TW202348328A - Pipe bending machine capable of reducing the load applied to a covering material when bending covered piping - Google Patents

Abstract

An object of the present invention is to provide a pipe bending machine for reducing the load applied to a covering material when bending covered piping. To achieve the object, the pipe bending machine of the present invention is a pipe bending machine for bending covered piping and characterized by including a push rod; a wheel mold provided at a front end of the push rod and formed with a wheel mold groove portion for clamping the covered piping during bending; and a pair of left and right roller portions for supporting the covered piping during bending. The wheel mold groove portion includes: a first wheel mold groove portion formed in a tapered shape; and a second wheel mold groove portion having a connecting groove portion connected to the first wheel mold groove portion, wherein the width of the connecting groove portion is larger than the outer diameter of the pipe included in the covered piping.

Description

Pipe bending machine

The present invention relates to a pipe bending machine used for bending coated pipes.

As a machine for bending pipes of air conditioners and the like, pipe bending machines are known. Conventionally, in order to prevent the pipe from cracking when bending the pipe, a coil-shaped spring was arranged in the pipe (for example, see Patent Document 1).

Patent Document 2 discloses a method for manufacturing a two-layer pipe in which an inner pipe is installed as a sandwich inside an outer pipe. The method is characterized by inserting a core material only into the inner pipe and connecting it with the inner pipe. The aforementioned inner tube and the aforementioned outer tube are bent together.

Patent Document 3 discloses a pipe bending device, which is provided with a roller and a clamp that clamps the side surfaces of a plastically deformable metal pipe from both sides; and a stopper that prevents the movement of the pipe in the radial direction; and clamps the pipe. A pipe bending device for bending a pipe by using the roller as a fulcrum and rotating the roller and the clamp together while being held between the roller and the clamp, characterized in that the stopper is provided with A plurality of rollers rotatably support the tube along the longitudinal direction of the tube, and use the plurality of rollers to prevent movement in the radial direction of the tube.

[Prior technical literature] (patent document) Patent Document 1: Japanese Utility Model Registration No. 3172929 Patent Document 2: Japanese Patent Application Publication No. 2019-75622 Patent Document 3: Japanese Patent Application Publication No. 2010-5653

[Problem to be solved by the invention] However, the above-mentioned Patent Documents 1 to 3 do not consider any technical problems when bending a covered pipe, which is a pipe covered with a coating material. That is, when bending a covered pipe, if the load applied to the covering material is too large, the covering material may be broken. Therefore, a pipe bending machine that can solve this technical problem is required. Furthermore, in the method of Patent Document 1, when the spring is pulled out from the pipe after bending, there are problems such as the spring being hooked on the pipe and being unable to be pulled out, or the spring being broken.

[Technical means to solve problems] In order to solve the above problems, the pipe bending machine of the present invention is (1) a pipe bending machine for bending coated pipes, and is characterized in that it has: a push rod; a wheel mold provided at the front end of the push rod, and A wheel mold groove portion is formed which clamps the covered pipe when bending the pipe; and a pair of left and right roller portions which support the covered pipe when bending the pipe are formed.

(2) The pipe bending machine according to the above (1), wherein the wheel mold groove portion has: a first wheel mold groove portion formed in a tapered shape; and a second wheel mold groove portion provided with a connecting groove portion to connect to the pipe bending machine. The width of the first wheel mold groove portion and the connecting groove portion are larger than the outer diameter of the pipe included in the covered pipe.

(3) The pipe bending machine according to the above (2), wherein when the width of the connecting groove is defined as W and the outer diameter of the pipe is defined as R, the difference between the width W and the outer diameter R is 5 mm. Above and within 20mm.

(4) The pipe bending machine according to the above (2) or (3), wherein the second wheel mold groove portion has an arcuate groove portion connected to the connecting groove portion and having a curvature radius substantially the same as that of the pipe.

