Aisin Seiki Kabushiki Kaisha

Kabushiki Kaisha Toyoda Jidoshokki Seisakusho

Yoshihiro Naito

Kazuo Noso

Atsuyuki Miura

Koichi Nakayama

Masaru Tsunekawa

Yoshihiro Naruse

Yutaka Momose

Masaya Hyodo

Kazuaki Nakamura

Tatsuya Hayashi

Takanori Hamajima

Hiroya Taniguchi

Noboru Ohtani

Masahiko Hasegawa

Toyoki Furuhashi

Masura Tsunekawa

The present invention provides a multi-stage vacuum pump which includes: a housing in which a plurality of pumping chambers are formed, the pumping chambers being arranged in series and being in fluid communication with one another, one of the pumping chambers which is at one end of the series acting as an initial stage pumping chamber, another of the pumping chamber which is at the other end of the series acting as a final stage pumping chamber, the housing being provided with an inlet port for sucking a gas from a space to be evacuated into the initial stage pumping chamber, the housing being provided with an outlet port for exhausting the gas from the final stage pumping chamber; a Roots-type pump section occupying each of the pumping chambers; and a device for decreasing a temperature differential between the initial stage pumping chamber and the final stage pumping chamber.

Multi-stage vacuum pump

The present invention provides a multi-stage vacuum pump which includes: a housing in which a plurality of pumping chambers are formed, the pumping chambers being arranged in series and being in fluid communication with one another, one of the pumping chambers which is at one end of the series acting as an initial stage pumping chamber, another of the pumping chamber which is at the other end of the series acting as a final stage pumping chamber, the housing being provided with an inlet port for sucking a gas from a space to be evacuated into the initial stage pumping chamber, the housing being provided with an outlet port for exhausting the gas from the final stage pumping chamber; Roots-type pump sections occupying the respective pumping chambers, each of the Roots-type pump sections having a pair of intermeshed Roots-type profile rotors; and a pair of shafts adapted for rotation within the housing about their lengthwise axes in contra-rotational direction, the pair of shafts being secured to the respective Roots-type profile rotors in each of the Roots-type pump sections, one end of each of the shafts being made immovable in its lengthwise direction, the other of each of the shafts being made expandable in its lengthwise direction.

A vacuum pumping apparatus includes a pump housing and a motor housing The housings and are fastened together so as to be a sealed structure by O-rings interposed therebetween. A shaft of a driving device and a driving shaft carrying a rotor are detachably connected via a coupling During operation of the apparatus, a rotor chamber in the pump housing and a motor chamber in the motor housing are equalized in pressure, which requires no mechanical seal therebetween. The coupling facilitates easy removal or detachment of a motor part B from a pump part A, which results in convenient maintenance of the pump part A.

Vacuum pumping apparatus

A multi-stage pump device includes a plurality of pump devices, each of the pump devices having a pump portion feeding working fluid under pressure, and a connecting portion provided between at least two of the pump devices, through which working fluid pumped by the respective pump devices passes. The connecting portion is expandable in a direction of the length thereof and is provided with a sealing structure to prevent a leakage of the working fluid. The connecting portion may be two telescopically arranged pipes or a bellows.

Multi-stage pump device

A multistage vacuum pump assembly comprising plural independent pumping stages connected in series is disclosed. A first pumping stage located at one end of the series is connected to a room to be evacuated, and a final pumping stage located at the other end of the series is connected to the atmosphere. At least the first pumping stage comprises plural pumps connected mutually in parallel, so that the plural pumps together can achieve the vacuum capacity expected without being driven to an excessive rate of rotation.

Multistage vacuum pump assembly

A Stirling engine generating system comprises a Stirling engine driven by solar heat which is used as a heat input source for the engine, a generator driven by the Stirling engine, a temperature sensor detecting the temperature of an operational gas enclosed in an operational space of the engine, an operational gas tank communicated with the operational space via a pair of conduits, one way valves interposed in the corresponding conduits so as to invert the flow direction of the operational gas in each conduit, opening and closing valves each of which is interposed in the respective conduit between the one way valve and the operational gas tank, a field magnet control device for adjusting the rotational speed of the generator and a temperature regulation device for controlling the opening and closing action of the opening and closing valves to vary the operational gas pressure in the operational space in response to a detected signal of the temperature sensor and for controlling the field magnet control device.

