JPS5925569Y2 - pipe bending equipment - Google Patents

Description

[Detailed description of the invention] The present invention relates to a pipe bending device for bending bent pipes such as elbow pipes with a relatively small radius of curvature.In particular, the pipe can be bent so that the straight part does not become long, and material loss can be reduced. The purpose is to provide a pipe bending device that can be reduced as much as possible.

BACKGROUND ART Conventionally, when bending connecting elbow pipes that are often used in refrigerant piping of air conditioners, a bending device having the structure shown in FIG. 4 has been exclusively used.

Pipe bending by this device is carried out as follows: the member 18 is pushed by the clamping cylinder 19, the member 20 is rotated around the fulcrum pin 17, and a bending die fitted to the member 20 is rotated. 1' to the member 5' to sandwich the copper pipe 12 to be bent,
Move the base 13 in the direction of the arrow to position the bending die 1' and the receiver 2', then operate the cylinder 21 to insert the mandrel 6' into the copper tube 12, and bend the bending die 1'.
and by rotating the member 5' around the center of the bending die 1'.

In the above device, the mold 2' and the mandrel 6' are fixed during processing, while the bending mold 1' and each member 18.
5' and the clamping cylinder 19 are rotated, and when the length of the part clamped by the bending die 1' and the member 5' in the tube axis direction is short, the clamping cylinder 19 can be clamped evenly. Installation is not affected, and the catch is mold 1' and mandrel 6'.
When the member 5' is pressed, force is applied, which becomes resistance during the bending process, and the copper tube 1 at the end 5'a of the member 5'
As a result of slippage between the copper tube 2 and the member 5', the bent portion of the copper tube 12 becomes flat, resulting in poor finishing accuracy.

In addition to adjusting the position of the stopper 14 as the dimensions of the connecting elbow pipe change, the receiver also lengthens the mandrel 6' inserted into the copper pipe 12 as the relative position between the mold 2' and the cylinder 21 changes. It is necessary to replace it with one of a different size, which is cumbersome to handle.

Furthermore, since the mandrel 6' and the copper tube 12 have a structure in which the insertion state is maintained in a fixed state throughout the bending process, a considerable length of straight pipe section is required. In many cases, a specified piping connection cannot be made without cutting off the straight pipe portion of the pipe, which has the disadvantage of leading to material loss.

In view of the fact that the above-mentioned conventional devices have various deficiencies, the present invention has been developed.In particular, the bending die and the receiver are fixed and do not move during the bending process. On the other hand, the pressing mold and mandrel have a movable structure that can rotate together in accordance with the bending process, resulting in a device that is completely different in form from conventional devices. It is characterized by being able to eliminate various defects.

The specific contents of the device of the present invention will be explained in detail below based on one example of the device shown in the accompanying drawings.

FIG. 1 is a front view showing the main structure of an example of the device according to the present invention, and this device includes a bending mold 1, a receiving mold 2, a stop member 3, a pressing member 4, and a pressing mold 5. The main component is a mandrel 6.

The bending die 1 has a straight circumferential surface part and a semicircular circumferential surface part on both sides of the bending starting point p, and a semicircular groove 7 having a shape that can follow the circumferential surface of the straight pipe 12 to be bent is formed as shown in FIG. It is recessed in the same peripheral surface.

This bending die 1 is fixed in position by support pins 15.

The receiving mold 2 is connected to the straight peripheral surface of the bending mold 1 to form a straight pipe 12.
For example, it is a mold for holding one end of a steel pipe, and a semicircular groove 8 symmetrical to the semicircular groove 7 is recessed in the surface opposite to the straight circumferential surface.

The above mold 2 is moved in a direction parallel to the straight peripheral surface of the bending mold 1 by the base 13 which is fixed to the base 13 and slides in the direction of the arrow, and is stopped at a predetermined position by the stopper 14. The semicircular groove 7 of the bending mold 1 and the semicircular groove 8 are opposed to each other, so that one end of the straight pipe 12 can be clamped with an appropriate force.

On the other hand, the abutment member 3 has the bending die 1 and the receiver fixed while maintaining their relative positions with the die 2, and the tip of the stopper member 3 is inserted between the opposing double circular grooves 7 and 8 and is held in place. It is brought into contact with the end of the pipe 12, and is used to position the end of the straight pipe 12.

Next, the pressing member 4 is formed from a cylindrical body 9 and an extrusion cylinder 10, and connects the rod of the extrusion cylinder 10 fixed to the frame 16 and the base of the cylindrical body 9 in parallel axes, and The cylindrical body 9 coaxially approaches and separates from the straight pipe 12 held between them as the rod moves forward and backward.

The cylinder body 9 is a cylinder having approximately the same diameter as the straight pipe 12, and by contacting the other end of the straight pipe 12, the cylinder body 9 cooperates with the stop member 3 to close the straight pipe 12. In this case, the straight pipe 12 and the cylindrical body 9 form a coaxial hollow.

The support mold 5 is fixed to the frame 16, and has a shape along the circumferential surface of the straight pipe 12 on the surface that contacts the clamped straight pipe 12, and a receiver in the semicircular groove 8 of the mold 2. On the other hand, semicircular grooves 11 that can be lined up are recessed.

The mandrel 6 is of an appropriate length and is loosely inserted into the cylindrical body 9 and screwed onto the frame 16 so that the length can be adjusted slightly in and out. with a loose fit hole, and is inserted through the straight pipe 12 and the cylinder body 9,
It extends close to the stop member 3.

The structure of each main member is as explained above.
The receiver is a member that is fixed after adjusting the mutual positional relationship between the die 2 and the stopper member 3, while the pressing member 4, the abutment die 5, and the mandrel 9 are movable members that integrally revolve around the bending die 1. By rotating the frame 16, the above-mentioned revolution is effected.

