Abstract: A brushcutter includes: a centrifugal clutch (20) that transmits a drive force of an engine from a crankshaft to a drive shaft; a clutch housing (23) covering the cooling fan and the centrifugal clutch, the clutch housing being made of a synthetic resin; and a bearing that is held inside the clutch housing (23) and supports a coupling shaft that couples the drive shaft and the centrifugal clutch (20). A volute-shaped air-flow space (27) defined including a rise wall (26) surrounding the centrifugal clutch (20) is provided inside the clutch housing (23) near an outer circumference of the centrifugal clutch (20). An inflow opening (28, 29) that lets a cooling air flowing in the air-flow space (27) flow into an inner air-flow space (53) and an outflow opening (52) that lets the cooling air flowing in the air-flow space (53) flow out to the air-flow space (27) are provided on the rise wall (26).

Abstract: A brushcutter includes: a centrifugal clutch (20) that transmits a drive force of an engine from a crankshaft to a drive shaft; a clutch housing (23) covering the cooling fan and the centrifugal clutch, the clutch housing being made of a synthetic resin; and a bearing that is held inside the clutch housing (23) and supports a coupling shaft that couples the drive shaft and the centrifugal clutch (20). A volute-shaped air-flow space (27) defined including a rise wall (26) surrounding the centrifugal clutch (20) is provided inside the clutch housing (23) near an outer circumference of the centrifugal clutch (20). An inflow opening (28, 29) that lets a cooling air flowing in the air-flow space (27) flow into an inner air-flow space (53) and an outflow opening (52) that lets the cooling air flowing in the air-flow space (53) flow out to the air-flow space (27) are provided on the rise wall (26).

Abstract: This invention provides a battery pack for driving a compact electric motor of a compact engine starting device mounted on a working machine, comprising lithium-based secondary battery comprising two cells, the entire discharge capacity of the cells being 500 to 2000 mAh, charging voltage per one cell being 3.0 to 4.2 V, various electronic circuits like driving and battery protection circuits of an electric motor, maximum discharge current of the battery having high rate of 10 to 60 A, the protection circuit including an overdischarge inhibit circuit (A) interposed in the electric motor driving circuit and automatically stopping the driving operation of the electric motor after time required for starting the engine elapsed, the volume of the battery pack being as extremely low as 2.5×104 to 1.0×105 mm3, the tire required until the engine is started from the actuation of the electric motor being set to an interval as short as 5 to 15 seconds, since high current can flow.

Abstract: An operation unit is provided with an engine operation box storing a control operation portion controlling an opening degree of a throttle valve and a start switch terminal connected to a start motor; a throttle operating lever for controlling the opening degree from an idle position to a full-open position; and a start switch connecting and disconnecting the start switch terminal, wherein the throttle operating lever has a switch shielding portion which enables to operate the start switch without an interference between the throttle operating lever and an operating portion of the start switch when the throttle operating lever is at an idle position, and disables to operate the start switch by shielding at least a part of the operating portion of the start switch by means of a part of the throttle operating lever when the throttle operating lever is operated to be apart from the idle position.

Abstract: This invention provides a battery pack for driving a compact electric motor of a compact engine starting device mounted on a working machine, comprising lithium-based secondary battery comprising two cells, the entire discharge capacity of the cells being 500 to 2000 mAh, charging voltage per one cell being 3.0 to 4.2 V, various electronic circuits like driving and battery protection circuits of an electric motor, maximum discharge current of the battery having high rate of 10 to 60 A, the protection circuit including an overdischarge inhibit circuit (A) interposed in the electric motor driving circuit and automatically stopping the driving operation of the electric motor after time required for starting the engine elapsed, the volume of the battery pack being as extremely low as 2.5×104 to 1.0×105 mm3, the tire required until the engine is started from the actuation of the electric motor being set to an interval as short as 5 to 15 seconds, since high current can flow.

Abstract: An operation unit is provided with an engine operation box storing a control operation portion controlling an opening degree of a throttle valve and a start switch terminal connected to a start motor; a throttle operating lever for controlling the opening degree from an idle position to a full-open position; and a start switch connecting and disconnecting the start switch terminal, wherein the throttle operating lever has a switch shielding portion which enables to operate the start switch without an interference between the throttle operating lever and an operating portion of the start switch when the throttle operating lever is at an idle position, and disables to operate the start switch by shielding at least a part of the operating portion of the start switch by means of a part of the throttle operating lever when the throttle operating lever is operated to be apart from the idle position.

Abstract: Succinic acid compounds of the formula: ##STR1## wherein A represents a heterocyclic group, a 3 to 8-membered cycloalkyl group or a phenyl group which may have one or more substituents selected from the group of a halogen atom, a lower alkyl group having 1 to 6 carbon atoms and a lower alkoxy group having 1 to 6 carbon atoms; B represents a bicyclic amino group which may have 1 or 2 unsaturated bonds, with the proviso that B bonds to the carbon atom of the carbonyl group at the nitrogen atom; R represents a hydrogen atom or combines each other to form a chemical bond; R.sup.

