JPH0232428Y2 - - Google Patents

Description

[Detailed description of the invention] [Technical field of the invention] This invention is based on the movement mechanism of a die or core metal as a pipe bending part forming mechanism in a bent pipe manufacturing apparatus proposed in Japanese Patent Application Laid-Open No. 59-123636. It is about improvement.

[Technical background of the invention and its problems] The conventional method for manufacturing bent pipes is to first extrude a straight pipe material using an extruder, and then to shape the straight pipe material into a desired curved shape. The straight pipe stock is passed through a core bar with dimensions close to the inner diameter of the pipe material, shaped, and then extracted from the core bar to produce a product. After press-fitting into a mold and shaping it, the middle mold can be extracted and used as a product, or the material can be injected using only the outer mold, air,
It was manufactured using an inflation method, etc., in which pressurized fluid such as gas or liquid is sealed. However, these methods have poor workability because they require manual labor and a large number of steps, and since the straight pipe material is bent, the outside of the bent part becomes thin, and when used for pressurized liquid, etc., it can burst from this thin part. There is a risk that
In addition, due to the aging of the mold, core metal, etc., variations in the product occur, and the manufacturing costs of the mold and other parts are high, which has disadvantages that are difficult to obtain economically.

Therefore, a method and apparatus for manufacturing a bent pipe was proposed in Japanese Patent Application Laid-open No. 123636/1983.

This manufacturing method and apparatus include a die and a core metal for extrusion molding a tubular body, and the die or core metal is formed to be movable in a transverse direction with respect to the extrusion direction, and a servo motor is driven according to a program. Either use a device that allows controlled movement of the die or core metal via a drive rod by controlling rotation, and move the die or core metal to make the gap between the die and the core metal uniform all around; Alternatively, the pipe may be made non-uniform to form a straight pipe portion or a curved portion.

However, this device mainly moves the die or core metal in the transverse direction with respect to the extrusion direction of the tubular body, and also moves the die or core metal in the vertical direction with respect to the extrusion direction of the tubular body. Mobility means have not been specifically resolved. In addition, when forming a bent pipe of any shape that changes three-dimensionally, the die is separately cut in a direction intersecting the horizontal direction at a desired angle corresponding to each three-dimensional angle to be formed. Alternatively, a plurality of drive rods are provided so that the core metal moves, and these drive rods are operated. Therefore, the mechanism is very complicated, and the bumps in the transmission mechanism when transmitting the driving force have an adverse effect on the movement of the core metal, which requires very precise operation. Furthermore, in order to form a bent pipe with diversified three-dimensional angles, a large number of driving rods must be provided, so depending on the shape of the bent pipe, it may be impossible to arrange driving rods etc. due to space constraints. It has the disadvantage that it often happens.

[Purpose of the invention] In view of the above-mentioned drawbacks, this invention has a simple structure that allows accurate movement of the die or core metal, and forms bent pipes of all shapes that change three-dimensionally. It was designed with the purpose of making it possible.

[Summary of the invention] In order to achieve the above-mentioned purpose, this invention has a substantially cylindrical die and a core bar inserted into the die, and the material is removed from the gap between the inner periphery of the die and the core bar. In a bent tube manufacturing apparatus that forms a tubular body by extruding and molding the material, and then shapes the bent tube by moving a die or a core metal to make the gap between the gaps uneven in the circumferential direction of the material extrusion port, the die and a core metal so that the die or the core metal can be moved in the vertical and horizontal directions with respect to the extrusion direction of the material, a drive mechanism that operates this movement device, and a drive mechanism that operates the movement device in the vertical and horizontal directions. The drive mechanism includes a control device that operates to enable continuous numerical control of each movement to enable three-dimensional forming of the bent pipe, and the drive mechanism has a transmission device that transmits the drive rotational force of the motor to operate the movement device. The transmission consists of a worm as an input-side conductor and a worm wheel as an output-side conductor.The worm wheel has teeth that mesh with the worm, but instead of teeth that mesh with the worm, a rotating body that engages with the grooves of the worm and rotates around the worm wheel. The present invention consists in that the transmission is pivoted on a surface and has no backlash.

