JPH0412090B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a molded article of a fishing line weight and a method for manufacturing the weight.

[Prior art]

Small weights are generally formed by sintering and machining metals such as tungsten and its alloys, which are used in balance weights and the like.
Because these weights are expensive, more traditional cast lead is used for many applications, such as fishing line weights. This material (lead) can be squeezed and deformed to grip a fishing line. In the prior art, methods for manufacturing fishing weights by adding lead powder to hardenable or moldable materials include a method for manufacturing molded weights with fishing line tied to the outside (U.S. Pat. No. 3,192,662); ), a method of forming foldable blocks along fishing line (U.S. patent
3638347 and British Patent Specification 2048631A), and a method of forming along a tubular core member (U.S. Pat.
3782025).

There are a number of disadvantages to using lead. That is, there is now a strong interest in the toxic effects of lead on wild areas such as fishing areas. In addition, lead weights, especially small ones, are difficult to handle and are inconvenient to fix to or remove from the fishing line. This is because the material must be deformed to tighten it onto the fishing line. In the case of the weights described in US Pat. No. 3,192,662, attaching the weights to the yarn requires a high degree of dexterity, and each weight is only suitable for a narrow range of yarn thicknesses.
A bendable weight easily loosens or comes off when it hits an underwater obstacle or when force is applied to the weight during insertion.

It has also been proposed to fabricate fishing weights with permanganate weights within the outer jacket layer (US Pat. No. 3,852,907). Since this type of weight does not grip the fishing line, it can only be used as a sinking weight, but the specification of the above-mentioned patent states that the weight can be made by providing pointed irregularities on the outer jacket layer of lead and caulking it to the fishing line. It is stated that it can be fixed to a fishing line. In this case, most of the weight is made of permanganite, but since lead is used in the outer jacket layer, there are almost the same toxicity problems as if the weight were made entirely of lead. Furthermore, this type of sinker requires a considerable amount of force to securely tighten onto the fishing line, and the entire weight is easily deformed, so it cannot be reused.

[Summary of the invention]

The present invention provides a weight formed from a mass of metal particles embedded in a matrix of curable, e.g. polymeric material, which curable material together with the metal particles forms a stable shape composite material. The weight is comprised of a plurality of body parts connected to each other by flexible hinge means, which can be closed together to lock the weight to a fishing line or wire-like member. It's becoming like that. Here, the term "metal" shall mean not only the original metal but also its alloys.

The matrix material constitutes substantially less than 20% of the total weight, preferably less than 10%, and in the case of maximum weight density, less than 5%.

In one embodiment of the invention, the hinge means comprises a flexible member fixed to and connecting the body parts. In this embodiment, the body portions are similarly engaged and pressed together, but the hinge means is made of a highly malleable material to ensure that the hinge means holds the body portions together when the body portions are closed. They can be pressed together and used many times. Preferably, in this case, the hinge means is a strip or wire of uniform or non-uniform cross-section made of copper or other malleable metals or alloys thereof.

A preferred method of manufacturing weights of the latter embodiment is to use two cooperating molds with a series of molding cavities arranged along at least one row, and before closing the molds. A hinge strip or wire is placed between the two molds and extends through the cavities of said row, with separating means in the cavities so that a hinge strip or wire is placed in each cavity on one side of the strip or wire in the cavity. The protrusion allows the gap between the body parts to be located on one side of the hinge means when molding material is injected into the cavity and the body parts are molded. The molded cavities are then arranged in a grid, the strips or wires of the hinge means extend in one direction through the rows of cavities, and the bar-shaped separation means extend the rows of cavities transversely to said direction. pass through and extend it.

In another embodiment of the invention, the hinge is arranged to act as a spring, communicating the spring body parts with each other and bringing them into close contact with each other by means of a compressive force, so that the weight is held on the fishing line by.

Non-limiting examples of suitable high-density composite materials that can be used in weights produced according to the present invention are as follows.

