JPH0361020A - Blow molding method of seat frame for automobile - Google Patents

Abstract

PURPOSE:To mold a seat frame excellent in quality, by a method wherein a reinforcement frame constituted by forming a plurality of air circulation holes in an outer circumferential part and a positioning fitting part communicating with its hollow part on the lower end part is inserted within parison by connecting with an air nozzle. CONSTITUTION:A reinforcement frame 2 is obtained by bending and forming a metallic hollow pipe into almost a rectangular framelike state and air discharge holes 27 communicating with a hollow part 26 of the reinforcement frame 2 are formed on the inside part of almost a U-shaped upper frame 25 at fixed intervals. A fitting cylinder part 29 which is in almost cylindrical state is formed on almost the central part of the lower part in almost a linear state by projection downward. Then the reinforcement frame 2 is inserted for arrangement into a fixed position of the inside of a contracted space 19. Pressurized air is injected into an expanded space 18 through an air feed nozzle 21 with a pinching device 24 under a state where the lower end part of parison 3 is closed in almost an airtight state. Then air in the contracted space 19 is discharged from a discharge nozzle 22 through the reinforcement frame 2 having the air discharge hole 27 and hollow part 26 and the parison 3 is preblown.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method of blow molding a synthetic resin automobile seat frame reinforced with a reinforcing frame.

[Prior art]

Generally, the molding method for molding a hollow synthetic resin frame involves extrusion molding a parison made of synthetic resin such as polyethylene or polypropylene, and blow molding by expanding this parison with air in the molding cavity of a mold. Molding methods are known.

Normally, frames formed by the above blow molding method have relatively low strength and rigidity, making it difficult to apply them to automobile seat frames, etc. In recent years, in order to solve this problem, synthetic Many techniques have been proposed for reinforcing a resin frame with a metal reinforcing frame.

For example, Japanese Utility Model Application Publication No. 62-75916 discloses that a substantially cylindrical parison made of synthetic resin and a substantially rectangular metal reinforcing frame disposed outside the parison are installed in a molding cavity of a mold. After the mold is clamped, pressurized air is injected into the parison to inflate the parison, and the parison at the outer edge of the seat frame wraps around the reinforcing frame, forming a reinforcing frame inside the seat frame. A buried blow molding technique is described.

In the above-mentioned blow molding technology, the mold is provided with a support bracket that supports the reinforcing frame, or a supporting rond that can be raised and lowered is provided below the mold, and the lower end of the reinforcing frame is connected to the end of this supporting rond. , the reinforcing frame can be accurately joined to the predetermined position of the seat frame J, but since the viscosity of the parison is usually relatively high and the blowing pressure is relatively low, the reinforcing frame may not be completely wrapped in the parison. There are problems in that areas with poor adhesion occur and the joint strength decreases, and dents are formed in the areas with poor adhesion, impairing the appearance of the frame member.

Therefore, for example, in Japanese Patent Application Laid-open No. 134225/1983,
The reinforcing frame is configured to be expandable and retractable with a plurality of split frames, and an inflatable and deflated bag body connected to the reinforcing frame and an air supply nozzle is set inside a roughly cylindrical parison made of synthetic resin, and a mold is formed. After tightening, pressurized air is injected into the bag to inflate the bag, and the parison is expanded through the bag, and the reinforcing frame is held by the guide groove on the outer periphery of the bag to attach the reinforcing frame J to the parison. A blow molding technique is described in which the reinforcing frame is crimped at a predetermined position to join the reinforcing frame to the inner wall of the seat frame.

[Problem to be solved by the invention]

In the latter blow molding technique, the reinforcing frame is joined to the inner wall of the seat frame, so even if poor adhesion occurs between the reinforcing frame and the seat frame, no dents will be formed on the surface of the seat frame. Since the reinforcing frame is positioned by the guide groove of the bag, it is difficult to accurately join the reinforcing frame at a predetermined position.

Moreover, the joint area between the reinforcing frame and the frame member is relatively small, making it impossible to obtain sufficient joint strength.

