DE102007041982A1 - Manufacturing vehicle internal door-pull handle as hollow body coated with soft plastic, employs water injection process to form hollow cavity in injection-molding - Google Patents

Abstract

Molding is achieved by water injection. The outer layer (3) of softer plastic is added to the molding (1) using a two-component injection process, or by flooding with a casting elastomer. During the water injection stage, plastic melt is introduced into an injection mold. Water is then injected via a first mold section, so that it forms a hollow channel (7) inside the melt. Surplus melt, together with the fluid, are led out of the cavity via a second mold section, into an adjacent cavity connected to it. Residual fluid is removed from the cavity. The melt is allowed to set, forming a solid molding, which is extracted from the mold. Removal of plastic melt and fluid, is essentially tangential to the flow direction of the plastic melt and fluid, in the forming hollow channel. Melt injection and water injection take place at opposite ends of the forming channel. The water injection stage is carried out twice. The second injection of a fluid, takes place at higher pressure than the first. Water- or gas injection may be employed to make the molding. The hollow body is cooled. To apply the layer of softer plastic, it is displaced. The hollow molding includes a reinforcing internal wall. It is prepared to accept a cover (4). The softer plastic covers the walls up to both ends of the supportive wall. The molding is in the form of a vehicle internal door handle. Through the cover, a joint section is formed. When installed, this forms a notional tangent on the outer contour, which is inclined at preferably less than 30[deg] to the vertical. A projecting flanged strut (5) is inserted into a matching recess of the internal cladding of the vehicle door. An independent claim IS INCLUDED FOR the corresponding plastic molding.

Description

The The invention relates to a method for producing a coated Plastic hollow body as well a plastic molding with the features according to the preambles the claims 1 and 7.

From the DE 10 2005 062 825 A1 It is known to produce a hollow body made of plastic by gas injection. In order to improve the feel of the molding, this is then subjected to a two-component injection molding or flooded with a cast elastomer. In this way, the molding is overmolded or coated with a soft component. The gas injection and the application of the surface layer take place in a quasi-continuous process. It is only after the gas injection process waited until the plastic has achieved sufficient strength or rigidity by a sufficient cooling time. Here, the time of converting the molding from one tool to another can also be used for cooling.

task it is now to improve such a manufacturing process and to provide an improved molding.

These Task is with the features of claim 1 and those of the claim 7 solved.

advantageous embodiments can be found in the subclaims.

Of the Invention is based on the core idea, a plastic molding by means of a water injection and with a second, To soften softer material for the purpose of achieving a softer feel. By this measure can Cycle times are significantly reduced in the manufacturing process, because water is the plastic that solidifies in the mold much more effective cooling as gas. Because of the incompressibility of water results for the manufacturing process an improved process control addition, water is against gases such as nitrogen more cheaply available.

All in all elevated thus the visual appearance of the molding. It will achieved a haptic appealing molding, in particular as Handle element for Motor vehicle doors, especially as a handle or Zuziehgriff used can.

The dependent claims have advantageous embodiments of the water injection method. This is also on the DE 10 2004 058 058 A1 referenced and included the entire Offenbahrungsgehalt this document.

highlight However, the design of a plastic molding, which is preferred manufactured by water injection technique and with the features according to claims 8 to 12 in particular with regard to easy mountability on the one hand and improved ergonomics for vehicle users on the other hand is further developed.

For ergonomics and the visual appearance of great importance is a development according to claim 8, after the preferred one by water injection - but possibly also by gas injection - generated Hollow channel two outer, in Has an angle to each other arranged walls, whose the Angle facing away by at least one acting as a reinforcing rib supporting wall connected to each other. This is right-angled or acute-angled converging walls are to improve the feel covered with the second softer plastic layer. It extends the second softer plastic layer at least up to the both ends of the stiffening rib connecting the walls. Prefers this stiffening rib is also for receiving a cover panel prepared, for example, by Verklipsung or other Verrastungselemente is attachable to the plastic molding. In particular, the combination in the claims 8 and 9 given characteristics ensures that the resulting from the further plastic layer and the covering element resulting joint profile are arranged so can that with a designed as Zuziehgriff plastic molding the potential hand contact surfaces be executed with a seamless and therefore haptic pleasant surface can. About that In addition, this area can also be kept more easily because Gripping caused by grip contact from a plane area easier to remove than out of a joint.

In combination with very good haptic properties, a visually outstanding appearance is obtained, in particular, if the course of the joint between the further plastic layer and the cover element is designed so that, in an installation position (with X-axis in vehicle longitudinal direction, Y-axis in vehicle transverse direction and Z-axis). Axis perpendicular to the two aforementioned axes as the vehicle vertical axis) Zuziehgriff the joint on the outer contour of the closing handle defines an imaginary tangent which is inclined by the vertical (Z axis) by a maximum of 45 °, but preferably less than 30 °. For a substantially oval or circular shaped cross-section of the closing handle, this results in a joint profile that runs essentially outside the potential hand-contact region between the hand and the closing handle. In addition, in a joint surrounding the cover, another joint section are laid in an invisible to the vehicle occupant area, so that in this way Zuziehgriffe be presented with high quality design.

A good mountability with high load capacity arises according to claim 12 in that on the plastic molded part one from the cover and / or the further plastic layer outstanding sword-like Flange part is formed, which in a corresponding receiving portion an inner lining inserted and there by positive engagement or Screw connections can be attached. This sword-like Flange part is preferably designed with stiffening ribs and preferably has no hollow channel, so that the latter based on the Overall requirements for the component closing handle to be kept as small as possible and thus the manufacturing process is as stable as possible manageable.