Example 1 Pre-pressed and crushed tungsten powder is sifted through a 100-mesh sieve to remove fine particles, and then mixed with a paddle mixer to form a silicone rubber (e.g., commercially available from ICI PLC in the UK under the trademark Silcoset 152). 97.1% by weight of powder and 2.9% by weight of silicone rubber. The mixture can be molded by injection molding or extrusion, resulting in an elastic material with a density of 10.6 g/cm ^{3 ,} which is close to that of lead.

Example 2 In the method of Example 1 above, 3.8% by weight of silicone rubber was added to 96.2% by weight of tungsten powder, resulting in a material with a density of 9.6 g/cm ³ .

Example 3 In the method of Example 1, 7.2% by weight of silicone rubber was added to 92.8% by weight of tungsten powder, resulting in a material with a density of 8.8 g/cm ³ .

Example 4 The tungsten powder or tungsten alloy powder prepared by the method of Example 1 was mixed with low-density polyethylene (for example, manufactured by DuPont, Canada under the trade name
8503GUB1) and metal powder 96
% by weight and 4% by weight of polyethylene. The mixture was ground in a ball mill, then charged into the filling chamber of an extruder, heated to 260°C, and extruded through a nozzle. The extruded material was cooled and crushed into small pieces, yielding a material suitable as a feedstock for injection molding processes. The density of the material was 9.6 g/cm ² .

It is also possible to use other hardenable materials, especially polymeric materials, as a matrix for the metal powder if a suitably stable shape can be obtained, and metals other than tungsten can be used if a sufficiently high specific gravity can be obtained. You can also do that. Generally, a satisfactory product will not require more than approximately 2.5% by weight of matrix material, the upper limit being set only by the minimum acceptable density of the final material.

The matrix/metal composite used in the present invention may also be prepared using a two-part polymer/curing agent matrix material as the matrix. In this case, the metal powder can be mixed with part of the matrix material and then the remaining part added.

〔Example〕

Embodiments of the present invention will be described below with reference to the accompanying drawings.

1 to 4, the fishing weight 2 consists of two hemispherical parts 4a and 4b,
These parts are connected to each other by a thin integral strip 6. One hemispherical part is provided with a constricted projection 8 in the center, and the other hemispherical part is provided with a recess 10 that fits into said projection.
A slot 12 extends across the inner surface and projection of the first hemispherical portion 4a and is adapted to allow passage of a fishing line therethrough. This weight is molded from materials such as those described in Examples 1 to 3 above. Therefore, the strip connecting the two hemispherical parts has considerable flexibility, which makes the 2
The two parts can be easily folded. A central protrusion 8 and a recess 10 that fits therein.
The peripheral wall of the fishing rod also has a similar elasticity, so that the two hemispherical parts can easily be snapped together to securely fix the sinker to the fishing line. In this way, the weight can be repeatedly slid to a desired position and held there by friction. When the weight is removed, the two hemispherical parts can be opened again just as easily without damaging the weight or the fishing line.

As shown in FIG. 4, it is possible to use a mold that can simultaneously mold a series of weights in a single injection stroke, thereby reducing manufacturing costs.

Depending on the material of the matrix, a low temperature curing molding method may be used, or curing may be accelerated by heat.

FIG. 5 shows a weight 22 according to a second embodiment, which likewise consists of two substantially hemispherical body portions 24a, 24b, which form a narrow intermediate portion 24c. Therefore, they are joined to each other. A wedge-shaped gap 25 of approximately 12 DEG is formed on the central hinge surface across most of the diametrical area of the weight. A copper wire 26 having a diameter of about 0.4 mm extends through both main body portions across the intermediate portion 24c.
It constitutes a hinge between both body parts.

When the fishing line is inserted into the gap 25 and the body parts are pressed together, the copper wire acts as a hinge shaft to close the body parts onto the fishing line. Since flexible copper wire is used as the hinge, the molded material forming the body portion may be relatively inelastic, and in some cases, when the copper wire is flexed, the middle of the central hinge surface area The portion 24c may be so fragile that it can be torn. The fishing line is reliably gripped because the copper wire is plastically deformed by the flexible strain acting on the minute exposed portion of the copper wire. Due to the high malleability of copper, the hinge can be opened and closed many times, so the weight can be reused. Needless to say, if the material of the body portion exhibits elasticity, it is possible to provide a connecting member as in the embodiments of FIGS. 1 to 3.