[Embodiment of the invention] An embodiment of the invention will be described below with reference to the drawings.

That is, the reference numeral 1 shown in the figure is a mobile device,
The die 21 of the bent pipe manufacturing device S is fixed, and the core metal 22 is
It is designed to be movable.

The structure of the moving device 1 is such that the fixing frame 4 that fixes the die 21 and the core bar 22 are fixed, and the moving device 1 is movable vertically and horizontally with respect to the extrusion direction in which the material is pushed out from the gap between the die 21 and the core bar 22. A movable frame 5, drive cylinders 10, 11 and drive threaded rods 12, 13 for moving the movable frame 5, a drive mechanism 3 consisting of a transmission 26 and motors 7, 8, and a fixed frame 4 for these. , a moving frame 5, and a base 9 on which the drive mechanism 3 is placed.

The fixed frame 4 is firmly fixed on the base 9. Further, the movable frame 5 is attached to the fixed frame 4 so as to be slidable in the vertical and horizontal directions via each slide bearing 6 and the sliding frame 20. That is, the sliding frame 20 is attached to the fixed frame 4 by the slide bearing 6 so that it can slide only in the lateral direction, and the movable frame 5 is attached to the sliding frame 20 by the slide bearing 6 so that it can slide only in the lateral direction. These structures allow the movable frame 5 to be attached to the fixed frame 4 so as to be slidable in the vertical and horizontal directions.

The drive mechanism 3 includes drive cylinders 10 and 11, drive threaded rods 12 and 13, a transmission 26, and each motor 7 and 8.
The drive cylinder 10 transfers the drive rotational force from the drive rotation shaft 16 of the motor 7 to the drive threaded rod 12 via the transmission 26, the belt 14, and the pulley 15.
(In the case shown, a so-called ball screw is used.) and is moved laterally by the rotation of this drive threaded rod 12. The drive rotational force from the shaft 17 is similarly transmitted to the drive screw rod 13 via the transmission 26, the belt 14, and the pulley 15, and the rotation of the drive screw rod 13 causes the drive screw rod 13 to move in the vertical direction.

As shown in FIGS. 7 and 8, the transmission 26 includes a worm 27 as an input conductor and a worm wheel 28 as an output conductor,
The worm wheel 28 has a rotary body 29, which rotates by meshing with a groove in the worm 27, supported on its circumferential surface instead of teeth that are axially aligned with the worm 27. and,
The worm 27 and the worm wheel 28 are formed so as to mesh with each other via the rotating body 29 as described above. Therefore, this transmission device 26 can be meshed and rotated by the rotary body 29 without having a backlash due to the low meshing frictional resistance, so that very accurate power transmission is possible. In other words, the transmission 26 is free from backlash.

Further, as described above, the fixed frame 4, the movable frame 5, and the drive mechanism 3 are mounted on the base 9, and these are mounted on the upper stage 18 of the base 9. This upper stand 18 is supported by a slide bearing 6 so as to be able to slide appropriately on the lower stand 19 of the base 9, and when the die 21 and the core bar 22 are attached and fixed to the fixed frame 4 and the movable frame 5. This mechanism is designed to facilitate its installation.

Next, numeral 2 in the figure is a control device such as a computer, which is capable of continuously numerically controlling the rotation of each of the motors 7 and 8.

That is, the motors 7 and 8 are both servo motors or the like whose rotation speeds can be controlled, and when moving the moving frame 5 in the lateral direction, the drive cylinder 10 that moves the moving frame 5 in the lateral direction is operated. for that,
The motor 7 that operates the drive cylinder 10 is connected to the moving frame 5.
The control device 2 rotates only a predetermined number of revolutions corresponding to the moving distance of
Controlled rotation by. Further, when moving the movable frame 5 in the vertical direction, the drive cylinder 11 that moves the movable frame 5 in the vertical direction is activated. For this purpose, the motor 8 that operates the drive cylinder 11 is controlled and rotated by the control device 2 by a predetermined number of rotations corresponding to the vertical movement distance of the moving frame 5. And moving frame 5
When moving the movable frame 5 in the diagonal direction, the drive cylinder 10 and the drive cylinder 11 are operated simultaneously to move the moving frame 5 in the diagonal direction. For this purpose, if the motor 7 that operates the drive barrel 10 and the motor 8 that operates the drive barrel 11 are, for example, X in the horizontal direction and Y in the vertical direction, then In order to move at an increasing rate of Y, the control device 2 controls the rotating parts to rotate by a corresponding predetermined number of rotations. Then,
The moving frame 5 moves diagonally at the rate of diagonal A in the above equation.