On the other hand, when the reinforcing frame is not divided in the latter blow molding technique, the reinforcing frame is inserted into the parison through the support ronds as in the former blow molding technique, and is accurately positioned and supported at a predetermined position. Although it is possible to do so, there is a problem in that it requires a support rod and a lifting mechanism for raising and lowering it, which complicates the structure of the blow molding apparatus.

An object of the present invention is to provide a blow molding method for an automobile seat frame that allows a reinforcing frame to be inserted and arranged in a predetermined position inside a parison with high accuracy without complicating the configuration of a blow molding device.

[Means to solve the problem]

A blow molding method for an automobile seat frame according to the present invention is a blow molding method in which a hollow synthetic resin automobile seat frame reinforced with a reinforcing frame is blow molded using a blow molding device. A plurality of air circulation holes are formed on the outer periphery of the reinforcing frame, a positioning fitting part is formed at the lower end of the reinforcing frame that communicates with the hollow part, and the end of the air nozzle is fitted into the positioning fitting part described in 2. A reinforcing frame is connected and inserted into the extruded synthetic resin parison through an air nozzle, and air is sucked in from the air nozzle through the reinforcing frame when the parison is blow-molded after the mold is closed. or supply.

[Effect]

In the method for blow molding an automobile seat frame according to the present invention, a plurality of air circulation holes are formed in the outer circumference of a hollow reinforcing frame, and a positioning fitting part is formed in the lower end of the reinforcing frame and communicates with the hollow part. The reinforcing frame is connected to the end of the air nozzle by fitting its positioning fitting part to the end of the air nozzle, and in this state, it is precisely inserted into the predetermined position inside the extruded synthetic resin parison through the air nozzle. will be established. After the mold is clamped, air is sucked or supplied from the air nozzle through the air circulation holes and hollow portions of the reinforcing frame, and a seat frame reinforced with the reinforcing frame is molded.

The seat frame formed as described above has a reinforcing frame joined to the predetermined position with high accuracy, and is of good quality.

In addition, when molding a seat frame by sucking the air inside the parison, the reinforcing frame 1 is completely wrapped in the parison that constitutes the sucked space, with almost no gaps, and the resin part of the molded seat frame is reinforced. The frame is embedded integrally.

〔Effect of the invention〕

According to the professional molding method for automobile seat frames according to the present invention, as detailed in the above [Operation] section, existing equipment can be replaced by simply connecting the reinforcing frame to the air nozzle and inserting it inside the parison. It becomes possible to insert and arrange the reinforcing frame into a predetermined position inside the parison with high accuracy by effectively utilizing the air nozzle without making any changes, and it becomes possible to mold a high-quality seat frame.

In addition, when forming the seat frame by suction,
Since the reinforcing frame is integrally buried in the resin part of the sorting frame with almost no gaps, the bonding strength of the reinforcing frame can be greatly improved.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

In this embodiment, the present invention is applied to a blow molding method for a seat hack frame for an automobile seat reinforced with a metal reinforcing frame.

First, the configurations of the blow molding device 1 and the reinforcing frame 2 will be explained.

The blow molding device 1 includes an extrusion device 4 that extrudes the parison 3, and a blow molding section 5 that is disposed below the extrusion device 4 and blow molds the extruded parison 3, and is configured as follows. .

To explain the extrusion device 4, as shown in FIGS. 1 and 2, a vertically oriented slide core 9 is movably mounted approximately in the center of the accumulator head 6. On the outside of the slide core 9 is a generally cylindrical storage chamber 8 that can accommodate one shot of synthetic resin material 7, and in the upper half of the slide core 9 is a generally cylindrical storage chamber 8 that can pressurize the inside of the storage chamber 8. A shaped piston member 10 is movably mounted, the middle part of the piston member 10 is airtightly mounted to the upper end of the accumulator head 6, and above the accumulator head 6 is a hydraulic cylinder that drives the piston member 10 in the vertical direction. 11 is provided, and a material supply cylinder 12 of a material supply device (as shown) for supplying the resin abrasive material 7 into the storage chamber 8 is connected to the vicinity of the upper end of the accumulator hendro.