The weight shown in FIG. 5 was manufactured by the method shown in FIGS. 6 and 7, and an injection molding machine is used to simultaneously manufacture a large number of weights. The upper mold 40 and the lower mold 42 have substantially hemispherical depressions 4 corresponding to each other.
4 are provided along the rows of a rectangular grid. Along one directional row, a series of separation blades 46 are provided in the center of the lower mold recesses. These blades have a wedge-shaped cross section, the apex of which is located approximately 3/4 of the height of the mold cavity.

The upper surface of the lower mold is provided with a shallow groove 48 at right angles to the blade, intersecting the row of depressions at the center of the depression. A copper wire 28 drawn out from a spool (not shown) is passed through these grooves and stretched over the upper surface of the lower die 42 via a guide 50. A notch 52 is provided in the blade.
These notches 52 accommodate the copper wire at the intersection of the copper wire and the blade, so that the blade protrudes above the copper wire into the gap between the copper wires.

The upper die 40 has an outlet nozzle 54 from the filling chamber 56.
is provided, and the upper mold 40 is attached to a heating jacket 58 surrounding the filling chamber. The molding material charged into the filling chamber is prepared in the form of pellets in which metal powder is mixed in a plastic matrix, and a suitable material is the material of Example 4 above. The molding material is kept under pressure in the filling chamber at 260 °C
℃ and is forced into the mold cavity in a fluid state by a ram 60 fitted with a filling plunger 62. The pressure of the incoming molding material causes the copper wire to be stretched into an arcuate shape as shown in FIG. 5, so that the hinge is securely retained in the mass of material forming the body portion.

Once the mold is opened, the weight can be taken out as a single bead-shaped molded body. In this molded body, each weight has a copper wire extending in one direction and
They are connected to each other by a burr of molding material extending in a 90° direction. Each weight can be separated if necessary.

Referring again to Figure 5, it should be noted that
Since the apex of the blade protrudes above the copper wire hinge to approximately 3/4 of the height of the weight, at the central hinge plane the molding material is applied to the small area above the copper wire in Figure 5. It only occupies space. Therefore, when both body parts are closed to the fishing line by finger pressure, a tensile force is exerted on the part of the molding material on the central hinge surface. Since the molding material has a high powder content and the matrix material is inelastic, the tensile forces easily tear the molding material section apart, leaving the copper wire as the only effective hinge member. The unrestrained copper wire embedded in the molding material is of minimal length and therefore the bending of the hinge is localized to a small area, resulting in plastic deformation and thus the insertion into the wedge-shaped gap. The fishing line is securely gripped. but,
Due to the high malleability of copper, the hinge can be opened and closed many times, allowing the weight to be used repeatedly.

The weight of FIG. 8 was manufactured by the method of FIGS. 9 and 10 using equipment similar to that of FIGS. 6 and 7, but in this example a strip or wire 28 is made of a spring material with a uniform or non-uniform cross-sectional shape as shown in FIG.
It includes a plurality of corrugated portions 63 spaced apart from each other. In this case, since the spring material is pre-tensioned prior to molding, each corrugated portion acts as a spring 66 as soon as manufacturing is completed, and
The two faces 64 of the weight are drawn together by the spring and press against each other. The blade is shaped so that when the surfaces 64 abut one another, a groove or blunt portion 65 is formed at the outer edge of the slot. This blunt portion allows the weight to be force-fitted onto a fishing line or other wire, and the stability of the weight's position is maintained by the frictional force created by the compressive load of the spring 66. Such self-gripping weights can be reused many times.

In any of the embodiments described above, the opposing surface (64 in FIG. 8) of the body portion can be roughened, such as by molded ridges or other lines, to provide a more secure grip on the fishing line.

