Abstract: Disclosed is a Doherty amplifier including a carrier amplifier to perform a signal amplification operation regardless of a level of an input signal, a peaking amplifier to perform an amplification operation, starting from a high power output where a level of an input signal is equal to or greater than a predetermined level, an output combination circuit to combine and output the outputs of the carrier amplifier and the peaking amplifier, and an input division circuit to divide an input signal into the carrier amplifier and the peaking amplifier, the Doherty amplifier including a carrier amplifier output harmonic impedance tuning network installed at a rear end of the carrier amplifier to tune an output harmonic impedance of the carrier amplifier, and a peaking amplifier output harmonic impedance tuning network installed at a rear end of the peaking amplifier to tune an output harmonic impedance of the peaking amplifier.

Abstract: Disclosed is a Doherty amplifier which includes a carrier amplifier for always performing a signal amplification operation regardless of a level of an input signal, a peaking amplifier for performing an amplification operation, starting from a high power output where a level of an input signal is equal to or greater than a predetermined level, an output combination circuit for combining and outputting outputs of the carrier amplifier and the peaking amplifier, and an input division circuit for dividing an input signal into the carrier amplifier and the peaking amplifier, the Doherty amplifier including a carrier amplifier output harmonic impedance tuning network which is installed at a rear end of the carrier amplifier so as to tune an output harmonic impedance of the carrier amplifier, and a peaking amplifier output harmonic impedance tuning network which is installed at a rear end of the peaking amplifier so as to tune an output harmonic impedance of the peaking amplifier.

Abstract: The present invention provides a method of manufacturing a toothbrush with needle-shaped bristles. The method includes the step of setting needle-shaped bristles, partially tapered by being immersed in a chemical, in a head part of a toothbrush body. The method further includes the step of grinding the needle-shape bristles using a drum grinder having protrusions such that end points of the bristles range from 0.01 to 0.03 mm in thickness and tapered portions of the bristles range from 3.5 to 8 mm in length. A toothbrush, in which needle-shaped bristles having end points of 0.03 to 0.05 mm in thickness and tapered portions of 3.5 to 10 mm in length are set, can be manufactured using the method of the present invention. In the present invention, because a manufacturing process is simplified, the required production time and the proportion of defective bristles are markedly reduced.

Abstract: The present invention provides a needle-shaped bristle and a method of manufacturing the needle-shaped bristle. The manufacturing method of the present invention includes the steps of cutting and removing a packing sheet, which is wound around a bundle of bristles, by a length ranging from 30 mm to 50 mm from a first end thereof, and grinding first ends of the bristles using a rotating grinder. The manufacturing method further includes steps of packing the first end of the bundle of bristles, from which the packing sheet is removed, using a packing sheet, cutting the bundle of bristles to a length ranging from 22 mm to 32 mm, and immersing a second end of the cut bundle of bristles, thus tapering second ends of the bristles. The needle-shaped bristle has an advantage of realizing a reduction in the proportion of defective products.

Abstract: A toothbrush tufted with needle-shaped bristles. The bristles are formed of polyester resin. The bristles are 0.1 to 0.2 mm thick before tapering, 13 to 18 mm long, tapered 4 to 8 mm only on one end with a tapered tip thickness of 0.01 to 0.08 mm, and planted to be 7 to 13 mm high in the toothbrush.

Abstract: The present invention provides a method of tapering bristles for toothbrushes and a toothbrush having bristles manufactured using the method. One method disclosed in the present invention includes setting bristles made of polyester in a head insert, and fastening the bristles to the head insert by thermally welding portions of the bristles, protruding from a back surface of the head insert, to the head insert. The method further includes coupling the head insert to a toothbrush body and tapering ends of the bristles by immersing the bristles in a chemical. The bristles can be securely set in the toothbrush body without an anchor. Furthermore, polyester bristles, which could not be set in toothbrushes having variously shaped setting rows due to excessively high stiffness, can be set in these types of toothbrush by the toothbrush manufacturing method of the present invention.