(5) The pipe bending machine according to any one of the above (1) to (4), wherein the wheel mold is formed into a substantially semicircular shape in plan view, and the wheel mold groove portion is formed along the shape of the wheel mold. The outer edge is formed.

(6) The pipe bending machine according to any one of the above (1) to (5), wherein the roller part is composed of a plurality of small rollers stacked up and down; and, the plurality of small rollers Each child can rotate independently using a common shaft extending in the up-and-down direction as a rotation axis.

(7) The pipe bending machine according to the above (6), wherein a gap is formed between the rotating shaft and each of the small rollers.

(8) The pipe bending machine according to any one of the above (1) to (7), including a plate portion extending in a direction substantially perpendicular to the longitudinal direction of the extrusion rod; and the roller portion fixed to the aforementioned plate.

(9) The pipe bending machine according to any one of (1) to (8) above, wherein the extrusion mechanism of the extrusion rod is a ratchet type.

(10) The pipe bending machine according to the above (9), having a lever connected to the extrusion mechanism; and the extrusion rod is extended by rotating the lever from the open position to the closed position. .

(11) The pipe bending machine according to the above (10), further comprising an energizing member that energizes the joystick from the closed position toward the open position.

(12) The pipe bending machine according to any one of the above (1) to (11), wherein the covered pipe is composed of a pipe and a heat-insulating coating material covering the outer periphery of the pipe.

(13) The pipe bending machine according to any one of the above (1) to (12), wherein the wheel mold is detachably attached to the front end of the joystick.

[Effects of the invention] According to the present invention, it is possible to provide a pipe bending machine that imposes a small load on the covering material.

The pipe bending machine 100 of this embodiment can be used for bending coated pipes. Covered piping is a piping that transports refrigerant that circulates between an outdoor unit and an indoor unit of an air conditioner, and is configured to cover the periphery of a copper pipe (piping) with a thermal insulation material (heat insulation material). In insulation materials, polyethylene and the like are generally used. Covering copper pipes with insulation material can prevent condensation, etc.

Figure 1 is a top perspective view of the pipe bending machine (with the wheel mold installed). Figure 2 is a top perspective view of the pipe bending machine (without the wheel mold installed). Figure 3 is a bottom perspective view of the pipe bending machine when the joystick is closed. Figure 4 is a bottom perspective view of the pipe bending machine when the joystick is opened. Referring to these figures, the pipe bending machine 100 includes an extrusion rod 15, a joystick 20, a buckle 25, a unilateral spring (equivalent to an energizing member) 30, a fixing bolt 35, a plate part 45, a roller part 50, and Wheel mold 60. In addition, FIGS. 3 and 4 illustrate the pipe bending machine 100 in a state in which the wheel mold 60 is removed.

The machine body 10 is formed in an elongated shape, and a body flat portion 11 is formed on one end side. The joystick 20 is installed to be rotatable within a prescribed range relative to the machine body 10 . A donut-shaped spring hook 21 is formed at one end in the longitudinal direction of the joystick 20 . A first spring hook 31 is formed on one end of the unilateral spring 30 , and a second spring hook 32 is formed on the other end. The first spring hook portion 31 hooks the spring hook portion 21 of the operating lever 20; the second spring hook portion 32 is fixed by clamping the bolt 10A fastened to the machine body 10 and the bottom surface of the machine body 10.

Here, in the open state of the joystick 20 shown in Figure 4, if the joystick 20 is rotated toward the machine body 10 (in other words, if it is rotated toward the closed position), the single-sided spring 30 will stretch and store. The spring force used to return the operating lever 20 to the open position.

The buckle 25 is formed in a U-shape, and has protrusions protruding toward the side surfaces of the machine body 10 at both ends. These protrusions snap fit into openings formed on the side surfaces of the machine body 10 . In addition, buckle refers to a fixation method that uses the elasticity of the material to embed. The buckle 25 can rotate relative to the machine body 10 using the convex portion as a rotation axis.