[Brief explanation of drawings]

FIG. 1 is a front view of the first embodiment of the molded weight, FIG. 2 is a side view of the weight in a slightly folded state, and FIG. 3 is a side view of the weight in a completely folded state.
Fig. 4 shows an example of a method for producing a series of weights as injection molded products, Fig. 5 is a sectional view of another embodiment of the weight, and Figs. 6 and 7 show the weights in Fig. 5. FIG. 8 is a sectional view of another embodiment of the weight, and FIGS. 9 and 10 are illustrations of the manufacturing method of the weight shown in FIG. 8. 4a, 4b, 24a, 24b... Weight main body portion, 6, 26, 66... Hinge means, 8, 10...
...Connection part, 28...copper wire or strip material.

Claims (1)

Claims: 1. At least two body portions connected by flexible hinge means and closed together to engage a fishing line by bending the flexible hinge means, the body portions having: each having a mass of metal particles embedded in a matrix of hardenable material, said flexible hinge means being formed from a strip or wire (26 or 66) of a non-hazardous metal or alloy; Each end of the strip or wire is connected to the respective body portion 24.
A fishing weight, characterized in that it is molded into the inside of the parts a and 24b. 2. The fishing sinker according to claim 1, wherein the ends of the strips or wires 26, 66 molded into the body parts 24a, 24b are of non-linear configuration. the law of nature. 3. The fishing weight according to claim 1 or 2, wherein the main body portion is made of tungsten or tungsten alloy powder. 4. The fishing weight according to claim 3, wherein the matrix material is silicone rubber or polyethylene. 5. The fishing weight according to any one of claims 1 to 4, wherein the strip material or wire material is made of a ductile metal. 6. The fishing weight according to claim 5, wherein the strip material or wire material is made of copper. 7. Claim 1, characterized in that the strip material or wire material is made of a material to which stress has been applied in advance.
The fishing weight described in any one of paragraphs to paragraphs 4 to 4. 8. A plurality of body portions 24a, 2, each weight formed of a material consisting of a block of metal particles embedded in a matrix of curable polymeric material.
4b, said body parts being connected to each other by flexible hinge means (6, 26 or 66), said fishing line or striations being made by bending said flexible hinge means and closing the body parts together. For manufacturing a plurality of weights adapted to be attached to a shaped member, two molds 40, 42 are provided with a series of mold cavities 44 arranged along at least one row.
and a flexible strip or wire 28 of non-toxic metal or alloy for forming the hinge means (26 or 66) is placed between the two molds to close the cavities of the row. a separating means 46 is provided in said cavity and projects into each cavity on one side of the strip or wire in said cavity, and molding material is injected into said cavity to mold said body part. A method for manufacturing a weight, characterized in that the gap between the body parts is located on one side of the hinge means. 9 The separating means provided in each cavity consists of a member in the form of a blade or bar 46 with a wall thickness tapering towards the flexible strip 28, so that during molding the strip is 9. The method of manufacturing a weight according to claim 8, wherein the weight is brought into contact with a 46. 10. The method for manufacturing a weight according to claim 8 or 9, wherein the strip material is accommodated in a notch 52 of the blade. 11 The portion of the band material constituting the hinge means (26 or 66) that is embedded in the main body portion is
The method for manufacturing a weight according to any one of claims 8 to 10, characterized in that the weight has a non-linear shape. 12 The strip is held under tension in the cavity row and has a plurality of corrugations 63, one corrugation located at each blade 46.
is provided, and when the weight molded body is removed from the mold and the blade, the corrugated portion to which stress has been applied in advance forms a spring 66, so that the mutually connected main body portions are brought into pressure contact with each other. A method for manufacturing a weight according to any one of claims 8 to 11, characterized in that: 13 The molded cavities 44 are arranged in a grid and the strips or wires 28 constituting the hinge means extend in one direction through parallel rows of cavities and the separating means in the form of blades or bars 46 13. A method as claimed in claim 12, characterized in that the weights are extended through parallel rows of cavities transversely to the direction.