Abstract: As new compound is provided a cyclohexane derivative of the formula ##STR1## wherein R.sup.1 is a hydrogen or a lower alkyl; R.sup.2 is a lower alkyl; R.sup.3 is a hydrogen, an alkyl, an alkenyl, a hydroxyalkyl, a cycloalkyl, a morpholino, an aminoalkyl, an N-alkylaminoalkyl, an N,N-di-alkylaminoalkyl, an alkoxycarbonylalkyl, a group of the formula --(CH.sub.2).sub.l --R.sup.4 where R.sup.4 is a lower alkoxy, a lower alkylthio, a benzylthio, an anilino, a morpholino, a piperazino, a piperidino or a lower alkyl-substituted piperidino and l is 2 or 3, a group of the formula ##STR2## where X is a halogen, a lower alkyl, a lower alkoxy, a phenoxy or an alkoxycarbonylalkyloxy, m is zero or 1 and n is an integer of zero to 2, inclusive, a group of the formula --CH.sub.2 --R.sup.5 where R.sup.5 is a furyl, a thenyl or a pyridyl, or a group of the formula ##STR3## where R.sup.5 is as defined above; or a salt of said cyclohexane derivative.

Abstract: A new compound is provided by a cyclohexane derivative of the formula ##STR1## wherein R represents a hydrogen atom or an alkyl group, an alkylthioalkyl group or an unsubstituted or substituted phenyl group; and R.sup.1 represents an alkyl group, an unsubstituted or substituted benzyl group, a phenethyl group, a phenoxymethyl group, a 2-thienylmethyl group, an alkoxymethyl group or an alkylthiomethyl group, or a salt of said cyclohexane compound.This cyclohexane compound exhibits useful plant-growth regulating effects on crop-plants and also non-crop plants such as lawn and may be prepared by cyclization of an acetonylsuccinic acid dialkyl ester, followed by reaction with an organic acid chloride and by intermolecular rearrangement.

Abstract: As new compound is provided a cyclohexane derivative of the formula ##STR1## wherein R represents a hydrogen atom or an alkyl group, an alkylthioalkyl group or an unsubstituted or substituted phenyl group; and R.sup.1 represents an alkyl group, an unsubstituted or substituted benzyl group, a phenethyl group, a phenoxymethyl group, a 2-thienylmethyl group, an alkoxymethyl group or an alkylthiomethyl group, or a salt of said cyclohexane compound.This cyclohexane compound exhibits useful plant-growth regulating effects on crop-plants and also non-crop plants such as lawn and may be prepared by cyclization of an acetonylsuccinic acid dialkyl ester, followed by reaction with an organic acid chloride and by intermolecular rearrangement.

Abstract: As new compound is provided a cyclohexane derivative of the formula ##STR1## wherein R represents a hydrogen atom or an alkyl group, an alkylthioalkyl group or an unsubstituted or substituted phenyl group; and R.sup.1 represents an alkyl group, an unsubstituted or substituted benzyl group, a phenethyl group, a phenoxymethyl group, a 2-thienylmethyl group, an alkoxymethyl group or an alkylthiomethyl group, or a salt of said cyclohexane compound.This cyclohexane compound exhibits useful plant-growth regulating effects on crop-plants and also non-crop plants such as lawn and may be prepared by cyclization of an acetonylsuccinic acid dialkyl ester, followed by reaction with an organic acid chloride and by intermolecular rearrangement.

Abstract: A method for protecting one or more metallic materials of equipment auxiliary to a fluidized incinerator from corrosion, said fluidized incinerator being adapted to cause waste materials including a chlorine-containing compound to burn to ashes and said metallic materials being exposed to a combustion gas and heated to a temperature of at least 450.degree. C. at their surfaces, which method comprises causing an alkali metal or alkaline earth metal carbonate to be present in the ashes at a rate of 0.3-5 equivalents based on all the chlorine contained in the ashes present in the equipment.

Abstract: In a process for separating a conjugated diene from a hydrocarbon mixture containing the conjugated diene by extractive distillation using dimethyl formamide as an extractive solvent, a method for inhibiting polymerization of the conjugated diene in the dimethyl formamide at a high temperature which comprises using furfural and furfural polycondensates as polymerization inhibitors, and controlling the amounts of the polymerization inhibitors such that about 0.01 to about 2% by weight, based on the solvent, of furfural and about 0.5 to about 10% by weight, based on the solvent, of the furfural polycondensates are present in a total amount of about 1 to about 12% by weight, based on the solvent, throughout the entire separating process.