Figure 3 shows a state in which the lever 20 is held in the closed position by the buckle 25 . In the same figure, if the buckle 25 is rotated to a position where it does not interfere with the joystick 20, the spring force stored in the unilateral spring 30 will cause the joystick 20 to move from the closed position (see Figure 3) to the open position. (Refer to Figure 4) Reset.

The extrusion rod 15 is accommodated in a guide groove 10B extending along the longitudinal direction of the machine body 10, and a rack 15A is formed on the bottom surface of the extrusion rod 15. Whenever the operating lever 20 is rotated from the open position to the closed position, the push-out rod 15 will be extended according to the spacing of the rack 15A. That is, in this embodiment, a ratchet mechanism is used as the extension mechanism of the extrusion rod 15, and the extrusion rod 15 can be intermittently extended along the guide groove 10B by operating the operating lever 20. In addition, in the following description, the extending direction of the extrusion rod 15 can also be said to be the extrusion direction.

Figure 5 is a diagram illustrating the operation of the ratchet mechanism. For convenience of description, in the rack 15A of the extrusion rod 15, the teeth adjacent to one of the extrusion directions are defined as front teeth 15A1, and the other teeth are defined as rear teeth 15A2. A box portion 20A protruding toward the extrusion rod 15 is formed at the front end of the operating lever 20 . In this box part 20A, the spring 20B is accommodated in a telescopic state. A claw portion 20C is attached to the upper end of the spring 20B, and the claw portion 20C protrudes from the top surface of the box portion 20A.

In the state shown in FIG. 5 , when the lever 20 is rotated toward the closed position, the claw portion 20C comes into contact with the front teeth 15A1 and the push-out rod 15 is pushed out in the push-out direction. As mentioned above, the control lever 20 rotated to the closed position automatically returns from the closed position toward the open position by the spring force of the unilateral spring 30 . When the lever 20 is automatically returned to the open position, the claw portion 20C collides with the rear teeth 15A2 from the front side in the pressing direction. At this time, by the contraction of the spring 20B, the claw portion 20C passes over the rear teeth 15A2 and returns to the original position (the position shown in FIG. 5). By operating the joystick 20 and repeating these operations, the extrusion rod 15 can be intermittently extended in the extrusion direction.

In this embodiment, a ratchet mechanism is used as the extension mechanism of the extrusion rod. However, the present invention is not limited to this, and it may also be a hydraulic type or an electric type.

Figure 6 is a front view of the wheel mold. The wheel mold 60 is formed with a wheel mold groove portion 61 that clamps the covered pipe when the covered pipe is bent. The wheel mold groove part 61 is composed of a first wheel mold groove part 61A and a second wheel mold groove part 61B connected to the first wheel mold groove part 61A. The first wheel mold groove portion 61A is composed of a pair of opposing tapered surfaces separated by a gap up and down, and these tapered surfaces extend in a circular shape when viewed from above. The upper end of the cone surface on the upper side protrudes toward the outside of the wheel mold 60 than the lower end; the lower end of the cone surface on the lower side protrudes toward the outside of the wheel mold 60 than the upper end.

In this embodiment, the first wheel mold groove portion 61A is formed so that the tapered surface becomes a semicircle when viewed from above. However, the present invention is not limited to this. For example, the arc shape may be less than a semicircle (that is, the central angle is less than 180∘).

Here, the maximum distance between a pair of opposing tapered surfaces (in other words, the distance between the upper end of the upper side tapered surface and the lower end of the lower side tapered surface) is preferably set to approximately the outer diameter of the covered pipe. same. The outer diameter of the covered pipe refers to the diameter of the outer peripheral surface of the covering material. By setting the maximum distance to be substantially the same as the outer diameter of the covered pipe, pipe bending can be started with the outer surface of the covering material in contact with the tapered surface of the first wheel mold groove portion 61A, so that the application can be The load on the coating material becomes smaller.