Stirling engine generating system

A free piston Stirling engine includes a displacer fitted in a cylinder so as to be able to reciprocate and defining an expansion chamber and a compression chamber in the cylinder, an operational sealing area leading from the expansion chamber to the compression chamber and interposed a heater, a regenerator and a cooler in order, a free piston disposed so as to be able to reciprocate toward a direction which crosses a direction of the reciprocation of the displacer and defining an operational chamber which is communicated with the compression chamber and a buffer chamber at its both ends and a linear generator disposed around the free piston and connected with a storage battery at its output terminal via an AC/DC converter having one or more transformation ratios. According to this constitution, even though the load is larger than the output of the linear generator transitionary, it is possible to supply stable electric power by use of the storage battery. In the opposite direction, it is possible to store the surplus energy in the storage battery when the load is smaller than the output of the linear generator. Accordingly, even though the output of the free piston Stirling engine is under the unbalance condition with regard to the load quantity, especially when the load quantity is larger than the output of the free piston Stirling engine, the free piston Stirling engine can be stably operated.

Free piston Stirling engine

A Stirling engine includes a heater device for collecting solar radiation energy, a heater tube disposed in the heater device and connecting the expansion space and the compression space of cylinder containing a piston, and a transparent partition located in the heater device for defining a closed space. A heat storage material is positioned in the closed space and a temperature detecting apparatus is provided for detecting the temperature of the heat storage material. A pressure regulating arrangement regulates the pressure of a working gas in a working space located between the expansion space and the compression space of the cylinder. A control device controls the pressure regulating arrangement in response to a signal from the temperature detecting apparatus.

Stirling engine

Described is a working gas pressure control apparatus for a Stirling engine including a pressure boost valve provided in a minimum cycle pressure line connected to a working space by a first unidirectional valve, a pressure reducing valve provided in a maximum cycle pressure line connected to the working space by a second unidirectional valve, an operating lever for controlling the opening and closing of the pressure boost and pressure reducing valves, a compressor connected by the pressure reducing and the pressure boost valve to the cycle pressure lines, an unloading valve arranged in a circuit short-circuiting suction and discharge lines of the compressor, and a control unit for opening the unloading valve when engine rpm falls to a value lower than a preset rpm for engine idling, when the pressure boost valve is open and when the engine is operating in the steady state, thereby minimizing compressor load.

Apparatus for controlling working gas pressure in stirling engines

A Stirling engine control apparatus includes a pressure reducing valve provided in a maximum cycle pressure line connecting a working space to a working gas compressor and a working gas tank via a first check valve, a pressure boost valve provided in a minimum cycle pressure line connecting the working space to the working gas storage tank via a second check valve, an operating lever pivotable about a movable fulcrum for controlling opening and closing of the pressure reducing valve and the pressure boost valve, a movable member on which the movable fulcrum of the operating lever is provided, and control means for positionally shifting the movable member upon comparing a target pressure corresponding to displacement of the operating lever and pressure within the minimum cycle pressure line.

Output control apparatus for Stirling engines

An output control system for a Stirling engine includes a pressure reducing valve disposed in a highest-cycle-pressure line and connected between at least one working space and a compressor and a booster valve disposed in a lowest-cycle-pressure line and connected between the working space and the compressor. The pressure reducing valve and the booster valve are selectively actuatable by an accelerator lever attached to a feedback piston cylinder connected to the lowest-cycle-pressure line. The output control system also includes a two-way unidirectional solenoid-operated valve disposed in the highest-cycle-pressure line upstream of the pressure reducing valve and a three-way bidirectional solenoid-operated valve disposed in the lowest-cycle-pressure line downstream of the booster valve. The solenoid-operated valves are controlled by a control unit to close the highest-cycle-pressure line and connect the lowest-cycle-pressure line through a regulator valve to a source of high pressure gas when the engine is at rest.

Growing community of inventors

Nagoya, Japan

Yoshihiro Naito