Abstract: The present invention provides a method of manufacturing a toothbrush having needle-shaped bristles and a toothbrush manufactured using the method. The method of the present invention includes the step of grinding bristles, which have been set in a head part of a toothbrush, using a grinder provided with protrusions having heights ranging from 1.5 mm to 7 mm. A toothbrush having needle-shaped bristles can be manufactured without a separate chemical immersion process such that the thicknesses of the end points of the needle-shaped bristles range from 0.01 mm to 0.03 mm and the lengths of the tapered portions thereof range from 3 mm to 9 mm. Time required for production and the defective proportion is markedly reduced, and materials other than polyester can be used as the material for the bristles.

Abstract: Disclosed are a toothbrush and a method of producing the same. The toothbrush of the present invention includes a pressure relief unit installed in a head part of the toothbrush. The unit has a plate shape and a predetermined size sufficient to cover bristles set in the head part. In the present invention, the head part is thin, and the bristles are set in the head part without using a wire. Furthermore, the present invention is easily adapted for mass production using inexpensive equipment. Also, the pressure relief unit serves as a reinforcing unit. Therefore, the head part is prevented from breaking during use despite having a reduced thickness.

Abstract: The present invention provides a method of manufacturing a toothbrush having needle-shaped bristles, and a toothbrush manufactured by the method. The toothbrush manufacturing method of the present invention includes the step of partially tapering ends of bristles, which are made of polyester and are set in a toothbrush body, through a physical grinding process, and the step of completing of a process of tapering the partially tapered bristles by immersing the partially tapered bristles in a chemical. The present invention makes it possible for toothbrush bristles to be tapered through a simple process. Furthermore, the present invention solves conventional difficulties occurring in tapering bristles after setting them in toothbrush bodies.

Abstract: A toothbrush tufted with needle-shaped bristles. The bristles are formed of polyester resin. The bristles are 0.1 to 0.2 mm thick before tapering, 13 to 18 mm long, tapered 4 to 8 mm only on one end with a tapered tip thickness of 0.01 to 0.08 mm, and planted to be 7 to 13 mm high in the toothbrush.

Abstract: A toothbrush tufted with needle-shaped bristles. The bristles are formed of polyester resin. The bristles are 0.1 to 0.2 mm thick before tapering, 13 to 18 mm long, tapered 4 to 8 mm only on one end with a tapered tip thickness of 0.01 to 0.08 mm, and planted to be 7 to 13 mm high in the toothbrush.

Abstract: A toothbrush having needle-shaped bristles with various end points and a method of manufacturing the same. The needle-shaped toothbrush bristle, folded in an asymmetric U-shape to outwardly expose both ends thereof at a height difference ranging from 0.5 to 2 mm and disposed on a head portion of the toothbrush, has a tapered length of 3-7 mm and a blunt end point with a diameter of 0.01-0.07 mm.

Abstract: Disclosed is a toothbrush having soft and hard bristles together. The toothbrush having soft and hard bristles with 6–10 mm in tapered length and 0.01–0.08 mm in diameter of end portions comprises: longer bristles(1) located at both edges; and shorter bristles(2) located at the central portion, wherein the bristles are generally in a semicircular form at their top portions when seen from a side, and a difference in length between the longer bristles(1) and the shorter bristles(2) is about 2–4 mm. The toothbrush can increase brushing efficiency and effectively remove foreign matters between teeth and inside periodontal pockets.

Abstract: A toothbrush tufted with needle-shaped bristles. The bristles are formed of polyester resin. The bristles are 0.1 to 0.2 mm thick before tapering, 13 to 18 mm long, tapered 4 to 8 mm only on one end with a tapered tip thickness of 0.01 to 0.08 mm, and planted to be 7 to 13 mm high in the toothbrush.

Abstract: Disclosed is a toothbrush having soft and hard bristles together. The toothbrush having soft and hard bristles with 6-10 mm in tapered length and 0.01-0.08mm in diameter of end portions comprises: longer bristles(1) located at both edges; and shorter bristles(2) located at the central portion, wherein the bristles are generally in a semicircular form at their top portions when seen from a side, and a difference in length between the longer bristles(1) and the shorter bristles(2) is about 2-4mm. The toothbrush can increase brushing efficiency and effectively remove foreign matters between teeth and inside periodontal pockets.