The second wheel mold groove portion 61B is composed of a pair of flat portions 61B1 (corresponding to the connecting groove portion) extending in a direction parallel to the extrusion direction, and an arc portion 61B2 (which connects the terminal ends of the pair of flat portions 61B1). Equivalent to an arc groove). The pair of flat portions 61B1 are spaced up and down and face each other, and the distance between them is fixed. That is, the groove width W formed by the pair of flat portions 61B1 is constant. The radius of curvature of the arc portion 61B2 is substantially consistent with the outer diameter of the pipe. The outer diameter of the pipe refers to the diameter of the outer circumferential surface of the pipe.

Here, when the outer diameter of the pipe is defined as R, the groove width W is larger than the outer diameter R. It is preferable that the difference between the width W and the outer diameter R is 5 mm or more and 20 mm or less. By setting the difference between the width W and the outer diameter R to 5 mm or more, when the covered pipe is sandwiched into the wheel mold groove 61 and bent, it is possible to ensure that the coating material is pressed into the second wheel mold groove 61B. space, so it can prevent defects such as cracking of the covering material. In addition, by limiting the difference between the width W and the outer diameter R to 20 mm or less, the covered pipe in the bent pipe will swing within the range of the groove width W and prevent the pipe from being bent into the desired shape. Different shapes etc.

An opening for attaching and detaching the wheel mold (not shown) is formed on the rear end surface of the wheel mold 60, and the extrusion rod 15 is pressed into the opening for attaching and detaching the wheel mold, thereby enabling the wheel mold 60 to be extruded. Rods 15 are connected to each other. However, the present invention is not limited to this, and the wheel mold 60 may also be fixed to the extrusion rod 15 in a non-detachable manner.

A board mounting groove 10C extending in the width direction of the machine body 10 is formed at the front end of the machine body 10 . Screw holes (not shown) are formed on the bottom surface of the board mounting groove 10C. The plate portion 45 is accommodated in the plate mounting groove portion 10C of the machine body 10 . The thickness of the plate portion 45 is set to be substantially the same as the depth of the plate mounting groove portion 10C. Therefore, when the plate portion 45 is accommodated in the plate mounting groove portion 10C, the plate portion 45 and the top surface of the machine body 10 are substantially aligned with each other on the same plane.

The plate portion 45 is formed with screw holes 45A. The screw holes of the plate mounting groove 10C are aligned with the screw holes 45A of the plate portion 45, and the fixing bolts 35 are tightened from the bottom side of the machine body 10. This enables the plate portion 45 to be fixed to the machine body 10 . By releasing the fastening of the fixing bolts 35 from these screw holes, the plate portion 45 can be removed from the machine body 10 .

The pair of left and right roller portions 50 are fixed to the plate portion 45 and are arranged in substantially symmetrical positions across the machine body 10 when viewed from the longitudinal direction of the machine body 10 . The roller part 50 is composed of a plurality of small rollers 51, and these small rollers 51 are stacked up and down and inserted into a shaft part (corresponding to a common shaft part) extending in the up and down direction. Some gaps are formed between the shaft part and each small roller 51 . The roller portion 50 desirably has a height exceeding the outer diameter of the covered pipe. This is because if the roller portion 50 has a height exceeding the outer diameter of the covered pipe, the covered pipe can be reliably brought into contact with the roller portion 50 when bending the pipe.

The lower end of the shaft portion of the roller portion 50 penetrates the plate portion 45 and is fixed to the bottom surface of the plate portion 45 in a snug fit. However, the portion of the shaft that penetrates the plate portion 45 may be fastened with a fastening member such as a nut to fix the shaft. A roller dropout prevention portion 52 is provided at the upper end of the shaft portion of the roller portion 50 . The diameter of the roller fall-off preventing portion 52 is set larger than the diameter of the small roller 51 . This prevents the small roller 51 from falling off from the shaft. A fastening member (for example, a bolt or a nut) fastened to the upper end of the shaft part can be used in the roller fall-off prevention part 52 . When the roller detachment prevention part 52 is a bolt, a hexagonal hole bolt having a hexagonal hole in the bolt head, a slotted bolt having a slotted groove in the bolt head, or a cross-shaped bolt having a cross groove in the bolt head can be used. A cross groove bolt, etc. is attached as this bolt. In FIGS. 1 and 2 , a hexagonal hole bolt is shown as an example of the roller detachment prevention part 52 .