This revolution movement is specified as a movement that causes the frame 16 to move in a circle around the support pin 15, and
In this way, the pressing mold 5, the cylinder 9 of the pressing member 4, and the mandrel 6 maintain their relative positions, and also maintain their positions in the approximately tangential direction with respect to the semicircular groove 7 provided in the semicircular arc-shaped peripheral surface of the bending mold 1. Then, they come to revolve around the bending die 1 as a unit.

Next, the operation of bending a pipe using the device of the present invention will be explained.

Between the semicircular groove 7 of the bending die 1 and the semicircular groove 8 of the die 2, the receiver positioned by the stopper 14 holds one end of a straight pipe 12 cut to a predetermined length and loosely fitted into the mandrel 6. It is inserted until it hits the abutment member 3 and is held between the molds 1 and 2, and is supported from below by the abutment mold 5.

Next, the extrusion cylinder 10 is operated to extrude the cylindrical body 9 until it touches the other end of the straight pipe 12.

This initial state is as shown by the solid line in FIG. 1, and the straight pipe 12 is reliably positioned by both the members 3 and 4.

Note that the length of the straight pipe 12 at the portion where it is sandwiched between the bending die 1 and the receiver die 2 may be sufficiently short so as not to cause slippage.

From this state, the frame 16 is rotated to bend the pipe, but as the support mold 5, cylinder 9, and mandrel 6 rotate around the bending mold 1, the straight pipe 12 fits into the semicircular groove 7 of the bending mold 1. When the straight pipe 12 reaches the position shown by the two-dot chain line in FIG. 1, it is bent approximately 90 degrees.

Looking at the actions of the stopper die 5, cylinder body 9, and mandrel 6 during the bending process at that time, in the initial state, the stopper die 5 faces the bending starting point p, and the curved corner portion 5a slides on the half circumferential surface of the straight pipe 12. It acts to press the straight pipe 12 against the bending die 1 while handling it while touching it.

On the other hand, as the mandrel 6 rotates, it moves within the straight pipe 12 toward the drawing side, and guides the straight pipe portion along the bending mold 1 while escaping from the bending portion.

Furthermore, the cylinder 9 always holds the tube 12 against the bending mold 1 so that it does not slip due to the pressing force of the extrusion cylinder 10.

In this way, by cooperating with each other,
A bent tube 12' having a shape corresponding to one bending die is obtained without flattening (see FIG. 3).

When the bending process is completed, the bent tube 12' can be easily taken out by moving the mold 2 to the right in FIG. 1 and retracting the extrusion cylinder 10.

Next, the effects of the present invention are as follows.

(a) Since the pipe to be bent is held between the stop member 3 and the pressing member 4 during the bending process, the bending die 1 and the pipe 12 are positioned relative to the stop member 3.
There is no slippage between the two, and flattening of the bent portion is reliably prevented.

(b) Since the mandrel 6 escapes from the bent portion and guides the straight portion of the tube 12 along the bending die 1, a highly accurate bent tube that matches the bending die 1 can be obtained.

(c) Since the position of the mandrel 6 with respect to the bending mold 1 exists in a fixed relationship, even if the position of the receiving mold 2 is changed depending on the length of the tube 12, there is no need to replace the mandrel 6 or adjust the dimensions. Quality can be improved.

B) The bending die 1 and the receiver are fixed to the die 2, and the movement of the tube 12 is reliably prevented by the stop member 3 and the pressing member 4, so even if the straight part is shortened or shortened, it can be accurately This allows for flexible bending, eliminates the need to cut off straight parts during connection, and causes no material loss.

As described above, the present invention has various excellent effects and is an extremely useful pipe bending device.

[Brief explanation of the drawing]

Fig. 1 is a schematic front view of an example of the device of the present invention, Fig. 2 is a cross-sectional view taken along the I - I arrow line in Fig. 1, Fig. 3 is a perspective view of a bent pipe, and Fig. 4 is a conventional FIG. 2 is a schematic front view of the tube bending device. 1...Bending die, 2...Bending is die, 3...
... Stopping member, 4... Pressing member, 5...
...Mold, 6...Mandrel, 7...
...Semicircular groove, 10...Extrusion cylinder, 11
...Semi-circular groove, 12...Straight pipe.

Claims (1)

[Scope of utility model registration request] A fixed bending mold 1 having a semicircular groove 7 continuous and recessed in a straight peripheral surface portion and a semicircular arc peripheral surface portion existing on both sides of the bending starting point p, and a recessed portion in the straight peripheral surface portion of the bending mold 1. The straight pipe 12 has a semicircular groove 8 symmetrical to the semicircular groove 7 formed in the straight pipe 12 and is to be bent by the semicircular grooves facing each other.
A fixed receiver capable of clamping one end portion is a mold 2; the receiver is abutting member 3 which is brought into contact with the pipe end at the one end portion of the straight pipe 12 held between the mold 2 and the bending mold 1; Straight pipe 1
A pressing member 4 that can coaxially press a cylinder 9 against the pipe end at the other end of the cylinder 9 and clamping and fixing the straight pipe 12 between the cylinder 9 and the stopper member 3; 12, the receiver is passed through a stopper mold 5 having a semicircular groove 11 that can be aligned with the semicircular groove 8 of the mold 2, the cylinder body 9 and the straight pipe 12 clamped and fixed. It consists of a mandrel 6 into which a hole is loosely inserted, and a mold 5, a mandrel 6 and a cylinder body 9.
is able to integrally revolve around the bending die 1 while maintaining its relative position and approximately tangential position with respect to the semicircular groove 7 provided on the semicircular arc-shaped peripheral surface of the bending die 1. A pipe bending device characterized by: