DE9213313U1 - Guitar, especially bass guitar with solid body - Google Patents

Description

Guitar, especially bass guitar with solid body

The invention relates to a guitar, in particular a bass guitar, with a solid body.

The subject of the invention is the design and structure of electric guitars, which, in contrast to acoustic guitars, are characterized by a solid body.

Three possible designs are known from the current state of the art:

The most common method is to use a solid, homogeneous body made of a single material, which is usually wood, with recesses for the tailpiece, pickups and for attaching the guitar neck. It only extends into the body to a certain depth and is screwed to it. When clamped in, the guitar strings run partly above the neck and in the area of the pickups and tailpiece above the body.
30

This differs from a construction in which the guitar neck runs through the entire body, so that the

Strings are always located above the guitar neck along their entire length. In order to give the guitar body the usual dimensions and satisfactory sound characteristics, half shells are formed on both sides of the guitar neck, which together with the area of the guitar neck located there form the body of the guitar.

In both cases, the surface of the body remains untreated or is painted according to the customer’s wishes.

It is also known that the guitar is made entirely from glass-fiber reinforced plastic material, that is, the guitar neck and body are one piece and made from the same material.

0 Based on this, the invention set itself the task of creating a guitar with a solid body that has excellent sound characteristics.

This object is achieved according to the invention in that an inner core is attached to the body in the direction of the guitar neck and is connected to it, which is surrounded on several sides by hard foam and has an outer skin made of cast material with a wall thickness of 2-5 mm on all sides.

The guitar body proposed according to the invention consists of three different materials.

Inside there is an inner core made of a material of sufficient strength, located in the middle of the body and as an extension of the guitar neck. It is surrounded on several sides by a foam material, with the body in its entirety and on all sides being surrounded by an outer skin made of cast material with a wall thickness of a maximum of 3 mm.

The construction of the guitar body proposed according to the invention is not only equal to the electric guitars known from the state of the art, neglecting production-related fluctuations, but in the case of the production of bass guitars, it is superior in terms of sound.

Firstly, the cast and therefore hard outer skin of the body ensures that the higher frequencies that determine the sound are well absorbed and transmitted. Deep tones, on the other hand, do not lead to the excitation and formation of natural vibrations of the outer skin, so that no energy is taken away from the vibrating string and a largely loss-free vibration occurs.

The foam layer surrounding the inner core serves on the one hand to support the outer skin of the inner core and on the other hand it facilitates the formation of low frequency vibrations and 0 thus the propagation of the particularly low fundamental frequencies that are crucial for bass guitars.

Another advantage is that the

By choosing the casting material and the corresponding additives, any optical effects and color combinations can be created, so that the painting required by the state of the art is completely eliminated and the production process is shortened and thus simplified.

In the following, two methods suitable for producing the body according to the invention for electric guitars, in particular bass guitars, are explained in more detail.

In the first alternative, the wooden core is covered with rigid foam on several sides, preferably on all sides. To produce the outer skin, a mold is coated on the inside with the same material that will later be used for pouring, but which has a higher viscosity due to the addition of appropriate additives. Then, after the core has been inserted, the casting resin is injected. The casting material already coated in the mold combines with the casting material injected to form a unit that can no longer be distinguished from the outside. After hardening, the body is finished.

In an alternative manufacturing variant, the step of filling with rigid foam is simplified and made easier by first producing the inner core and the outer skin, which is located at a distance from it, and then, in the last process step,

an opening in which the foam is introduced into the volume, which is limited on the one hand by the inner core and on the other hand by the outer skin. The decisive advantage is that no additional form is required when applying the layer of rigid foam. Accordingly, production is cheaper and simplified, although increased skill and demands are required in view of the effort required to produce the outer skin.

In principle, the choice of material for producing the outer skin is free within the scope of the invention. In a practical embodiment, the use of epoxy resin with hollow glass microspheres as a reinforcing material is proposed. The latter is essential for producing the necessary mechanical strength. In order to achieve an even distribution of these hollow glass microspheres in the outer skin with regard to the casting process, their adjustable density must be selected so that it corresponds to that of the epoxy resin. This eliminates any segregation effects. This prevents the hollow spheres from sinking or floating upwards during the curing process and giving rise to uneven distribution.

