Showing papers on "Damper published in 1975"

Method and apparatus for conservation of energy and containment and evacuation of smoke in a high rise building

Abstract: Apparatus is provided for use in the method of conserving energy by operating a ventilating and air conditioning system in a high rise building in a manner to permit operation of a heating and cooling unit at a reduced percentage of full capacity while adequately heating or cooling the atmosphere within the building. The method is accomplished by cycling area air supply and return dampers between fully-open and intermediate-open positions to selected floors or parts of floors within the building. The dampers are cyclically operated by electro-pneumatic actuators which are operatively connected to a central control apparatus for cycling according to a pre-determined pattern. Smoke detection sensors, located to sample air returned from selected areas of the building to be controlled, supply signals upon actuation by the presence of smoke to the central control apparatus which provides appropriate signals to operate dampers controlling air circulation to the areas of the building where smoke is detected, to create a positive pressure from non-smoke areas of the building toward the smoke area. The smoke is directly evacuated from the building without being recirculated through the air circulating system and the air circulating systems is thereby transformed into a smoke safety, life-support system.

Squeeze Film Dampers: Amplitude Effects at Low Squeeze Numbers

Abstract: Gaseous squeeze film dampers are analyzed to determine the effect of periodic disturbance amplitude on the dynamic performance. Both circular and rectangular parallel surfaces are investigated. A solution of the nonlinear Reynolds equation is obtained by expanding the pressure in powers of the squeeze number, retaining up to and including terms of the order of the square of the squeeze number. The time dependent load characteristics are found. The effect of disturbance amplitude on the film stiffness and damping is given.

Semi-submersible vessels

Abstract: An apparatus for damping vertical movement of a semi-submersible vessel having a small waterplane area, whose buoyancy is provided substantially completely by submerged pontoon means and which includes at least one submerged damper plate having valves or similar flow controllers therein for providing substantially greater resistance to upward movement of the plate than downward movement. The damper plate is supported deep beneath the semi-submersible vessel by flexible, tensioned support elements such as chains or cables, at a depth beneath the water surface in the semi-submerged condition of the vessel, at which depth the amplitude of subsurface wave motion is less than the maximum heave amplitude which would be experienced by the semi-submersible vessel alone under identical sea conditions. The area of the damper plate is several times larger than the waterplane area of the vessel. An upward only-damping action is achieved due to the entrainment of large apparent masses of relatively still water by the damper plate.

Building fresh air ventilator system

Abstract: A fresh air ventilator system for a building or the like having a conditioned air plenum and a return air aperture communicating interiorly of the building, respectively, for circulation of conditioned air within the building, characterized by a ventilator unit disposed in a weather-proof cabinet on a sealing roof curb on the roof of the building. The ventilator unit includes a fresh air inlet adapted to admit fresh air and exclude precipitation and having a fresh air damper for controlling the quantity of fresh air from zero to the maximum; an air circulating blower suitably connected to effect circulation of air through the building; an exhaust means for at least periodically exhausting a portion of the return air; a proportioning damper disposed at the return air aperture for proportioning the amount of return air, from zero to the maximum, fed to the circulating blower; and air conditioning means for conditioning the air to be circulated. Also disclosed are specific preferred structural embodiments, controls, modes and operations; for example, the fresh air inlets, the return air exhaust means, the disposition of the condenser passageway and fan with respect to the fresh air inlet, and the splitter arrangement of the proportioning damper between circulated air and exhaust.

Compact vibration damper

Abstract: A vibration damper for use in a lock-up clutch for a hydraulic torque converter, wherein the clutch provides a direct drive between the engine and transmission of a vehicle in high gear. The vibration damper is designed to be located in a limited space and yet provide relatively large springs for a requisite high torque capacity. The damper is provided with a hub, a driven plate and spring retainer or drive plates; the plates having alternating mounting flanges or legs to be secured to a clutch plate in a common plane and reduce the total thickness of the assembly.

