Classes IPC  ?

• A01M 1/02 - Systèmes fixes pour capturer ou détruire les insectes avec dispositifs pour attirer les insectes

Abrégé

Disclosed is a servo valve comprising a valving element that rotates between different operating positions in order to connect to valve ports by means of grooves in the valving element. the grooves are formed symmetrically in both sides of the valving element, each pair of symmetrical grooves being optionally separated by a stiffening web having holes to allow fluid to flow between the grooves. Control ports are formed between certain edges of the grooves in the valving element and the edges of corresponding grooves in fixed elements adjacent to the valving element and specially designed for this purpose. Flow paths inside the valve are formed by the grooves in the valving element and in the adjacent fixed elements, providing a sufficient flow area. The surface area of each control port is increased by adding a pair of symmetrical holes in both sides of the valving element, thus doubling the control surface area and balancing the components of lateral flow force. Each portion of the valving element is subjected to the same pressure, which provides static balance. The rotary movement provides the control ports with relatively large surface areas with respect to short-stroke rotary or linear actuators. Furthermore, the thin, grooved valving element provides minimum inertia for a high-speed response.

Classes IPC  ?

• F16K 11/00 - Soupapes ou clapets à voies multiples, p. ex. clapets mélangeursRaccords de tuyauteries comportant de tels clapets ou soupapesAménagement d'obturateurs et de voies d'écoulement spécialement conçu pour mélanger les fluides
• F16K 39/00 - Dispositifs pour relâcher la pression sur les faces d'un joint d'étanchéité
• F15B 13/04 - Dispositifs de distribution ou d'alimentation du fluide caractérisés par leur adaptation à la commande de servomoteurs pour utilisation avec un servomoteur unique

Abrégé

Disclosed is a valve that works by means of a poppet or spool that covers a port in a first position and then switches to cover a second opposite port in a second position. In each of the two positions, the poppet or spool separates the covered port from a third port and connects the third port to the second port, reversing the connection in the second position. To ensure a fast response, the poppet or spool has minimal mass, and consequently minimal inertia, and switches between the two positions over a short distance under the effect of an actuator, returning under the effect of a spring, a liquid (or gas, in the case of other applications) under high pressure and which can provide a large drive force, or both together. The high pressure acts on two adjacent surface areas on both sides of the poppet or spool, providing two important features: firstly, the actuator needs to provide enough force to counter the force resulting from the effect of the high pressure on the difference of the two surface areas only, and not on the large lateral surface area of the poppet; and secondly, the thickness of the poppet disc can be significantly reduced, greatly reducing the mass thereof, and consequently the inertia of same. In particular cases, two ports can be used instead of three, and the two ports can be connected to the third port by means of high pressure that is used as control pressure during the rapid return of the poppet. A permanent separation or connection can also be created between any two lines in either operating position. The valve can be used with compressed air in pneumatic control, using suitable production materials, as well as in hydraulic control.

Classes IPC  ?

• F16K 11/00 - Soupapes ou clapets à voies multiples, p. ex. clapets mélangeursRaccords de tuyauteries comportant de tels clapets ou soupapesAménagement d'obturateurs et de voies d'écoulement spécialement conçu pour mélanger les fluides
• F15B 13/04 - Dispositifs de distribution ou d'alimentation du fluide caractérisés par leur adaptation à la commande de servomoteurs pour utilisation avec un servomoteur unique

Abrégé

The invention concerns a dynamic accumulator which is principally used to suppress pressure and flow variations in lines conveying hydraulic energy or fluids. The accumulator uses a mass-spring system in order to attain large-scale dynamic displacement, and consequently to improve the pressurized fluid storage capacity as compared with displacement resulting from the corresponding static pressure. To that end, the adjustment of the resonance frequency of the accumulator is adapted to the speeds at which the pressure and flow vary on the conveying lines. This accumulator both enables the variations to be efficiently suppressed, and it may thus be used in a wide range of applications in new types of pump, and the digital technique of pulse width modulation to be used in the high-precision control of hydraulic actuators. The invention also enables profitability in terms of production and operation to be improved, and the performance and efficiency of the system to be enhanced.