A substantially annular first extrusion passage 13 with an open lower end communicating with the storage chamber 8 is provided between the lower end of the slide core 9 and the lower end of the accelerator door 6, and a lower end opening is provided near the lower end of the slide core 9. The second extrusion passage 14 is forced forward and backward, and both front and rear ends of the second extrusion passage 14 are connected to the storage chamber 8 and the first extrusion passage 14.
When the piston member 10 is communicated with the extrusion passage 13 and is driven downward by the hydraulic cylinder 11, the synthetic resin material 7 filled in the storage chamber 8 passes through the first extrusion passage 13 and the second extrusion passage 14 to the accumulator head 6. pushed out from
Parison 3 is molded.

As shown in FIGS. 1 and 3, the parison 3 is
The cylindrical parison 15 which is extruded from the extrusion passage 13 and the partition parison 16 which is approximately flat and which is extruded from the second extrusion passage 14 and divides the interior of the cylindrical parison 15 into two chambers are integrally attacked. The parison left half 15a and the parison right half 15b of the cylindrical parison 15 and the partition parison 16 form a contraction space 19 (either one of (corresponding to the space) and the expansion space 18 (corresponding to the other spaces) are attacked.

The blow molding section 5 is for blow molding the extruded parison 3, and as shown in FIGS. A pair of left and right molds 20 that can sandwich the upper and lower ends near each other are disposed, and a parison 3 is disposed at the lower end of both molds 20.
A pinch device 24 that can pinch the vicinity of the lower end of the
Between both molds 20, there is an air supply nozzle 21 connected to an air supply device (as shown) and capable of supplying pressurized air into the expansion space 18, and an air supply nozzle 21 connected to an air discharge device (as shown). An air discharge nozzle 22 capable of discharging the air within one contraction space, and a pair of expander pins 23 inserted into the rain spaces 18 and 19 and expanding the parison 3 in the front and back direction as shown in FIG. The nozzles 21 and 22 and the expander pin 23 are driven up and down by a lifting device (not shown) to a blow position in which they are moved into the vicinity of the lower end of the parison 3 and to a retracted position in which they are moved below the parison 3.

The reinforcing frame 2 is a metal hollow pipe bent into a substantially rectangular frame shape, and as shown in FIGS. 1, 5, and 6, the inner side of the substantially U-shaped upper frame 25 is Air discharge holes 27 communicating with the hollow portion 26 of the reinforcing frame 2 are formed at predetermined intervals, and a substantially cylindrical fitting cylinder portion 29 is formed in the substantially central portion of the substantially linear lower frame 28 and is directed downward. It is formed protrudingly.

A fitting part 22a is formed at the upper end of the air discharge nozzle 22 and is removably fitted into the fitting cylinder part 29.The fitting cylinder part 29 is inserted into the fitting cylinder part 29 from below in the vicinity of the upper end of the air discharge nozzle 22. An annular flange 22b is formed to hold the receiver, and an annular seal link 30 is fixed to the second side of the flange 22b, with which the lower end of the fitting cylinder 29 contacts in a substantially airtight manner, and the reinforcing frame 2 is fixedly supported at the upper end of the air discharge nozzle 22 via the fitting cylinder portion 29, and its hollow portion 26 communicates with the air outlet at the upper end of the air discharge nozzle 22 in a substantially airtight manner via the seal ring 30. be done.

Next, a method of blow molding the seat back frame 31 using the blow bottom forming device 1 described in "2" will be explained.

First, the synthetic resin material 7 heated and melted at 200 to 300°C in the material supply cylinder 12 is filled into the storage chamber 8.
With the mold 20 opened, the hydraulic cylinder 11 is driven to pressurize the synthetic resin material 7 in the storage chamber 8 with the piston member 10, and the parison 3 is extruded between the molds 20.

Next, the fitting cylinder part 29 is attached to the fitting part 22a, and the reinforcing frame 2 is attached to the upper end of the air discharge nozzle 22 (=t &:
1) Position the reinforcing frame 2 and connect the air discharge port of the air discharge nozzle 22 to the hollow portion 26.