Then, as shown in FIGS. 5 and 6,
If the die 21 is fixed to the fixed frame 4 by the die base 23 and the core bar 22 is fixed to the movable frame 5 via the core bar holding frame 24, the opening of the core bar 22 can be fixed while the die 21 is fixed. It becomes possible to move the core metal 22 appropriately vertically, horizontally, and diagonally with respect to the material extrusion port 25.

This core metal holding frame 24 is disposed within the die 21 so as to be movable vertically, horizontally, and diagonally with respect to the material extrusion port 25. The die 21 is provided with through holes penetrating into the die 21 on the circumferential surface of the die 21 in the four directions (up, down, left and right). Pushing rods 30 planted in four directions are inserted so as to protrude to the outside of the die 21. By fixing this pushing rod 30 to the moving frame 5, the core bar 22 can be moved.

As a result, when extruding material from the gap between the die 21 and the core metal 22 to form a tubular body, if the core metal 22 is moved laterally as described above, the spacing between the gaps becomes uneven in the horizontal direction. , and on the side where the gap is larger, the wall thickness of the tubular body becomes thicker,
On the side where the gap is smaller, the wall thickness of the tubular body becomes thinner. Therefore, the tubular body becomes a curved tube that is bent laterally, with the thicker wall facing toward the outside of the bend.

Then, if the core bar 22 is moved in the vertical direction, the tubular body becomes a curved tube bent in the vertical direction based on the same principle as described above, and similarly in the case of the diagonal direction, a curved tube bent in the diagonal direction is also formed. It is something. Moreover,
If these core metals 22 are moved appropriately during extrusion molding of the material, a three-dimensionally bent tubular body can be easily formed. If the tubular body must be bent three-dimensionally depending on the shape of the place where the tubular body is installed, the bending can be set in advance and the tubular body can be controlled to bend according to this bending. By continuous numerical control using the device 2, it is possible to continuously create a highly strong tubular body with a thick wall on the outside of the bend on the spot without having to bend it using a conventional core metal. This makes it possible to mold the material.

In this case, the movement of the core metal 22 is limited to the movement of the die 21.
The position when the gap between the core bar 22 and the core bar 22 is made uniform is the zero point, and when forming a straight pipe part, the core bar 22 may be returned to the zero point. Moreover, contrary to the above, the core metal 22 may be fixed and the die 21 moved. In that case, as shown in FIG. 9, the die 21 is fixed to the movable frame 5 and the core metal 22 can be fixed to the fixed frame 4 by changing the design.

[Effects of the invention] According to this invention configured as described above, the substantially cylindrical die 21 and the core metal 2 inserted into the die 21
2, a tubular body is formed by extruding and molding the material in the gap between the inner periphery of the die 21 and the core metal 22, and by moving the die 21 or the core metal 22, the gap between the gaps is changed to a material extrusion port. In a bent pipe manufacturing apparatus S that forms a bent pipe by making the pipe uneven in the circumferential direction of the pipe 25, a die 21 and a core bar 22 are attached to the die 2.
The die 21 or the core bar 22 is provided with a moving device 1 formed to be able to move the die 21 or the core bar 22 in the vertical and horizontal directions with respect to the extrusion direction of the material, and a drive mechanism 3 that operates the moving device 1. Since either one can be freely moved relative to the other, the material extrusion ports 25 can be made non-uniform at desired intervals.