The adjacent small rollers 51 have their axial end surfaces in contact with each other. Each small roller 51 can rotate independently of each other. In this embodiment, four small rollers 51 are combined to form one roller part 50, but a plurality other than four may be used. By using a plurality of small rollers 51 , the load applied to the covering material during pipe bending can be reduced, thereby preventing cracking of the covering material and the like. However, the roller part 50 may be comprised of one roller.

Next, the operation of the pipe bending machine 100 will be described. In the initial state, the joystick 20 is in the closed position (see Figure 3). The covered pipe is arranged in a direction substantially parallel to the longitudinal direction of the plate portion 45 and sandwiched between the tapered surface of the first wheel groove portion 61A and the roller portion 50 .

After the covered pipe is installed, if the buckle 25 is released, the spring force of the unilateral spring 30 causes the operating lever 20 to rotate from the closed position to the open position. In addition, before installing the covered pipe, the buckle 25 may be released and the operating lever 20 may be rotated from the closed position to the open position in advance.

Next, the lever 20 is manually rotated from the open position toward the closed position, and the wheel mold 60 mounted on the front end of the extrusion rod 15 is directed toward and pressed into the covered pipe. The covering pipe is supported by a pair of left and right roller portions 50 and resists movement in the pressing direction. Therefore, the covering material of the covering pipe is pressed against the tapered surface of the first wheel mold groove portion 61A and deformed.

If the wheel mold 60 is directed toward the covering material and further pressed into the covering pipe, the covering pipe will be gradually pressed into the second wheel mold groove portion 61B from the tapered surface of the first wheel mold groove portion 61A to cover the entire wheel mold. Cover the piping and bend it.

According to this embodiment, the coating material is pressed against the tapered surface of the first wheel mold groove portion 61A and is compressed and deformed, and then the covered pipe is pressed into the second wheel mold groove portion 61B. Therefore, it is possible to reduce the impact on the coating during pipe bending. The load exerted by the material. Here, assuming that the coated pipe is bent using a wheel mold (see FIG. 7 ) in which the first wheel mold groove portion 61A is omitted and only has the second wheel mold groove portion 61B, the second wheel mold groove portion The edge of the flat portion 61B1 of 61B contacts the covering material and may cause cracks. In this embodiment, before the covered pipe is pressed into the second wheel groove portion 61B, the covering material is pressed against the tapered surface of the first wheel groove portion 61A, thereby making it easier to enter the second wheel mold groove portion 61B. shape, so related adverse situations can be prevented.

In addition, when bending the pipe, each small roller 51 is inclined within the range of the gap formed with the shaft part, and the small roller 51 itself rotates, thereby preventing the coating material from being damaged by the roller part 50 Applying excessive load. This can prevent the coating material from cracking when bending the pipe.

In this way, according to the pipe bending machine of this embodiment, when bending the covered pipe, there is no need to insert a coil-shaped spring into the pipe, etc., so the work load during pipe bending can be reduced. In addition, there is no need to pull out the spring from the pipe after bending, so the above-mentioned problems such as spring breakage are eliminated. In addition, when bending the pipe, problems such as cracking of the coating material covering the pipe can be eliminated.

In the above embodiment, the second wheel mold groove portion 61B of the wheel mold 60 is composed of the flat portion 61B1 and the arc portion 61B2. However, the present invention is not limited to this, and the arc portion 61B2 may be omitted as shown in Figure 8. .

