Abstract: A circular saw blade to cut electric resistance welded pipes in the electric resistance welded pipe production line experiences an excessive load on hard tips thereof because of the limited cutting time, which results in reduced durability and chipping. [Solution] A flank 18 is provided with a first flank 20 located at the center thereof, and second and third flanks 22, 24 located inclined toward the respective sides of the first flank 20. Therefore, the lateral sides of the flank 18 have a constant clearance angle rearward from a cutting edge 34, which provides advantages of increased strength and resistance to chipping. Furthermore, a fourth flank 26 having a larger clearance angle is separately provided at the rear of the first flank 20 located at the center. Even if the first flank 20 wears, it is possible to reduce the wear on the fourth flank 26 and improve the durability.

Abstract: If input signal is transmitted to a main body unit, a sensor amplifier stores the input signal in itself as measurement data, and transmits the input signal with the added transfer order information to the main body unit. By checking the transfer order information added to the input signal, the main body unit can confirm if the input signal is deficient or not. Upon the end of the measurement of the physical quantity, the main body unit transmits the retransmission request that requests the retransmission of the deficient portion of the data to the sensor amplifier. According to the retransmission request from the main body unit, the sensor amplifier extracts the deficient portion of the input signal data stored in itself and retransmits the extracted input signal data to the main body unit.

Abstract: A circular saw blade to cut electric resistance welded pipes in the electric resistance welded pipe production line experiences an excessive load on hard tips thereof because of the limited cutting time, which results in reduced durability and chipping. [Solution] A flank 18 is provided with a first flank 20 located at the center thereof, and second and third flanks 22, 24 located inclined toward the respective sides of the first flank 20. Therefore, the lateral sides of the flank 18 have a constant clearance angle rearward from a cutting edge 34, which provides advantages of increased strength and resistance to chipping. Furthermore, a fourth flank 26 having a larger clearance angle is separately provided at the rear of the first flank 20 located at the center. Even if the first flank 20 wears, it is possible to reduce the wear on the fourth flank 26 and improve the durability.

Abstract: [OBJECT] To make tips less likely to be damaged. [MEANS OF REALIZING THE OBJECT] A tip (30) has a first rake face (40) that is contiguous with a cutting edge (32), and a second rake face (42) that is contiguous with the first rake face and faces a gullet (16) provided in front of the tip (30) in the rotational direction, wherein the second rake face (42) has a radially inward inner edge that is in contact with the outer peripheral edge of the base metal (12) that defines the gullet (16). The second rake face (42) is formed such that the second rake angle (02), which is formed between a first reference line (L1) drawn from the rotation center of the circular saw blade to the cutting edge (32) and a second reference line (L2) that passes through the radially inward inner edge along the second rake face (42), is a negative angle.

Abstract: If input signal is transmitted to a main body unit, a sensor amplifier stores the input signal in itself as measurement data, and transmits the input signal with the added transfer order information to the main body unit. By checking the transfer order information added to the input signal, the main body unit can confirm if the input signal is deficient or not. Upon the end of the measurement of the physical quantity, the main body unit transmits the retransmission request that requests the retransmission of the deficient portion of the data to the sensor amplifier. According to the retransmission request from the main body unit, the sensor amplifier extracts the deficient portion of the input signal data stored in itself and retransmits the extracted input signal data to the main body unit.

Abstract: A disc-shaped tool includes a plurality of virtual regions formed such that it is surrounded by two radius lines extending from a rotation center of a disc-shaped base metal and two concentric circles on the base metal disposed around the rotation center. A central angle formed by the two radius lines is equal to or less than 90°, and the number of the virtual regions is 4 to 24. The concentric circle located in a center of an interval of the two concentric circles forming the virtual region is in a range of 0.6 r to 0.8 r with respect to the rotation center of the base metal when a maximum gullet bottom radius of the base metal is r. An overlapping of the virtual regions continuously adjoining each other is in a range of 0° to 12°. A minimum neighborhood distance between the adjoining slits is equal to or more than 0.05 r. A ratio of a length of an arc of the central concentric circle in each virtual region with respect to the interval of the two concentric circles in the virtual region is 3 to 6.

Abstract: A particle counter for measuring the number of floating particles contained in a sample to determine the particle concentration therein includes: a memory section for storing a relational expression between the direct current level output from a photoelectric converter when no particles exist and the frequency of occurrence of false counts; and a subtraction section for determining the frequency of occurrence of the false counts corresponding to the direct current level output from the photoelectric converter at the time of commencement of measurement with reference to the relational expression stored in the memory section and subtracting a value based on the frequency of occurrence of the false counts from a discrete value after commencement of measurement.