Further, by having a control device 2 that operates to enable continuous numerical control of the vertical and horizontal movements to enable three-dimensional forming of a bent pipe, either one of the die 21 or the core metal 22 can be moved to the other. On the other hand, it is possible to make the material extrusion ports 25 uneven at desired intervals, and the intervals can be set accurately, and if the intervals are appropriately set continuously during extrusion of the material. It becomes possible to easily form a three-dimensionally bent tubular body having a desired shape. Moreover, since there is no need to provide drive rods for each angle for oblique operation as in the conventional device, it is possible to simplify the structure.

The drive mechanism 3 also includes a transmission 26 that transmits the driving rotational force of the motors 7 and 8 to operate the moving device 1.
This transmission device 26 includes a worm 27 as an input conductor and a worm wheel 28 as an output conductor, and the worm wheel 28 has teeth that mesh with the worm 27. A non-bumping transmission 2 in which a rotating body 29 that rotates while meshing with a groove is pivotally supported on the circumferential surface.
6, the gap between the die 21 and the core metal 22 is capable of very accurate power transmission, that is,
The spacing between the material extrusion ports 25 can also be finely adjusted.

This is based on the principle of manufacturing a bent pipe by appropriately adjusting the amount of extruded material by unevenly changing the gap between the die 21 and the core metal 22 when extruding this type of material. In order to adjust the bending condition of the pipe with the gap, it is necessary to make a very delicate gap adjustment, and if you just use a normal reduction gear, there will be a large error due to the bending in forward and reverse rotation, and it will be difficult to bend. However, by using the above-mentioned transmission device 26 without backlash, the error can be greatly reduced, and a bent pipe having a desired three-dimensional bend can be reliably manufactured.

As explained above, this invention has a very simple structure, and can easily, accurately, and continuously bend three-dimensionally bent pipes of any shape by controlling the settings of the control device. This has a practical advantageous effect, such as being adaptable to any production system such as mass production of highly accurate bent pipes or production of a wide variety of products in small quantities.

[Brief explanation of the drawing]

The drawings show an embodiment of this invention; Fig. 1 is a front view, Fig. 2 is a side view, Fig. 3 is a plan view, and Fig. 4 shows the main parts when assembled into a bent pipe manufacturing device. 5 is an enlarged front view of the main parts, FIG. 6 is an enlarged side sectional view of the main parts, FIGS. 7 and 8 are front sectional views of the main parts of the transmission, and FIG. 9 is a different embodiment. It is an enlarged side sectional view of the main part of an example. S...Bent pipe manufacturing device, 1...Movement device, 2...
...Control device, 3...Drive mechanism, 4...Fixed frame, 5
...Moving frame, 6...Slide bearing, 7...
Motor, 8... Motor, 9... Base, 10...
... Drive tube, 11... Drive tube, 12... Drive threaded rod, 13... Drive threaded rod, 14... Belt, 15
...Pulley, 16... Drive rotation shaft, 17... Drive rotation shaft, 18... Upper stand, 19... Lower stand, 20...
...Sliding frame, 21...Die, 22...Core metal, 23...
...Die base, 24...Core holding frame, 25...Material extrusion port, 26...Transmission device, 27...Worm, 28...Worm wheel, 29...Rotating body, 30...Pushing rod.

Claims (1)

[Scope of utility model registration request] It has a substantially cylindrical die and a core metal inserted into the die, and a tubular body is formed by extruding and molding material from the gap between the inner periphery of the die and the core metal. In a bent pipe manufacturing device that forms a bent pipe by moving the gap and making the gap uneven in the circumferential direction of the material extrusion port, a die and a core metal are attached and the die or core metal is moved in the direction of extrusion of the material. a moving device configured to be movable in vertical and horizontal directions;
It consists of a drive mechanism that operates this moving device, and a control device that operates to enable continuous numerical control of the vertical and horizontal movements to enable three-dimensional forming of the bent pipe. It has a transmission device that transmits rotational force to operate the moving device, and this transmission device consists of a worm as an input-side conductor and a worm wheel as an output-side conductor, and the worm wheel engages with the worm. A pipe bent part forming mechanism in a bent pipe manufacturing apparatus, characterized in that the transmission device has a non-buckling transmission in which a rotary body that rotates by meshing with a groove of a worm is supported on the circumferential surface instead of matching teeth.