Next, as shown in FIGS. 1 and 4, the expander pin 23 is inserted into the spaces 18 and 19 from below, and then the expander pin 23 is moved horizontally to push the lower end of the parison 3 in the front and back direction. In this state, the air supply nozzle 21 and air discharge nozzle 22 are raised to the blow position, and the air supply nozzle 21 is inserted into the expansion space 18, and the reinforcing frame 2 is moved through the air discharge nozzle 22 into the contraction space 19.
Insert and arrange it at a predetermined position inside.

Next, as shown in FIG. 7, while the lower end of the parison 3 is closed in a substantially airtight manner using the pinch device 24, the air supply device is driven to inject the air from the air supply nozzle 21 into the expansion space 18.
Pressurized air of ~6 atmospheres is injected, and the air exhaust device is driven to discharge air from the air exhaust nozzle 22 to the contraction space 1 through the reinforcing frame 2 having the air exhaust hole 27 and the hollow part 26.
Exhaust the air in 9 and pre-blow parison 3. As a result, the right half of the parison 15b expands, and
The left half of the parison 15a contracts, and the reinforcing frame 2 is wrapped around the third left half of the parison 15a and the partition parison 16.

Next, as shown in FIG. 8, after the mold 20 is clamped, pressurized air is injected from the air supply nozzle 21 into the expansion space 18 and from the air discharge nozzle 22 into the contraction space. Exhaust the air in 19 and move parison 3 to the main valve. At this time, the cylindrical parison 15 expands along the inner surface of the mold 20 constituting the molding cavity 32,
The partition parison 16 is in close contact with the left half of the parison 15a with almost no gap, and the reinforcing frame 2 is wrapped between the partition parison 16 and the left half of the parison 15a with almost no gap.

Next, the parison 3 is held in the "2" state for a predetermined period of time to harden, and then the mold is opened and unnecessary portions are cut off to obtain the seat back frame 31 shown in FIG.

As shown in FIGS. 9 and 10, in the seat back frame 31 blow-molded as described above, the metal reinforcing frame 2 is inserted into the vicinity of the outer edge of the rear wall of the synthetic resin resin frame 33. Since it is buried with almost no gaps, it is possible to ensure sufficient bonding strength between the reinforcing frame 2 and the resin frame 33, and even if some poor adhesion occurs between the reinforcing frame 2 and the resin frames J and 33, the bonding will be maintained. A resin frame 3 that prevents a significant decrease in strength and contrasts with areas with poor adhesion
No depression or the like is formed on the outer surface of the seat hack frame 31, and the appearance of the seat hack frame 31 is not impaired.

Further, as described above, since the reinforcing frame 2 can be positioned and supported at a predetermined position within the contraction space 19 by also using the air discharge nozzle 22, a separate mechanism for supporting the reinforcing frame 2 is not required. The configuration of the blow molding device 1 can be simplified. Moreover, the contraction space 1 is
Since the air in the upper part of the parison 9 can be reliably exhausted, there is no need to worry about poor adhesion between the left half of the parison 15a and the partition parison 16, and the reinforcing frame J.
, 2 and the resin frames 1 and 33 can be prevented, and the strength and rigidity of the seams 1 to 31 can be improved.

Next, we will discuss a modification of the above blow molding method. I will clarify.

First, the changed parts of the blow molding apparatus 1 will be explained.

As shown in FIGS. 11 to 14, the second extrusion passage 14 and air discharge nozzle 22 of the slide core 9 are omitted, and a substantially cylindrical tube is formed from the first extrusion passage 13A between the lower end of the slide core 9A and the accumulator head 6. A shaped parison 3A is extruded, and an expansion space 18A extending in the extrusion direction is formed inside the molded parison 3A. 21a and a fitting part 21b are formed, and a seal ring 30 is fixed to the upper side of the flange part 21a, with which the lower end of the fitting cylinder part 29 abuts in a substantially airtight manner.
is fitted and connected to the fitting part 21b at the upper end of the air supply nozzle 21A through the fitting cylinder part 29, and the hollow part 26 is connected to the upper end of the air supply nozzle 21A in a substantially airtight manner through the seal ring 30. It communicates with the air supply port.

