WO2010000472A1 - Plastic door closer having inserted metal parts - Google Patents

Abstract

The invention relates to a door closer (1), comprising a housing (2), a closing cylinder (3), a closing shaft (5) perpendicular to the center axis of the closing cylinder (3), and a spring (7), wherein the closing cylinder (3) is disposed in a cylindrical pocket (4), and the closing shaft (5) is disposed in a cylindrical recess (6) in the housing (2), wherein the closing cylinder (3) is in toothed engagement with the closing shaft (5), wherein the spring (7) acts upon the closing cylinder (3), wherein the housing (2) and the closing cylinder (3) are substantially made from plastic, wherein the cylindrical pocket (4) of the housing (2) comprises at least one first metal insertion part (10), and wherein a lateral surface of the closing cylinder (3) is formed at least partially by means of a second metal insertion part (11a, 11b).

Description

 Title: Plastic door closer with inserted metal parts

description

The invention relates to a plastic door closer with metal insert parts.

From the prior art it is known to manufacture a door closer completely made of plastic. However, there are several problems:

Between piston and axle gearing, increased abrasion can be observed with pure plastic design. Furthermore, the Achslagerbuchsen often have strong grooves and in the cylinder space often arises in plastic door closers a paragraph at the end of the piston stroke. Furthermore, oil loss is often observed on the screw plug.

It is therefore an object of the present invention to provide a door closer, which has a long service life with simple and cost-effective production.

The solution of this object is achieved by the features of claim 1. The subclaims show advantageous embodiments of the invention.

Thus, the door closer according to the invention comprises a housing, a closing piston, a direction perpendicular to the central axis of the closing piston closer shaft and a spring. In this case, the closing piston is arranged in a cylindrical pocket and the closer shaft in a cylindrical recess in the housing. Furthermore, the closing piston is toothed with the closer shaft and the spring acts on the closing piston. The housing is essentially made of plastic, with the cylindrical Bag of the housing comprises at least a first metal insert. The closing piston is also essentially made of plastic, wherein the lateral surface of the closing piston is at least partially formed by a second metal insert.

Through the metal inserts, z. B. liner made of steel or aluminum alloy, the piston runs in a pure metal environment. The known problems of the prior art, caused by the metal-plastic pairing, are thereby turned off. Since the bushing absorbs large loads, a cheap plastic can be selected as a carrier material. Especially in view of the high raw material prices for aluminum and steel, this combination of plastic with metal treads is a particularly efficient solution for a door closer with a long service life.

In an advantageous embodiment, it is provided that the closer shaft consists essentially of plastic, wherein the toothing of the closer shaft is formed of a third metal insert and the toothing of the closing piston is formed of a fourth metal insert. Thus, the closer shaft can be made of inexpensive plastic with effective teeth made of metal. Of course, the second metal insert part of the lateral surface of the closing piston and the fourth metal insert part for the toothing of the closing piston can be constructed in one piece.

Furthermore, it is provided in an advantageous embodiment that the first metal insert part of the cylindrical pocket comprises an internal thread for screwing a locking screw. The metal thread mating is more tight against oil loss and can hold a higher oil pressure. It is particularly advantageous to overmold the metal insert parts with the plastic. By encapsulating inserts composite parts are produced, which in normal injection molding, for. B. due to the integration of functions in plastic, often can not be produced. The result is composite parts in which different materials are combined together with the plastic. The reason for producing such combinations is the combination of differing properties in terms of strength, conductivity, insulation or weight. For bulky inserts that can be fixed only insufficiently in a closing from bottom to top positive fit, special vertical designs of an injection molding machine must be provided. These are equipped with a fixed vertical locking system, which remains constant during the advance movement. In plastic injection, inserts are inserted by hand into the mold for smaller quantities (less than 50,000 pieces). For larger quantities this task advantageously takes over a robot. As a result, short cycle times are possible.

It is also advantageous to form at least one metal insert on the side facing the plastic edged to prevent twisting of the metal insert. Consequently, z. B. have a liner in the cylindrical recess of the housing on its outside a hexagon. This hexagon is encapsulated by the plastic and is thus stored against rotation.

It is also advantageous to connect at least one metal insert by means of press fit and / or snap fit and / or ultrasonic welding process with the plastic.

In an advantageous embodiment, at least one metal insert with KIe material, in particular thermally activated adhesives, with the plastic - A -

connected. By means of a thermoactivatable plastic, which is previously applied to the metal part and dried, metallic inserts can be anchored in the injection molded part. In injection molding, the hot plastic melt then triggers the bonding process.

As advantageous materials for the metal inserts steel and / or aluminum is provided or an alloy with these metals.

Further details, advantages and features of the present invention will become apparent from the following description of embodiments with reference to the accompanying drawings.

Show it:

FIG. 1 shows a perspective view of the door closer according to the invention,

FIG. 2 shows a detail view of the door closer according to the invention from FIG. 1,

Figure 3: a detail view of a bushing of Fig. 2, and

FIG. 4 shows the bushing with a locking screw from FIG. 3.

In the figures, an inventive door closer is shown.

