Method for making a plastic molded part

Abstract

A method for making a plastic molded part (12) includes injecting plastic (13) into a foil part (2) with plastic (13) being injected into an injection mold (7) at the rear side of the foil part. The plastic molded part (12) is especially a housing component of a portable handheld work apparatus. The method includes providing a plurality of foil parts (2) in a foil strip (1). Thereafter, the foil strip (1) is positioned in the work region of the injection mold (7). A foil part (2) is taken out of the foil strip (1) utilizing a grabber (6) and is placed in the injection mold (7). Thereafter, the foil part (2), which is placed in the injection mold (7), is back injected with the plastic (13).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described with reference to the drawings wherein:

FIG. 1 is a schematic plan view of a foil strip having partially stamped out foil parts provided for placement in an injection mold;

FIG. 2 shows an embodiment of the foil strip of FIG. 1 with the foil strip having a perforated edge and a positioning mark;

FIG. 3 is a schematic showing the operation of the removal of a foil part from the foil strip of FIGS. 1 or 2 and positioning the foil part in a mold recess;

FIG. 4 is a side elevation view of the arrangement of FIG. 3 in the region of the foil strip with the arrangement including a support, guide rollers as well as an unwind unit and a wind-up unit for the foil strip;

FIG. 5 is a longitudinal section view showing the support of FIG. 4 with details of a punch-out apparatus;

FIG. 6 is a schematic cross-sectional view of the closed injection mold of FIG. 3 with a foil part placed therein and injected plastic; and,

FIG. 7 is an enlarged schematic section view of the plastic part produced in the injection mold of FIG. 6 in the region of the detail VII identified in FIG. 6 including details of the arrangement of the foil part relative to the back injected plastic.

Claims

1. A method of making a plastic form part including a housing part of a portable handheld work apparatus, the method comprising the steps of: providing a foil strip containing a plurality of foil parts;positioning the foil strip in a work region of an injection mold;taking a foil part from said foil strip and placing said foil part in said injection mold utilizing a grabber; and,injecting plastic into said injection mold so as to cause said plastic to be applied to said foil part at the rear side thereof.

2. The method of claim 1, comprising the further steps of: partially punching out at least one of said foil parts from said foil strip while retaining connecting segments which continue to hold the foil part in said foil strip and so cause the remaining regions of said foil strip to form a carrier lattice for said foil part; and,cutting through said connecting segments directly in advance of taking said foil part from said foil strip.

3. The method of claim 2, wherein said connecting segments are severed utilizing said grabber.

4. The method of claim 1, wherein said injection mold is part of an injection mold assembly which includes said grabber, a support and a hold-down device; and, wherein said method comprises the further steps of: holding said foil strip between said hold-down device and said support when taking said foil part from said foil strip; and,separating said foil part from said foil strip.

5. The method of claim 4, wherein said foil part is separated from said foil strip by punching out or tearing out said foil part from said foil strip.

6. The method of claim 1, wherein said foil parts in said foil strip have positioning marks assigned thereto; and, wherein said method comprises the further step of positioning said foil strip utilizing said positioning marks for taking said foil part from said foil strip.

7. The method of claim 1, wherein said plastic is injected into said mold so as to be applied to said foil part on the rear side thereof with said foil part being made of the same plastic material as said plastic injected into said injection mold.

8. The method of claim 7, wherein said foil part and the injected plastic are polyamide.

9. The method of claim 1, wherein said foil part is made of clear plastic printed at least partially on the rear side thereof.

10. The method of claim 9, wherein said rear side of said foil part faces toward the plastic injected into said injection mold; and, wherein said method comprises the further step of applying a bonding agent to said rear side.

11. The method of claim 10, wherein said bonding agent is defined by an applied printing ink.

12. The method of claim 1, wherein said plastic is a plastic colored throughout.

13. The method of claim 12, wherein said plastic is a filled plastic.

14. The method of claim 1, wherein said foil part has a thickness (d) in the range of 14 μm to 200 μm inclusive.

15. The method of claim 14, wherein said thickness (d) is approximately 14 μm.

16. The method of claim 1, wherein said housing part is a plastic molded part and formed by injecting plastic into said injection mold including onto the rear side of said foil part thereby causing said foil part to become part of said plastic molded part; and, the ratio of the thickness (d) of said foil part to the overall thickness (D) of said plastic molded part in the region of the foil part is less than 0.5.

17. The method of claim 1, wherein said injection mold has an essentially smooth surface region and said foil part is placed on said surface region.