Next, a method of blow molding the seat hack frame 31A using the blow molding apparatus 1A will be described.

First, the parison 3A is placed in a mold 20 in the same manner as in the above embodiment.
extrusion molding in between.

Next, a decorative frame 2 is attached to the upper end of the air supply nozzle 21A.
Fixed support.

Next, as shown in FIG.
Insert the pair of expander pins 23 from below, and then move the expander pins 23 horizontally to push the lower end of the parison 3A outward by nl''. In this state, raise the air supply nozzle 21A and open the air supply nozzle. The reinforcing frame 2 is inserted into the expansion space 18A at a predetermined position via the reinforcing frame 21A.

Next, pressurized air is injected into the expansion space 18A from the air supply nozzle 21A through the reinforcing frame 2 to perform a pre-blow, and then the mold 20 is clamped and a main blow is performed. Thereby, the reinforcing frame 2 is positioned and supported at a predetermined position inside the parison 3A, and comes into close contact with the inner wall of the parison 3A.

The parison 37A is then held in the above state for a predetermined period of time to harden, and then the mold 20 is opened and unnecessary parts are cut out to obtain a sheet hack frame 318.

In the seat back frame 31A blow-molded as described above, the reinforcing frame 2 is accurately joined to the rear inner surface of the side wall portion of the resin frame 33A, as shown in FIG.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a longitudinal cross-sectional view of a blow molding apparatus, FIG. 2 is a cross-sectional view along the line
The figure is a sectional view taken along the line X-X in Figure 9 before reinsertion of the reinforcing frame, and Figure 4.
The figure is a diagram equivalent to Figure 3 after the reinforcing frame has been inserted, Figure 5 is a perspective view of the reinforcing frame, Figure 6 is a vertical cross-sectional view of the connecting part between the reinforcing frame and the air discharge nozzle, and Figure 7 is a view of the reinforcing frame during pre-blowing. A longitudinal sectional view of the mold and parison, FIG. 8 is a view corresponding to FIG. 7 during main blowing, FIG. 9 is a perspective view of the Sea I hack frame, FIG. 10 is a sectional view taken along the line X-X in FIG. 9,
11 to 16 relate to modified examples, in which FIG. 11 is a section 8 of the blow molding apparatus corresponding to FIG. 1, FIG.
The figure is Figure 11 X TIT-X Ill line sectional view,
Figure 4 is a diagram equivalent to Figure 6, Figure 15 is a diagram equivalent to Figure 4, and Figure 16 is a diagram equivalent to Figure 4.
The figure is a diagram equivalent to Figure 10. 1.IA...Blow molding device, 2..Reinforcement frame,
3.3A...parison, 20...mold, 2LA...
Air supply nozzle, 22... Air discharge nozzle, 22a
・2 ], b... Fitting part, 26... Hollow part, 27
・・Air discharge hole, 29・・Fitting cylinder part, 31・31A
... Sea 1 - Hack Frame. Patent applicant Mazda Motor Corporation 9 Fig. 8 31 Niji-dopack frame 410 Fig. 1 Fig. 13 13A 21b = Drinking name space S

Claims (1)

[Claims] (1) In a blow molding method in which a hollow synthetic resin automobile seat frame reinforced with a reinforcing frame is blow molded using a blow molding device, a plurality of air circulation holes are formed in the outer periphery of the hollow reinforcing frame. A positioning fitting part that communicates with the hollow part is formed at the lower end of the reinforcing frame, and the end of the air nozzle is fitted into the positioning fitting part for communication connection, and an extrusion-molded synthetic resin parison is formed. An automobile seat frame characterized in that a reinforcing frame is inserted into the interior through an air nozzle, and air is sucked or supplied from the air nozzle through the reinforcing frame when blow molding a parison after the mold is closed. Blow molding method.