Chassis for video tape recorder

Claim 2

In a chassis for a video tape recorder comprising a lamellar part for carrying a magnetic tape cassette, a guide drum with magnetic head, a capstan roller and a mechanism for drawing out the magnetic tape from said magnetic tape cassette and loading it around said magnetic head and said capstan roller, said lamellar part having a first hole for installing said guide drum with magnetic head and a second hole for installing said capstan roller, the improvement wherein said chassis is molded integrally with a fiber-reinforced plastic composition and further provided with two guide grooves and/or guide walls encompassing said first hole and designed to guide a sliding movement of said loading mechanism and a reinforcing rib along a boundary between a first region including said guide grooves or guide walls and a second region including said second hole.

Claim 3

A chassis for a video tape recorder according to claim 1, wherein said fiber-reinforced plastic composition comprises one type of resin selected from a group consisting of polycarbonate, polysufone, polyphenylene sulfide and acrylonitrile-styrene copolymer and reinforcing fiber.

Claim 4

A chassis for a video tape recorder according to claim 1, wherein the reinforcing fiber in said fiber-reinforced plastic composition is glass fiber.

Claim 5

A chassis for a video tape recorder according to claim 3, wherein 5% by weight or more of the whole glass fiber component is occupied by those glass fibers which have a length of 1.0 mm or longer and a diameter of 15 μm or less.

Claim 6

A chassis for a video tape recorder according to claim 3, wherein said fiber-reinforced plastic composition contains glass fiber in an amount of at least 10% by weight.

Claim 7

A chassis for a video tape recorder according to claim 1, wherein said fiber-reinforced plastic composition is a composition prepared by blending polycarbonate with glass fibers having a length of 0.5-1.0 mm in an amount of 20-30% of an overall weight of the composition.

Claim 8

A chassis for a video tape recorder according to claim 1, wherein said reinforcing rib is formed by providing said first region at different levels and said second region.

Claim 9

A chassis for a video tape recorder according to claim 1, wherein at least one injection molding gate is provided in a region encompassed by said two guide grooves.

Claim 10

A chassis for a video tape recorder according to claim 7, wherein the region encompassed by said two guide grooves includes a central region including said first hole and a region surrounding said central region, said central region and said surrounding region being demarcated by a difference in level formed such that said central region has a higher level than said surrounding region, said difference in level being smaller than the difference in level between said first region and said second region.

Claim 11

A chassis for a video tape recorder according to claim 1, wherein the radius of curvature at the base of said reinforcing rib is at least 1 mm.

Claim 12

In a chassis for a video tape recorder comprising a lamellar part for carrying a magnetic tape cassette, a guide drum with magnetic head, a capstan roller and a mechanism for drawing out a magnetic tape from said magnetic tape cassette and loading the tape around said magnetic head and said capstan roller, said lamellar part having a first hole for installing said guide drum with magnetic head and a second hole for installing said capstan roller, the improvement wherein injection molding gates are arranged in a cavity of the moding die such that a molten plastic composition flowing in through said respective gates will reach each other substantially equally so that a weld line is formed at a position where leading ends of said respective molten plastic composition flows impinge against each other and a periphery of said cavity as said molten plastic composition, a fiber-reinforced plastic composition, is poured in through said respective gates and solidified, two guide grooves and/or guide walls encompassing said first hole and designed to guide a sliding movement of said loading mechanism, and a reinforcing rib along the boundary between a first region including said guide grooves or guide walls and a second region including said second hole.

Claim 13

In a chassis for a video tape recorder comprising a lamellar part for carrying a magnetic tape cassette, a guide drum with magnetic head, a capstan roller and a mechanism for drawing out a magnetic tape from said magnetic tape cassette and loading the tape around said magnetic head and said capstan roller, said lamellar part having a first hole for installing said guide drum with magnetic head and a second hole for installing said capstan roller, the improvement wherein injection molding gates are arranged in a cavity of the moding die such that a molten plastic composition flowing in through said respective gates will reach each other substantially equally so that a weld line is formed at a position where leading ends of said respective molten plastic composition flows impinge against each other and a periphery of said cavity as said molten plastic composition, a fiber-reinforced plastic composition, is poured in through said respective gates and solidified, two guide grooves and/or guide walls encompassing said first hole and designed to guide a sliding movement of said loading mechanism, and a reinforcing rib along the boundary between a first region including said guide grooves or guide walls and a second region including said second hole.

Claim 14

A chassis for a video tape recorder according to claim 11, wherein four or five gates are provided.

Claim 15

A chassis for a video tape recorder according to claim 11, wherein each said gate is formed by constricting a portion of the gate.

Claim 16

A chassis for a video tape recorder according to claim 11, wherein each gate has a diameter of 1.5-2.5 mm.

Claim 17

In a chassis for a video tape recording comprising a lamellar part for carrying a magnetic tape cassette, a guide drum with magnetic head, a capstan roller and a mechanism for drawing out a magnetic tape from said magnetic tape cassette and loading the tape around said magnetic head and said capstan roller, said lamellar part having a first hole for installing said guide drum with magnetic head and a second hole for installing said capstan roller, the improvement wherein said chassis is molded integrally with a fiber-reinforced plastic composition in which 5% by weight or more of the whole glass fiber component is occupied by glass fibers having a length of over 1.0 mm and a diameter of 15 μm or less, and wherein two guide grooves are provided to guide a sliding movement of said loading mechanism, said guide grooves being covered by a sub-chassis for determining a position of said guide drum with magnetic head and also arranged so as to encompass said first hole, and a first reinforcing rib arranged between one of said guide grooves closer to said capstan roller and a region including said second hole and a second reinforcing rib arranged along most of a periphery of the chassis.

Claim 18

In a chassis for a video tape recording comprising a lamellar part for carrying a magnetic tape cassette, a guide drum with magnetic head, a capstan roller and a mechanism for drawing out a magnetic tape from said magnetic tape cassette and loading the tape around said magnetic head and said capstan roller, said lamellar part having a first hole for installing said guide drum with magnetic head and a second hole for installing said capstan roller, the improvement wherein said chassis is molded integrally with a fiber-reinforced plastic composition in which 5% by weight or more of the whole glass fiber component is occupied by glass fibers having a length of over 1.0 mm and a diameter of 15 μm or less, and wherein two guide grooves are provided to guide a sliding movement of said loading mechanism, said guide grooves being covered by a sub-chassis for determining a position of said guide drum with magnetic head and also arranged so as to encompass said first hole, and a first reinforcing rib arranged between one of said guide grooves closer to said capstan roller and a region including said second hole and a second reinforcing rib arranged along most of a periphery of the chassis.

Claim 19

A chassis for a video tape recording according to claim 1, wherein said first region and said second region are arranged at different levels and said reinforcing rib is formed by a stepped portion between said first and second region.

Claim 20

A chassis for a video tape recording according to claim 16, wherein a second reinforcing rib is provided, said second reinforcing rib being disposed around a substantial portion of an outer periphery of the chassis.

Claim 21

A chassis for a video tape recording according to claim 1, wherein a stepped portion is provided in a central region encompassed by the two guide grooves or guide walls, said stepped portion defines a surface disposed at a level above a surface of the first region and below a surface of the second region.

Claim 22

A chassis for a video tape recording according to claim 1, wherein a stepped portion is provided in a central region encompassed by the two guide grooves or guide walls, said stepped portion defines a surface disposed on a level below a surface of said first region.

Claim 23

A chassis for a video tape recording according to claim 19, wherein said surface defined by said stepped portion is disposed substantially at a same level as a surface of the second region.