10:Machine body 10A: Bolt 10B: Guidance ditch 10C: Groove for plate installation 11: Flat part of body 15:Press out rod 15A:Rack 15A1: Front teeth 15A2: Rear section teeth 20:Joystick 20A: Box Department 20B:Spring 20C: Claw 21: Spring hook part 25: buckle 30: Single side spring 31: First spring hook 32:Second spring hook 35:Fixing bolts 45:Itabe 45A:Screw hole 50:Roller part 51:Small roller 52:Roller falling off prevention part 60: wheel mold 61: Wheel mold groove part 61A: First wheel mold groove part 61B: Second wheel mold groove part 61B1: Flat part 61B2: Arc part 100:Pipe bending machine

Figure 1 is a top perspective view of the pipe bending machine (with the wheel mold installed). Figure 2 is a top perspective view of the pipe bending machine (without the wheel mold installed). Figure 3 is a bottom perspective view of the pipe bending machine (the joystick is closed). Figure 4 is a bottom perspective view of the pipe bending machine (with the joystick open). Figure 5 is a diagram illustrating the operation of the ratchet mechanism. Figure 6 is a front view of the wheel mold (embodiment). Figure 7 is a front view of the wheel mold (comparative example). Figure 8 is a front view of the wheel mold (variation).

Domestic storage information (please note in order of storage institution, date and number) without

Overseas storage information (please note in order of storage country, institution, date, and number) without

10:Machine body

10B: Guidance ditch

10C: Groove for plate installation

11: Flat part of body

15:Press out rod

20:Joystick

25: buckle

35:Fixing bolts

45:Itabe

45A:Screw hole

50:Roller part

51:Small roller

52:Roller falling off prevention part

60: wheel mold

61A: First wheel mold groove part

61B1: Flat part

61B2: Arc part

100:Pipe bending machine

Claims (13)

A pipe bending machine is a pipe bending machine for bending coated pipes, and is characterized by: push out stick; A wheel mold that is installed at the front end of the aforementioned push rod and is formed with a wheel mold groove portion that is clamped into the aforementioned covered pipe when bending the pipe; and, A pair of left and right roller parts support the covered pipe when bending the pipe. The pipe bending machine as claimed in claim 1, wherein the aforementioned wheel mold groove portion has: The first wheel mold groove portion is formed into a tapered shape; and, The second wheel mold groove portion has a connecting groove portion connected to the first wheel mold groove portion, and the width of the connecting groove portion is larger than the outer diameter of the pipe included in the covered pipe. The pipe bending machine according to claim 2, wherein when the width of the connecting groove is defined as W and the outer diameter of the pipe is defined as R, the difference between the width W and the outer diameter R is 5 mm or more and 20 mm. Within. The pipe bending machine according to claim 2 or 3, wherein the second wheel mold groove portion has an arc groove portion connected to the connecting groove portion and having a curvature radius substantially the same as that of the pipe. The pipe bending machine according to claim 1, wherein the wheel mold is formed into a substantially semicircular shape when viewed from above; Furthermore, the wheel mold groove portion is formed along the outer edge of the wheel mold. The pipe bending machine according to claim 1, wherein the roller part is composed of a plurality of small rollers stacked up and down; Furthermore, the plurality of small rollers can rotate independently using a common shaft portion extending in the up-down direction as a rotation axis. The pipe bending machine according to claim 6, wherein a gap is formed between the rotating shaft and each of the small rollers. The pipe bending machine according to claim 1, having a plate portion extending in a direction substantially perpendicular to the longitudinal direction of the extrusion rod; Furthermore, the roller part is fixed to the plate part. The pipe bending machine according to claim 1, wherein the extrusion mechanism of the extrusion rod is a ratchet type. The pipe bending machine as claimed in claim 9, has a joystick, and the joystick is connected to the aforementioned pressing mechanism; Then, the lever is rotated from the open position to the closed position to extend the push-out rod. The pipe bending machine according to claim 10, further comprising an energizing member that energizes the joystick from the closed position toward the open position. The pipe bending machine according to claim 1, wherein the covered pipe is composed of a pipe and a heat-insulating coating material covering an outer periphery of the pipe. The pipe bending machine according to claim 1, wherein the wheel mold is detachably mounted on the front end of the joystick.