62
Is installed on a general base 63 that rotates around an axis rotation point 64. The base 63 rotates about an arm 65 that rotates about a center 66 of the inner die 67. The central post 68 provided with the inner mold also supports an arm 69 that supplies a fixed reaction position 70 for the material 71 to be bent. The hydraulic cylinder 72 cooperates with the link mechanism 73 to form the arm 65.
However, the inner mold can be rotated 180 °. This particular combination for rotating arm 65 is more fully described in Australian Patent Application No. 58906/90. A tube bender 100 is schematically depicted in FIGS. 3-9 of the accompanying drawings. The bending machine 100 includes a body 11 having legs 112 for supporting the body 111 on the ground.
Has 1. The main body 111 is basically a main pin 11
4 is a hollow housing that pivotally supports an arm 113 for axial rotational movement about a general vertical axis defined by 4. Installed at the radial tip of the arm 113 is a bender assembly 115 including a platform 116.
The platform 116 is slidably mounted on the arm 113 for longitudinal movement relative to the arm 113. This movement is provided by the outer end pass-through shaft 117, together with the adjusting wheel or lever 118. The shaft 117 is
The arm 113 meshes with the passage 119 through which the arm 113 can pass. The bending machine assembly 115 further includes a second pin 1
It includes a roller support 120 that is pivotally mounted at 40. Support 1
20 cooperates with a set of generally vertically spaced horizontal flanges to support two or more rollers. In this particular example, two rollers 122 and 123 are provided. The flange 121 is a support 120.
They are joined using a handle 124 that is pivotally supported by exiting through an interior passage. Each roller has 12 pins
It is supported by using 5. The roller 122 is located in the curved position, and the roller 123 is located in front of it. The roller 123 is positioned at an angle in front of the roller 122 with respect to the bending axis, and is positioned further outward than the roller 122 in the radial direction. Inside the main body 111 is a cylinder 127 that is pivoted at one end by a pin 145.
Is a water hammer pump 126. Water hammer pump 126
Has a piston rod 129 ending at the core 128. The core 128 is pivotally attached to the link 129 by a pin 130. The other end of the link 129 is pivotally attached to the arm 113 by a pin 131. Arm 113 also has pin 1
It has a socket 146 that receives the pin 130 during various states of movement of the arm 113 about 14. Also mounted on the body 111 is a mold 132 having a mold surface 133 extending at an angle, generally a constant radius, about the pin 114. In this particular example, the mold surface 132 has a vertical cross-section. The single tube 134 that is deformed by the bender 100 is generally bent to follow the surface 132, so the pin 114 also defines the bending axis about which the tube 134 is bent. The movement of the water hammer pump 126 is controlled by a spool valve 135 operated by a lever 136 extending up through the body 111. The spool valve 135 transfers the hydraulic fluid under pressure to the cylinder 127. Spool valve 135 is lever 136
When moving in the first direction, the hydraulic fluid under pressure is transferred to the cylinder 127 so that the piston rod 129 extends in the cylinder 127 in a telescopic manner.
This telescopic movement begins when the water hammer pump 126 is configured as shown in FIG. Piston rod 1
When 27 is extended, the arm 113 causes axial rotation due to the interlocking state of the pin 130 with the socket 146. This continues until the arm 113 reaches the position shown in FIG. In this position, the arm 113 pivots to disengage the pin 130 from the socket 146. However, the arm 113 continues to axially rotate due to the force applied by the link 129 to the arm 113. The spool valve 135 has (pin 12
5) a cam follower 136 for rotating a cam 137 fixed to the arm 113 with the arm 113.
The cam 137 is adjusted to return the spool valve 135 to the starting position and / or to cause the spool valve 135 to return the arm 113 to the starting position. Therefore cam 1
37 can be used to control the bend angle of tube 134. The mold 132 is provided on the pin 114, but is removable. The radii can be varied as different sized molds are available. The mold 132 has a protrusion 140
The mold 132 remains stationary during operation because it has a rear recess 139 on the body 111 that mates with. In addition, a tube support 141 is provided on the body 111 that holds a portion of the tube 134 stationary with respect to the body 111 during bending. In operation of the bending machine 100 described above, the bending machine 100 is described as bending in one predetermined direction. However, bending can also be done in the opposite direction. This is accomplished by removing the mold 132. Then lever 136
Is removed together with the cam 137 by loosening the bolt 138. The handle 118 is therefore rotated to remove the bending work assembly 115. Next, the main pin 114 is removed, and the arm 113 is pulled out from the inside of the main body 111. This is cylinder 12
This is accomplished by the telescopic movement of the piston rod 127 on the surface with respect to 7. After that, the arm 113, the link 129, and the piston rod 127 rotate in the range of 180 ° about the axis of the piston rod 127.
Then, the above steps are repeated. Therefore, the water hammer pump 126 and the link 127 are located on the opposite side of the lever 136. Bending machine 100 is therefore provided with arm 113 pin 1 as opposed to counterclockwise as shown in FIGS.
Drive clockwise around 14. Pins 143 that can be installed on either side of the recess 142 are provided to keep the support 120 in place to accommodate the opposite movement. The handle 118 is rotated so that the roller 122 moves radially relative to the pin 114 to accommodate different diameter tubes. Further, two or more rollers 122 can be used with one roller in the deformed position of tube 134. While the particular structure of the invention has been described in detail, it has been described by way of specific examples which do not limit the scope or spirit of the invention.