Heave Mode Dynamics of a Tracked Air Cushion Vehicle With Semiactive Airbag Secondary Suspension

Abstract: Bond graph modeling techniques are used to develop a fully nonlinear heave mode model of a tracked air cushion vehicle incorporating a semiactive airbag secondary suspension The governing state space equations were simulated for various deterministic guideway inputs and comparisons were made with the exact solution of the linearized equations An experimental test stand is described which provides experimental corroboration of the mathematical models for the case of totally passive secondary suspension elements Theoretical results are presented which demonstrate the superior vehicle ride characteristics with respect to passenger-guideway isolation provided by the combination of soft airbag springs and semiactive dampers

Vibration damper for high voltage cables

Abstract: Improved multiple mode dampers for damping Aeolian vibrations of electrical cables are provided which employ a single mass and two resilient support members that are respectively connected between separate points of the mass and separate points of the cable. The modes of vibration of the damper are made interdependent by utilizing springs having different moments of stiffness with respect to the center of gravity of the mass. The mass is made of concrete. The improvement comprises the use of springs which are independently connected to the cable at different points permitting the spreading of the springs which can be accomplished economically and yet permit an increase of the rotational torque exerted on the damper by the cable. This facilitates concentration of damper vibration resonance frequencies at critical wind speeds which would ordinarily induce great dynamic mechanical stress in electrical cables.

Refrigerator food conditioning appliance

Abstract: A food receptacle for a refrigerator freezer compartment for fast-thawing and fast freezing food by the use of a concavo-convex heat energy reflective damper pivotally mounted in an air passage of the receptacle which communicates with an opening in the refrigerated air duct of the compartment. A high energy radiating lamp is located on the pivotal axis of the damper such that a manual control pivots the damper to a first evaporator defrost position closing the passage with the damper operative to direct heat energy from the lamp via reflective surfaces in the duct to the refrigerator cooling coil. The damper upon being pivoted to a second position, opens the passage and cooperates with the duct reflective surfaces to circulate below freezing air through the receptacle to fast freeze food therein. The damper, upon being pivoted to a third position, closes the passage and reflects heat energy from the lamp into the receptacle to fast-thaw food therein.

Redundant damper seals

Abstract: A cylinder-and-piston type hydraulic damper has spaced dual seals on its piston rods to provide annular cavities between seals. A fluid leakage line connects said cavities to the closed reservoir of a fluid leakage indicator which consists of a cylinder closed by a spring biased diaphragm which carries the indicating member of the indicator. The damper chambers on opposite sides of the piston are alternately supplied with fluid from the reservoir during operation of the damper by means of a shuttle valve, thus providing a closed and sealed fluid system including redundant seals with means for indicating that the damper needs servicing upon a predetermined loss of fluid from the reservoir.

Design and application of squeeze film dampers for turbomachinery stabilization

Abstract: The steady-state transient response of the squeeze film damper bearing was investigated. Both the steady-state and transient equations for the hydrodynamic bearing forces are derived; the steady-state equations were used to determine the damper equivalent stiffness and damping coefficients. These coefficients are used to find the damper configuration which will provide the optimum support characteristics based on a stability analysis of the rotor-bearing system. The effects of end seals and cavitated fluid film are included. The transient analysis of rotor-bearing systems was conducted by coupling the damping and rotor equations and integrating forward in time. The effects of unbalance, cavitation, and retainer springs are included. Methods of determining the stability of a rotor-bearing system under the influence of aerodynamic forces and internal shaft friction are discussed.

Suspension strut assemblies for motor vehicle suspensions

Abstract: A suspension strut assembly for a motor vehicle suspension including a telescopic damper which is connected at its ends to a wheel carrier and to part of the vehicle superstructure, and a wheel suspension spring which surrounds the damper and is seated at one end on a casing portion of the damper and at the other end effectively on a piston rod of the damper. To facilitate replacement of worn parts without the need to dismount the entire strut, the connection of the damper to the vehicle superstructure is effected by means of an intermediate member having a bayonet-type or other form of releasable connection to an appropriately shaped aperture in the superstructure such that on release the intermediate member can be lifted out through the aperture, as can the inner part of a two-part thrust plate for the suspension spring, and a ring nut giving access to the internal parts of the damper.

