NL9301607A - Claw hammer - Google Patents

Abstract

The invention relates to a hammer, comprising a shank and a head which consists of a single part, the head comprising a substantially flat striking surface and an at least partly curved nail-pulling surface which is provided with a substantially wedge-shaped cutout, the striking surface extending in a contact surface of the nail-pulling surface. Preferably, at least that part of the nail-pulling surface which is active when used on a flat surface extends through an arc with a descriptive angle of substantially 180 degree. Therefore, if a hammer in which the striking surface extends in a contact surface of the nail-pulling surface is used to pull out a nail, the entire nail-pulling surface can be used to pull out the nails as far as the striking surface, preventing marks or other damage to the material.

Description

CLAW HAMMER

The invention relates to a hammer comprising a shank and a one-piece head, the head comprising a substantially flat striking face and an at least partially curved nail pulling surface provided with a substantially wedge-shaped recess.

Such hammers are commonly known under the name "claw hammer".

Such a hammer is also known from GB-A-117273 and from US-A-4154273.

While such prior art hammers generally perform well as impact tools, when used as nail removal tools, they suffer from the drawback that the nail pull-out is small, so that the hammer has to be moved several times around the nail completely out of the material from which it is to be removed.

With this known tool, when the nail is pulled out over a certain distance, the impact surface of the hammer comes into contact with the material from which the nail has to be removed, which usually causes must-shaped damage due to the relative softness of this material. In general, this is less desirable.

In addition, such known hammers have to be moved a number of times when pulling out a long nail, where there is thus a large pull-out racket, in order to be able to pull out the nail completely.

The object of the present invention is to provide a hammer, wherein the above drawbacks are avoided.

This object is achieved in that the impact surface extends in an interface of the nail pulling surface.

Thus, when a hammer with the impact face extending into an interface of the nail drawing face is used to stretch a nail, the entire nail drawing face may be used to pull the nails up to the impact face, with damage or other damage to the nail. material are prevented.

Preferably, the nail pull surface extends to the impact surface. This measure entails a full and effective use of the nail pull surface.

According to a further preferred embodiment, the nail drawing surface extends over an arc of substantially 180 °. This gives a particularly long pull-out for the nails, which minimizes the number of times the hammer has to be moved. Incidentally, such a large extension of the nail pulling surface is only possible with the measure according to the main claim. Other subclaims relate to other attractive embodiments of the invention, which will be explained in the description.

The present invention will be elucidated hereinbelow with reference to the annexed drawings, in which: figure 1 shows a perspective view of the hammer according to the invention during use as an impact tool; and figure 2 is a perspective view of the hammer according to the invention, in which it is used for pulling out nails.

Figure 1 shows a hammer 1, which is formed by a stem 2 and a head 3. In the present case, the stem 2 is made of wood, but it is equally possible to use a metal stem or a stem of another material, for example of to use carbon fiber reinforced plastic.

The head 3 is formed by a head body 4 which is delimited on one side by the impact face 5 which merges into the adjacent nail pulling surface 6. The nail pulling surface 6, incidentally, has a cylindrical shape. On both sides, the head body 4 is bounded by side surfaces, one side surface, 7 of which is visible.

Furthermore, the head body 4 is bounded by the stem 2 and by a semicircular surface 8. This semicircular surface ensures that the striking surface 5 is rounded on at least one side. The head body 4 continues in the claw 9 which is bounded on one side by the rest of the nail pull surface 6. Thus, the total nail pull surface extends over an arc of a descriptive angle of substantially 180 °. It will be clear that the invention is not limited to an arc of 180 °; it is equally possible to use an arc of, for example, mainly 165 °, 150 °, 135 ° or 120 °.

On the other side, the claw 9 is delimited by an internal face 10. At the distal end of the claw 9, a V-shaped notch 11 is provided which, like claw hammers of the prior art, is used for clamping the nails to be peeled off.

The operation of the hammer according to the invention will now be explained.

As Figure 1 shows, the hammer can be used as a normal impact tool. The striking surface 5 can hereby drive a nail 12 to be driven into a piece of wood 13. The rounding of the striking surface 5 prevents the wood 13 from having to arise during striking as well, as would undoubtedly be the case if the striking surface 5 were rectangular.

Figure 2 shows how the hammer 1 can be used to pull out a nail 14 from a wooden construction 15. The hammer 1 is moved by hand 16 in such a way that the head 17 of the nail 14 is engaged by both halves of the claw 9, and wherein the shank of the nail 14 extends through the wedge-shaped recess 11. By subsequently tilting the stem 1 as a lever, the nail is removed, whereby due to the great length of the nail pulling surface 6, the nail can be pulled out in a single operation.

Since the axis of the stem extends substantially perpendicular to the chord describing the arc, an effective transmission of forces is obtained.

It is further pointed out that with tight-fitting nails, which must be pulled out with great force, it is possible to grip the nail as close as possible to the end of the notch, while, unlike the prior art associated hammers, a sufficient pull-out chain is available.

Furthermore, it is important in the hammer according to the invention that it can be manufactured using conventional hammer manufacturing techniques.

An interesting aspect lies in the fact that the hammer is flat. It often happens that the sides of the hammer are used as a striking surface, for example when joining together sheets of tongue and groove. It is important that the playing surface is flat to avoid the need to create. It is also important in this use that a large striking surface is obtained by the solidity of the head.

Finally, it is important that the hammer has no loose detachable parts; the hammer forms one whole.

Claims (7)

A hammer, comprising a shank and a one-piece head, the head comprising a substantially flat striking surface and an at least partially curved nail-drawing surface provided with a substantially wedge-shaped recess, characterized in that the striking surface extends in an interface of the nail pull plane. Hammer according to claim 1, characterized in that the nail pulling surface extends up to the striking surface. Hammer according to claim 1 or 2, characterized in that at least the part of the nail drawing surface, which is effective on a flat surface, extends over an arc with a descriptive angle of substantially 180 °. Hammer according to claim 3, characterized in that the axis of the stem extends substantially perpendicular to the chord describing the arc. Hammer according to claim 4, characterized in that the axis of the stem substantially intersects the center of the arc. Hammer according to any one of the preceding claims, characterized in that said part of the head between the part of the nail drawing surface over which the wedge-shaped recess does not extend and the center point is substantially solid. Hammer according to any of the preceding claims, characterized in that the side surfaces of the hammer are substantially flat.