According to the present invention, some inconveniences associated with the conventional pipe bending machine can be sufficiently improved.

[Brief description of drawings]

FIG. 1 is a front view of an in-line roller tube bending machine according to the present invention.

FIG. 2 is a front view of a bending device incorporating an array of in-line rollers.

FIG. 3 is a schematic perspective view of a pipe bending machine.

4 is a schematic cross-sectional view of a portion of the pipe bending machine of FIG.

5 is a schematic sectional view of the pipe bending machine of FIG.

6 is a schematic plan view of the tube bending machine of FIG. 3 in a continuous mode of operation.

7 is a schematic plan view of the tube bending machine of FIG. 3 in continuous mode of operation.

FIG. 8 is a schematic plan view of the pipe bending machine of FIG. 3 in continuous mode of operation.

9 is a schematic plan view of the tube bending machine of FIG. 3 in continuous mode of operation.

FIG. 10 is a front view of a conventional fixed column bending machine.

FIG. 11 is a front view of a bending machine having a conventional shaft rotation arm.

FIG. 12 is a front view of a conventional towed bending machine.

FIG. 13 is a front view illustrating the cause of defects in a traditional pipe bending machine.

Claims (12)

[Claims] 1. A main body; and a mold having a mold surface which is installed on the main body and extends at a certain radius around the bending axis at an angle (a tube is bent according to the longitudinal direction of the mold surface).
A bending arm axially attached to the body for axial rotation movement about the axis; bending parts installed on the arms (the parts are rotatably installed about an axis parallel to the bending axis, and the surface is From which the bending operation is carried out when the one tube moves at an angle about the axis). Since the two rollers located in the radial direction of the bending axis have sufficiently the same expanse, when used, the one roller located approximately in the curved portion of the pipe and the one located from the bending axis Another roller that is radially further than the roller and is at an angle to the front; power means for causing angular movement of the arm about the axis in a position to move the roller that deforms the tube. Consists of , Pipe bending machine. 2. A curved portion of the one tube further comprising a reaction portion mounted on the body for engaging the one tube and contacting the mold surface during a bending operation. The pipe bending machine according to claim 1. 3. A tube bending machine according to claim 1 or 2 having said bending arm comprising means for selecting the radial position of a bending assembly with respect to said surface. 4. The pipe bending machine according to claim 1, wherein the two deforming rollers are rotatably installed on a flange pivotally supported by the bending arm. 5. A body according to any one of the preceding claims, having said power means pivotally mounted on one end thereof, the other end comprising a water hammer pump pivotally connected to said bending arm. Tube bending machine. 6. The water hammer pump has the other end axially coupled to a link through a pin, the link in turn axially coupled to a bending arm, and during a portion of the axial rotation of the bending arm. The tube bender of claim 5 wherein the pin is adapted to contact the socket of the bending arm. 7. The pipe bending machine according to claim 5 or 6, further comprising a coupling portion installed in the main body for supplying a means for limiting an axially rotatable angle of the water hammer pump. 8. The arm, link, and water hammer pump for rotating the pipe bending machine in opposite directions are rotatable in a range of 180 ° about the water hammer pump axis. The pipe bending machine of paragraph 7. 9. Further comprising a spool valve having a cam follower which engages a cam fixed to the bending arm, the cam being adjusted to cooperate with said spool valve and thus adjusting the bending range angle of said one tube. A pipe bending machine according to any one of the preceding claims, which has been determined. 10. A tube bending machine according to any one of the preceding claims, wherein the molds are removable so that molds of different radii can be substituted. 11. A tube bending machine according to any one of the preceding claims, wherein the mold comprises a recess cooperating with a projection on the body, the projection and the recess cooperating to keep the mold stationary on the body during operation. . 12. A tube bending machine as described sufficiently above in relation to FIGS. 1-9 of the accompanying drawings.