In order to improve the visual effect and create a finish that is ready for sale, additives are added to colour the body or to achieve special optical effects. For example, the addition of metal powder can result in selective reflections of the

create an interesting glitter effect.

Within the scope of the invention, the choice of material for the inner core is basically free. However, it should be chosen so that it has a sufficiently high hardness and strength to ensure a permanently stable connection to the neck of the guitar. It is preferable to make this inner core from wood, although different types of tree lead to audible differences in the sound characteristics.

It is preferable to arrange the inner core within the body in such a way that the outer skin on the side opposite the strings lies directly against the inner core.

In addition, a significant improvement in sound quality can be achieved if an immediate, i.e. direct, connection is established between the inner core and the outer skin at the vibration-transmitting points.

With regard to the foam material, any type of rigid foam, especially polyurethane, is suggested as preferred.

In principle, it is conceivable that both the guitar neck and the body are made in one piece, but this already leads to difficulties in production in terms of dimensions. For this reason, in a further development

The invention proposes to screw the guitar neck onto the inner core, and therefore not to produce a body with a continuous neck.

Further details, features and advantages can be found in the following description, in which an embodiment of the invention is explained in more detail using the drawing. In a schematic representation:

Figure 1 shows a section through the guitar neck in the direction of the central axis.

the body with screwed guitar neck
Figure 2 shows a partially cross-sectional top view of a guitar body according to Figure 1

The inner core (1) runs in the direction of the guitar neck, which is to be mounted later and is therefore only indicated in dotted lines. The same applies to the guitar strings and their holders. On the underside it is directly covered with the outer skin (2) made of a cast material and on the top it is mainly covered with the hard foam layer (3).

The inner core (1) has two recesses for the later mounting of the pickups (4, 5) as well as

in the area of the right front side there is a recess (6) into which the body-side end of the guitar neck will later be inserted and screwed tight.

In order to achieve sufficient stability and load-bearing capacity, the fastening screws penetrate the inner core (1).

In the area of the hard foam layer (3) opposite the recess (6), a recess (7) is provided for later accommodation of the tailpiece.

The result is a body for electric guitars, especially bass guitars, which allows advantageous sound characteristics and interesting optical effects to be realized.

Claims (8)

PATENT ATTORNEY Dipl.-Phys. Dr. W. Pöhner European Patent Attorney ■ European Patent Representative · Mandataire en Brevets Europeens Kaiserstr. 27 · D-8700 Würzburg 1 · Postfach 63 23 · 'S? 09 31 /145 66 · Fax 09 31 /185 66 CLAIMS 1. Guitar, in particular bass guitar with a solid body, characterized in that in the body in the direction of the guitar neck and connected to it an inner core (1) is attached, which is surrounded on several sides by hard foam (3) and has on all sides an outer skin (2) made of cast material with a wall thickness of 2-5 mm. 2. Guitar according to claim 1, characterized in that the outer skin (2) consists of epoxy resin plus reinforcing material, preferably hollow glass microspheres, which have the same density as the epoxy resin. 3. Guitar according to claim 1 or 2, characterized in that the material for the outer skin (2) is provided with additives, for example in the form of coloring and/or metal powder. 4. Guitar according to one of claims 1 to 3, characterized by an inner core (1) made of wood. 5. Guitar according to one of claims 1 to 4, characterized in that on the side opposite the strings the outer skin (2) lies directly on the inner core (1) on the overlying surface. 6. Guitar according to one of claims 1 to 5, characterized in that there is a direct connection between the outer skin (2) and the inner core (1) at the vibration-transmitting points. 7. Guitar according to one of claims 1 to 6, characterized in that the foam (3) is a rigid foam or polyurethane. 8. Guitar according to one of claims 1 to 7, characterized in that the guitar neck is screwed onto the inner core (1).