As shown in FIG. 1, the door closer 1 according to the invention consists of a housing 2 with a cylindrical pocket 4 and a cylindrical recess 6. Further, a closing piston 3, a screw plug 9 and a spring 7 can be seen. Furthermore, FIG. 1 shows a closer shaft 5 with outer teeth 19 a bearing bushing 8. The closer shaft 5 is rotatably supported by the bearing bush 8 in the cylindrical recess 6. The closing piston 3 slides in the cylindrical pocket 4, the external toothing 19 of the closer shaft 5 being in operative connection with a toothing 18 (FIG. 2) of the closing piston 3.

During assembly, the spring 7 is first pushed into the cylindrical pocket. Then the closing piston 3 is used. The cylindrical pocket 4 is closed on its rear side and thus the spring 7 can act on the closing piston 3. To complete the assembly of the door closer 1 according to the invention, the cylindrical pocket 4 is filled with oil and closed with the screw plug 9.

2 shows a partial view of the door closer 1 according to the invention from FIG. 1. A bushing 10 and the closing piston 3 can be seen here. The closing piston 3 further comprises a front metal ring 11a and a rear metal ring 11b, a central cylindrical surface 12, a front control bore 13, a rear control bore 14 and an inner toothing 18.

The bush 10 was inserted before the injection molding of the housing 2 in an injection mold and thus encapsulated by the plastic. Thus, the bushing 10 forms a running surface for the closing piston 3. In the production of the closing piston 3, three metal insert parts were encapsulated with plastic. The front metal ring 11 a and the rear metal ring 11 b thus slide in the bush 10 in the cylindrical pocket 4. In order to guarantee an abrasion-proof toothing between closing piston 3 and closer shaft 5, the teeth 18 was made in the closing piston 3 as a metal insert. Fig. 3 shows the bushing 10 in detail. In this case, the through hole 16 and the hexagon 15 can be seen. The through-hole 16 is brought into coincidence with the cylindrical recess 6 of the housing during assembly. Thus, the closer shaft 5 can act on the closing piston 3 through the through-bore 16. During manufacture, the bushing 10 is completely encapsulated by the plastic. Thanks to the hexagon 15 then the bush 10 is rotatably mounted in the plastic.

FIG. 4 shows a further view of the bushing 10 with the closure screw 9. An internal thread 17 is provided in the bushing 10. The internal thread 17 is advantageously cut into the bushing 10 before injection-molding of the bush 10 with plastic. For oil-tight sealing of the housing 2, the metal closure screw 9 is screwed into the internal thread 17. Alternatively, it is also possible borrowed to manufacture the plug screw 9 made of plastic, in which case advantageously the external thread of the screw plug 9 is provided as a metal insert.

Thus, the invention shows a way to combine the advantages of metal and plastic within a door closer. Thanks to the plastic, the door closer according to the invention is relatively easy and inexpensive. The use of metal inserts, especially on running surfaces, increases the fatigue strength and precision of the door closer.

LIST OF REFERENCE NUMBERS

1 door closer

2 housings

3 closing pistons

4 cylindrical bag

5 closer shaft

6 cylindrical recess

7 spring

8 bearing bush

9 screw plug

10 bushing

11a, 11b metal rings

12 average cylindrical surface

13, 14 control bores

15 hexagon

16 through hole

17 internal thread

18 internal toothing

19 external toothing

Claims

claims 1. A door closer (1) comprising a housing (2), a closing piston (3), a closing shaft (5) perpendicular to the central axis of the closing piston (5) and a spring (7), wherein the closing piston (3) in a cylindrical Pocket (4) and the closer shaft (5) in a cylindrical recess (6) in the housing (2) are arranged, wherein the closing piston (3) with the closer shaft (5) is toothed, wherein the spring (7) on the closing piston ( 3), wherein the housing (2) and the closing piston (3) are made substantially of plastic, wherein the cylindrical pocket (4) of the housing (2) comprises at least a first metal insert (10), and wherein a lateral surface of the closing piston (3) is at least partially formed by a second metal insert part (11 a, 11 b). 2. Door closer according to claim 1, characterized in that the closer shaft (5) consists essentially of plastic, wherein the toothing of the closer shaft of a third metal insert part (19) is formed and the toothing of the closing piston of a fourth metal insert parts (18) is formed , 3. Door closer according to one of the preceding claims, characterized in that the first metal insert part (10) of the cylindrical pocket (4) comprises an internal thread (17) for screwing in a closure screw (9). 4. Door closer according to one of the preceding claims, characterized in that at least one metal insert part is encapsulated by the plastic. 5. Door closer according to one of the preceding claims, characterized in that at least one metal insert part on the plastic side facing edged (15) is formed to prevent twisting of the metal insert. 6. Door closer according to one of the preceding claims, characterized in that at least one metal insert part is connected by means of press fit and / or snap fit and / or ultrasonic welding process with the plastic. 7. Door closer according to one of the preceding claims, characterized in that at least one metal insert part by means of adhesive, in particular thermally activated adhesive, is connected to the plastic. 8. Door closer according to one of the preceding claims, characterized in that at least one metal insert part made of steel or aluminum.