Abstract: A particle counter for measuring the number of floating particles contained in a sample to determine the particle concentration therein includes: a memory section for storing a relational expression between the direct current level output from a photoelectric converter when no particles exist and the frequency of occurrence of false counts; and a subtraction section for determining the frequency of occurrence of the false counts corresponding to the direct current level output from the photoelectric converter at the time of commencement of measurement with reference to the relational expression stored in the memory section and subtracting a value based on the frequency of occurrence of the false counts from a discrete value after commencement of measurement.

Abstract: A particle counter for measuring the number of floating particles contained in a sample to determine the particle concentration therein comprises: a memory section 11 for storing a discrete value C per unit of time based on the maximum particle number concentration set in the specification in advance; an operation processing section 12 for comparing a discrete value M per unit of time to be actually counted to the discrete value C per unit of time stored in the memory section 11; and an output section 4 for outputting the information based on the comparison results of the operation processing section 12.

Abstract: A disc-shaped tool 10 includes a plurality of virtual regions formed such that it is surrounded by two radius lines extending from a rotation center of a disc-shaped base metal 11 and two concentric circles on the base metal disposed around the rotation center. A central angle formed by the two radius lines is equal to or less than 90°, and the number of the virtual regions is 4 to 24. The concentric circle located in a center of an interval of the two concentric circles forming the virtual region is in a range of 0.6 r to 0.8 r with respect to the rotation center of the base metal when a maximum gullet bottom radius of the base metal is r. An overlapping of the virtual regions continuously adjoining each other is in a range of 0° to 12°. A minimum neighborhood distance between the adjoining slits is equal to or more than 0.05 r. A ratio of a length of an arc of the central concentric circle in each virtual region with respect to the interval of the two concentric circles in the virtual region is 3 to 6.

Abstract: To eliminate a drawback of the prior art that reduction of the thickness of a circular saw lowers the critical rotational speed of the circular saw, making the buckling phenomenon more likely to occur, there are provided a construction of a circular saw which makes it possible to prevent the critical rotational speed of the circular saw from being lowered due to reduction of the thickness of the circular saw, and increase the critical rotational speed to twice the speed of a conventional circular saw, and a method of fixing the same to a main rotary spindle. More than two slits are formed in a body formed with a central hole, such that the more than two slits extend directly from the central hole or from the vicinity of the central hole, at predetermined intervals of angles about a center of the circular saw, and terminate at respective locations within an annular range set to 60% to 75% of the tooth bottom radius of the circular saw.

Abstract: A carriage conveying apparatus has a loaded carriage to be conveyed, and a driving vehicle for coupling, towing and conveying the carriage from below the carriage. Since the vertical load of the carriage is transmitted to the driving vehicle, controlled to a proper magnitude, the driving vehicle may be reduced in size and weight, and it is also possible to have stable travel if the carriage is empty. By designing all three wheels so as to be driven and steered, sideways and spin-turn motions are realized. By providing recognition marks and detecting means, it is possible to position the driving vehicle accurately if the setting position of the carriage deviates.

Abstract: A cartridge to be inserted into a drive unit includes a casing containing a recording medium disc to be driven by the drive unit. The disc has a hub fixed at its center. Center windows are provided at opposite sides of the casing and allow the hub to be inserted therethrough. Head windows are provided also at opposite sides of the casing and allow a reading head to access information recorded on opposite sides of the disc. Shutters are provided around the center windows and normally cover the head windows. These shutters are rotatable about the center windows and uncover the head windows when the cartridge is inserted into the drive unit. An actuator for rotating the shutters is provided between the shutters and the outside of the casing. The actuator has a portion exposed to the outside of the casing so that the shutters are automatically and indirectly rotated by an external force applied to the actuator when the cartridge is inserted into the drive unit.

Abstract: A photographic apparatus for producing a visible image on a photosensitive nit including a photosensitive film mounted on a film mount. The apparatus includes: a first member having a supplying station, an exposure station, a developing station and a fixing station provided on a principal surface thereof; two transfer means, one for transferring the unit from the supplying station to the exposure station and or for transferring the unit from the exposure station to the developing station, and from the developing station to the fixing station; and driving means for driving the two transfer means. A latent image of an original is formed on the film at the exposure station, the latent image is developed at the developing station, and the developed image is fixed at the fixing station.