Classes IPC  ?

• F16L 55/04 - Dispositifs amortisseurs de vibrations ou de pulsations dans les fluides

Abrégé

Hydraulic distributors are economical valves in which the resistance to the flow of pressurized oil is minimal; however, they are slow and cannot be controlled rapidly and accurately. In contrast, servo valves and proportional valves are rapid and accurate but also costly and consume large amounts of energy since they are predominantly oil flow choke valves. The hydraulic distributors with rapid change-over between operating positions are economical valves since they do not require a high level of accuracy in operation, are suitable for rapid and high-accuracy control via control techniques such as pulse width modulation, and they do not consume large amounts of energy because the oil passes through the maximum surface area of the apertures therein. These features enable production and operating costs to be reduced and performance to be enhanced. Increasing the mean value of the variation in the pulse width modulation (PWM) control supply with respect to the reaction speed of the main slide enables the position of the slide to be varied such that it acts as a servo valve. The reaction speed of the valve can also be increased in this specific case by reversibly supplying the slide position.

Classes IPC  ?

• F16K 11/00 - Soupapes ou clapets à voies multiples, p. ex. clapets mélangeursRaccords de tuyauteries comportant de tels clapets ou soupapesAménagement d'obturateurs et de voies d'écoulement spécialement conçu pour mélanger les fluides
• F15B 13/043 - Dispositifs de distribution ou d'alimentation du fluide caractérisés par leur adaptation à la commande de servomoteurs pour utilisation avec un servomoteur unique actionnés par la pression du fluide avec clapets-pilotes commandés électriquement

Abrégé

The invention relates to an hydraulic motor comprising at least one camshaft comprising cams having at least one height per rotation of the shaft and a plurality of followers fully surrounding the cams, irrespective of their height. A closed chamber is formed in front of the followers and a control chamber is formed behind the followers. When liquid is injected under pressure into the control chamber, the followers drive the cam, and when the cams drive the followers, the liquid is expelled from the control chamber towards another part of the cycle. An assembly of valves and plugs enables the injection and expulsion of liquid under pressure to be controlled. Inverse torque can be applied to the cams in order to brake the rotation of the shaft or stop it completely, without the intervention of other mechanisms. The shaft may also rotate freely, without the cam movement being coupled to the followers. Controlling the valves and plugs, on the one hand, and integrating a follower-drive mechanism on the cam side during the withdrawal cycle, on the other, enable the device to be used as a pump with a volume of variable geometry. Furthermore, the invention concerns various embodiments with rotation in a single sense or in both senses, and the use of the device as a motor or as an hydraulic pump or as both simultaneously.

Classes IPC  ?

• F04B 1/04 - "Machines" ou pompes multicylindres caractérisées par le nombre ou la disposition des cylindres ayant des cylindres disposés en étoile ou en éventail
• F03C 1/24 - Machines motrices à liquide à pistons alternatifs avec cylindres mobiles dans lesquels le liquide déplace exclusivement un ou plusieurs pistons en mouvement alternatif dans des cylindres rotatifs

Abrégé

Large-aperture rapid non-return valves are used in particular in positive displacement pumps for imparting to the latter greater speed and an improved liquid-pumping rate whilst ensuring a reduced pressure differential, in particular during withdrawal, as well as in similar applications, and for preventing cavitation in the fluid-conveying lines. The method consists in covering the narrow apertures for the flow of liquid with sections of the valve disc or ring during closure, such that the width of the narrow apertures applies the dimensions of the disc or ring sections covering them (even if their thickness is greatly reduced) with a slight pressure differential, and thus produce a tight closure in the closure position. The reduced thickness of the disc or ring provides low inertia, to the benefit of the valve-reaction speed. The long edges surrounding the sections provide the liquid with a large flow area, even when the movement of the valve disc or ring is slight, far from the base thereof. The small movements provide low inertia and the large surface area decreases the loss in pressure of the flow through the large apertures in the open position.