One preferred embodiment the invention is shown in the drawing. It shows

1 as a coated plastic hollow body a buildable in a vehicle door Zuziehgriff in installation position, shown as a plan view of the vehicle transverse direction

2 : a view according to section II-II in 1 and

3 in a perspective view of the potential view of a vehicle occupant on a pull handle in installation position.

One recognizes in 1 as a coated plastic molding a total with 1 designated Zuziehgriff whose essential elements here is a body 2 from a first sprayable plastic component (for example ABS or PC) and a second softer plastic layer 3 (For example, TPU) of a second plastic component and a cover 4 are. Material uniform component of the further plastic layer 3 and the cover member 4 partially covered basic carrier 2 is a sword-like flange part 5 , in a here with dashed lines indicated door interior trim part 6 a vehicle not shown here is plugged.

2 shows a preferably by water injection - but possibly also by gas injection - produced hollow channel 7 which here essentially by two outer, arranged at an angle to each other walls 8th and 9 is limited, the corners facing away from the angle 10 and 11 by at least one support wall acting as a stiffening rib 12 connected to each other. The here two-layered cover 4 is on the body 2 for example in the area of the supporting wall 12 fastened by clipping and forms at least in the area of a potential hand contact zone together with the further plastic layer 3 a butt joint section 13 , to the outer contour of Zuziehgriffes 1 mentally a tangent T is created. The butt joint section 13 is on the circumference of here in cross section oval Zuziehgriffs 1 preferably moved to a location that leads to the tangent to an orientation that is inclined at most by 45 °, but preferably by less than 30 ° relative to the vertical, ie the Z-axis. This will ensure that the butt joint section 13 outside the potential hand contact zone of the vehicle occupant.

To illustrate this fact is schematically with dash-dotted lines the end of a human hand 14 indicated. One recognizes in 2 too, that the soft plastic layer 3 over the supporting wall 12 out to a lower area 15 of the basic body 2 is inserted, so that between the cover 4 and the soft plastic layer 3 another joint section 16 results, which is not recognizable from the normal sitting position of the vehicle occupant out.

From the illustration in 3 is still a fortification dome 17 seen in common with the sword-like flange 5 ensures that the pull handle 1 with ease of mounting solid with the door interior trim 6 of the vehicle not shown here can be connected. Of particular importance here is that the design of the hollow channel 7 is designed so that this only in the area below the soft plastic layer 3 and thus not explicitly in the lower flange part 5 is led into it. In this way, the length of the hollow channel for the closing handle 7 minimized, minimizing cycle time and increasing process reliability. The extent of the hollow channel 7 in other words, to those areas of the closing grip 1 limited to representing an excellent feel necessarily with the soft plastic layer 3 to be covered.

Claims (12)

Process for producing a coated hollow body ( 1 ) made of plastic, the body ( 1 ) is formed by means of an injection process and is applied to at least a part of the outside of the hollow body ( 1 ) at least one layer ( 3 ) is applied from a softer plastic, characterized in that the shaping is carried out by means of water injection. Method according to claim 1, characterized in that the layer ( 3 ) is applied from softer plastic by two-component injection molding or by flooding with a casting elastomer. A method according to claim 1 or 2, characterized by the following steps for the water injection method: (a) introduction of a plastic melt into a contour of the hollow body to be produced ( 1 ) at least partially imaging cavity of an injection mold; (B) injection of water over a first gate of the injection mold into the introduced plastic melt, so that by the penetrating liquid a hollow channel ( 7 ) is formed within the melt and the excess plastic melt is discharged together with the liquid via a second gate from the cavity into a side cavity connected thereto; (c) applying the residual liquid from the cavity; (d) allowing the plastic melt to solidify until a solid molding is formed; (e) demolding of the molded part from the cavity of the injection mold, (f) wherein the discharge of the plastic melt and the liquid substantially tangential to the flow direction of the plastic melt and the liquid in the forming hollow channel ( 7 ) he follows. A method according to claim 3, characterized in that the injection of the plastic melt and the injection of water substantially at opposite ends of the forming hollow channel ( 7 ) respectively. Method according to one of claims 3 or 4, characterized that step (b) is applied twice, the liquid is applied at the second application with a higher pressure than at the first application. Method according to one of the preceding claims, characterized in that the hollow body ( 1 ) at least partially cooled and for the application of the layer ( 3 ) is made of softer plastic. Plastic molding with a hollow channel ( 7 ) having at least a part of its outside a second softer plastic layer, characterized in that this is formed by means of a water injection method or gas injection method. Plastic molding according to claim 7, characterized in that - the hollow channel ( 7 ) two outer, at an angle to each other arranged walls ( 8th . 9 ), whose ends facing away from the angle ( 10 . 11 ) by at least one effective as a stiffening rib support wall ( 12 ), - the walls ( 8th . 9 ) through the second further plastic layer ( 3 ) at least up to the two ends of the support wall ( 12 ) are covered. Plastic molding according to claim 8, characterized in that the support wall ( 12 ) for receiving a cover element ( 4 ) is prepared. Plastic molding according to at least one of claims 7 to 9, characterized in that it in the shape of a Zuziehgriffes ( 1 ) is formed for a vehicle door. Plastic molding according to claim 10, characterized in that by the cover ( 4 ) the further plastic layer ( 3 ) a joint section ( 13 ) is formed, which in a mounting position in the Zuziehgriff ( 1 ) defined on the outer contour of an imaginary tangent T, which is inclined about the vertical (Z-axis) a maximum of 45 °, preferably less than 30 °. Plastic molding according to at least one of claims 10 or 11, characterized in that on a base body ( 2 ) of the plastic molding a from the cover ( 4 ) and / or the further plastic layer ( 3 ) outstanding sword-like flange part ( 5 ) is formed, which in a corresponding receiving portion of an inner lining ( 6 ) of a vehicle door can be inserted.