GB2033238A

GB2033238A - Hockey Stick

Info

Publication number: GB2033238A
Application number: GB7936531A
Authority: GB
Original assignee: INPLAST HANDELS GmbH; Chemische Werke Huels AG
Current assignee: INPLAST HANDELS GmbH; Huels AG
Priority date: 1978-10-20
Filing date: 1979-10-22
Publication date: 1980-05-21
Also published as: GB2033238B; DE2845735A1; ES8101393A1; CH641053A5; BE879531A; ES254743U; FR2439029A1; ES485214A0; FR2439029B1; ES254743Y; ES251793U; ES251793Y; IN151922B; NL7907767A

Abstract

The hockey stick has a head portion 1 with a rounded depression 3 on the impact face for improving ball control. A method of making such hockey sticks from glass fibre reinforced foam is also disclosed. <IMAGE>

Description

SPECIFICATION Hockey Stick The present invention relates to a hockey stick.

According to a first aspect of the invention, there is provided a hockey stick having a grip portion, a shaft portion and a head portion wherein said head portion has an impact face formed with an elongate rounded depression.

In an advantageous embodiment of the hockey stick, the shaft portion between the head and grip portions is of substantially constant width greater than that of the grip portion.

In a further advantageous embodiment the invention provides that the density of the material varies from one portion of the hockey stick to another. The hockey stick is advantageously constructed such that the density of its material is greater in the head portion than in the grip portion.

This offers the advantage that the hockey stick accumulates a greater amount of kinetic energy in its stroke, so as to confer an increased acceleration on a struck ball.

The material of the hockey stick may advantageously consist of a foamed synthetic material reinforced with glass fiber. This composition results in a number of essential advantages. The employ of a synthetic material adapted to be foamed in suitable forms permits economical mass-production of the hockey stick. Since the working conditions in mass-production can be kept constant, it is ensured that the sticks produced have identical properties.

The synthetic material is preferably a high-molecular polyamide. The known advantageous properties of polyamides, such as their very high strength, are thus conferred upon the hockey stick.

It is of further advantage to select a polyamide having a relative solution viscosity greater than 2.0. A polyamide of this type has particularly good processing properties.

The proportion of the glass fibers in the material is preferably greater than 20% in the form of chopped glass fibers having an average length of more than 0.4 mm. This offers the advantage that the properties such as strength, being resiliency and impact resistance are improved and that the mixture of polyamide and glass fibers is readily injected into the foaming form.thanks to the short lengths of the chopped fibers.

Preferably a suitable plasticizer is added in an amount of more than 0.5%. This results in the material losing its brittleness and obtaining sufficient ductility.

The material employed preferably has the following mechanical properties: 1. Bending strength 2 Ed . DIN 53452 N/mm2 > 180 2. E-modulus (blending) DIN 53 457 N/mm2 > 7000 3. Impact resistance at 230C DIN 53 453 mJ/mm2 > 65 4. Impact resistance at 230C double-V notch 450C DIN 53 453 mJ/mm2 > 25 5. Good damping of impact loads.

The properties of the material defined by the above listed numerical values make the material appear more suitable than wood for the construction of hockey sticks.

According to a second aspect of the invention, there is provided a method of making a hockey stick according to the first aspect of the invention, wherein said hockey stick is manufactured by a foaming process in a mould cavity.

In an advantageous embodiment of the method, the invention provides the employment of a foaming agent in an amount of 0.1 to 1%. This results in optimum foam formation being achieved.

In the preferred practice of the method according to the invention, the mixture of synthetic material and glass fibers is introduced into mould and caused to foam therein in such a manner that the material of the resulting hockey stick has its highest density in the head portion and its lowest density in the grip portion.

Further characteristics of the invention will become evident from the following description given by way of example of two embodiments in conjunction with the accompanying drawings, in which: Figure 1 shows a first embodiment of a hockey stick having a depression in its impact face, Figure 2 shows a second embodiment of a hockey stick having a depression in its impact face and a shaft portion of increased width, and Figure 3 shows a cross-sectional view of the head portion of the hockey stick shown in Figure 1 taken along the line IV-lV therein.