Classes IPC  ?

• F16K 15/00 - Soupapes, clapets ou valves de retenue

Abrégé

The invention relates to a hydraulic positive displacement pump activated by cams which impose on a plurality of followers a movement such that they oscillate about their axis with angular rather than rectilinear momentum. Controlling the control fluid volume enables the geometric volume of this type of pump to be controlled. The pump is characterized in that: the axes help to support some of the force resulting from the effect of the control pressure on the followers during the withdrawal cycle, instead of being supported solely by the regions in which the cams and followers are in contact; the exchange of force in the contact regions increases gradually: it is low when they are first in contact and increases as the withdrawal cycle advances. The axes of the oscillating followers form a movement guide which is far better than that of the rectilinear momentum in terms of ease of production and performance. The invention concerns a novel method enabling mutual stresses in the area of contact between a cam and a follower to be reduced and consists in a groove being produced in the cam, the effect of which is to increase flexibility in the peripheral region, enlarge the area of contact, and hence increase the force-distribution surface. This method may be used in any similar technical application.

Classes IPC  ?

• F04C 2/00 - Machines ou pompes à piston rotatif
• F04C 2/067 - Machines ou pompes à piston rotatif du type à engrènement, c.-à-d. avec un mouvement de translation circulaire des organes coopérants, chaque organe possédant le même nombre de dents ou de parties équivalentes de prise ayant des organes coaxiaux à changement continuel de leur espacement circonférentiel avec un entraînement du type à came et suiveur

Abrégé

The invention concerns embodiments of positive displacement hydraulic pumps in which oil is removed by means of a cam which pushes all the followers surrounding it so as to enlarge the space containing the pump assembly and separating it from the followers. The followers drive the oil from the control area there behind such that it can push the followers of another pump assembly for withdrawal purposes during the pumping stroke. Controlling the amount of oil in the control area enables the geometric volume of the pump to be controlled. The followers of the first embodiments are flexible, while those of the second can slide relative to one another. In addition, bearings can be used in order to attenuate friction and redistribute the cam thrust loads to the followers thereof. Similarly, accumulators can be used to restrict flow and pumping pressure variations.

Classes IPC  ?

• F04C 2/00 - Machines ou pompes à piston rotatif
• F04C 2/067 - Machines ou pompes à piston rotatif du type à engrènement, c.-à-d. avec un mouvement de translation circulaire des organes coopérants, chaque organe possédant le même nombre de dents ou de parties équivalentes de prise ayant des organes coaxiaux à changement continuel de leur espacement circonférentiel avec un entraînement du type à came et suiveur

Abrégé

The invention concerns a two-stage hydraulic servo valve, the regulating control member of which is a stem disposed inside the main control member, which is the main slide. The valve is suitable for medium to high flow rates and can thus replace proportional distributors or servo valves having two or more stages. In the regulating stage of the valve, the apertures are closed in the centre position. The opening of the regulating apertures is brought about as a result of the control stem pivoting on its axis or linearly in the direction of its axis, whilst their closure is brought about by the displacement of the main slide, which enables the auto-feedback position of the main slide to be supplied. The design of the valve is such that it can be used with common torque motors with servo valves for control purposes, or conventional low-cost disc electric motors, or also with piezoelectric motors. In addition, the closure of the apertures in the centre position and the use of conventional control methods enables production, operation and maintenance costs to be reduced and the reaction speed and dynamic output to be considerably improved. Finally, the control valve lends itself to all types of assembly and may have apertures which are open in the centre position.

Classes IPC  ?

• F15B 13/043 - Dispositifs de distribution ou d'alimentation du fluide caractérisés par leur adaptation à la commande de servomoteurs pour utilisation avec un servomoteur unique actionnés par la pression du fluide avec clapets-pilotes commandés électriquement