The first embodiment of a hockey stick shown in Figure 1 has a head portion 1, the impact face 2 of which is formed with an elongate rounded depression 3. A shaft portion 4 extending from head portion 1 narrows gradually towards a grip portion 5. A hockey stick of this configuration may be of plastics or alternatively also of wood.

Figure 2 shows a further embodiment. The head portion 1 of this hockey stick has its impact face 2 likewise formed with an elongate depression 3. The shaft 4 extending between head portion 1 and grip portion 5 is of uniform width. The transition 6 between grip portion 5 and shaft portion 4 is rounded. This offers the player improved playing accuracy in ball handling such as for high flying balls.

This hockey stick may also be made of plastics and/or wood.

Figure 3 shows a cross-sectional view taken along the line lV-lV in Figure 1. Head portion 1 is of substantially arcuate cross-sectional shape due to the depression 3 in its impact face 2. Also shown in Figure 3 is a part of the foam structure 7. This foam structure is formed in a mould cavity. This method results in numerous essential advantages being achieved. A particularly important advantage is to be seen in the fact that all hockey sticks produced by this method are identical in all their properties. In particular it is to be noted that all hockey sticks have the same weight and identical shape, so that a player does not have to readjust his playing technique after changing sticks. Further it is noted that the production of the hockey sticks is speedy and economical.

The embodiments described above with reference to the drawings offer a number of essential advantages. Any hockey balls impinging on the head portion in the depressed area thereof are received in the depression and thus prevented from rebounding in an uncontrolled manner. This constitutes a considerable improvement of the ball guidance by comparison to conventional hockey stick and increases the playing precision.

The invention is not limited to the above described embodiment. Thus it is also possible to make ice hockey sticks of the construction and by the method according to the invention.

Any characteristics and structural details evident from the description and the drawings may be essential to the invention by themselves or in any combination.

Claims

1. A hockey stick having a grip portion, a shaft portion, and a head portion, wherein said head portion has an impact face formed with an elongate rounded depression.

2. A hockey stick according to claim 1, wherein that part of said shaft portion between said head portion and said grip portion is of a substantially uniform width which is greater than the width of said grip portion.

3. A hockey stick according to claim 1 or claim 2, wherein the density of the material of the hockey stick varies from one portion to another.

4. A hockey stick according to claim 3, wherein the density of the material in the head portion is higher than that in the grip portion.

5. A hockey stick according to any one of claims 1 to 4, wherein the material of the hockey stick is a glass fiber reinforced, foamed synthetic material.

6. A hockey stick according to claim 5, wherein said synthetic material is a high-molecular polyamide.

7. A hockey stick according to claim 6, wherein the relative solution viscosity of said polyamide is greater than 2.0.

8. A hockey stick according to claim 5 wherein that said glass fibers are present in a proportion of more than 20%, said glass fibers being in the form of chopped glass fibers having an average length of more than 0.4 mm.

9. A hockey stick according to claim 6, wherein said material contains a suitable plasticizer in an amount of more than 0.5%.

10. A hockey stick according to any one of claims 1 to 9, wherein the material employed has the following mechanical properties:

1. Bending strength DIN 53 452 N/mm2L180

2. E-modulus (bending) DIN 53 457 N/mm2h7000

3. Impact strength at 230C DIN 53453 mJ/mm2 > 65

4. Impact strength at 230C double-V notch 450C DIN 53 453 mJ/mm2 > -25

5. Good damping of impact loads.

11. A hockey stick substantially as hereinbefore described with reference to the accompanying drawings.

12. A method for making a hockey stick according to any of claims 1 to 11 wherein the hockey stick is formed by a foaming process in a mould.

13. A method according to claim 12, wherein a foaming agent is employed in an amount of 0.1 to 1.0%.

14. A method according to claim 12 or claim 13 wherein a mixture of synthetic material and glass fiber is introduced into a mould and caused to foam therein in such a manner that the material of the resulting hockey stick has its highest density in the head portion and its lowest density in the grip portion.

1 5. A method for making a hockey stick according to any one of claims 1 to 11 and substantially as hereinbefore described with preference to the accompanying drawings.