Design of a Squeeze-Film Damper for a Multi-Mass Flexible Rotor

Abstract: A single mass flexible rotor analysis was used to optimize the stiffness and damping of a flexible support for a symmetric five-mass rotor. The flexible support attenuates the rotor motions and forces transmitted to the support bearings when the rotor operates through and above its first bending critical speed. An oil squeeze-film damper was designed based on short bearing lubrication theory. The damper design was verified by an unbalance response computer program. Rotor amplitudes were reduced by a factor of 16 and loads reduced by a factor of 36 compared with the same rotor on rigid bearing supports.

Experimental Measurement of the Dynamic Force Response of a Squeeze-Film Bearing Damper

Abstract: 4,669,893 6/1987 Chalaire et al. ...................... 384/99 4,775,248 10/1988 Barbic et al. .......................... 384/99 4,782,919 1/1988 Chalaire et al. ...................... 384/99 4,783,179 11/1988 Katayama et al. 384/30 4,947,639 8/1990 Hibner et al. ... 384/99 4,992,024 2/1991 Heydrich .............................. 384/99 |||||||||||||| USOO5149206A 11) Patent Number: 5,149,206 (45) Date of Patent: Sep. 22, 1992

Automatic air flow control

Abstract: An automatic air flow control system for a solar heating installation wherein thermostatically controlled dampers are associated with such solar heating elements as the collector and the storage area, and with the rooms to be heated, the thermostats being pre-settable to program their operations, with minimal supervision, in response to variable heat supply at the collector and variable heat demand in the rooms to be heated.

The application of impact dampers to continuous systems

Abstract: A study has been made of the application of impact dampers to two types of continuous systems, a simply supported and a clamped beam. Previous efforts have included the effect of impact dampers on single degree of freedom and other systems with finite numbers of degrees of freedom. Experimental models were tested in the laboratory and finite element computer programs were developed to calculate response. Results from calculations agree favorably with experimental tests. Further, results from the first few natural modes also compare reasonably with data published on systems with finite number of degrees of freedom. Curves are presented which enable the user to apply impact dampers to these types of continuous systems. Curves show the amount of the isolation to be expected for values of significant system parameters.

Device for suspending the body and the engine-drive unit in an automobile vehicle

Abstract: Two series of separate elastically yieldable blocks having different stiffnesses are disposed between the damper and the vehicle body and between the damper and the engine-drive unit. The accelerations transmitted to the body and to the engine are then substantially equal. In this way, the relative movements between the engine-drive unit and the body and the resulting vibrations are reduced while the noises transmitted by the engine through its suspension are also reduced.

Automatic stack damper

Abstract: An improvement in a system comprising a heat stack, a damper having a vane in said heat stack, actuating means for opening and closing said damper, the actuating means being electrically connected to and responsive to a thermostat in an electrical circuit containing the heating means for generating heat, the by-products from which pass through the heat stack, the improvement residing in that the actuating means comprises an electric motor which is spring biasedly connected to the vane, the electric motor being in a normally "On" position having current passing therethrough and holding said vane against the action of said spring in a closed position. Means are provided to deactivate the motor and allow the spring to return the vane so that the stack is in an open position.

Torsional vibration damper

Abstract: A hub element of the vibration damper is adapted for connection to a shaft and has a first circumferentially extending support surface. An inertia element surrounds the hub element and has a circumferentially extending second support surface. An elastomeric member is compressed between these surfaces and mounts the inertia element on the hub element with freedom of vibration. An arrangement is provided on one or the other of the elements for continuously varying the characteristic frequency of vibration of the damper, by subjecting the elastomeric member in axial or radial direction to continuously variable compression.

Steady-state and transient analysis of a squeeze film damper bearing for rotor stability

Abstract: A study of the steady-state and transient response of the squeeze film damper bearing is presented. Both the steady-state and transient equations for the hydrodynamic bearing forces are derived. The bearing equivalent stiffness and damping coefficients are determined by steady-state equations. These coefficients are used to find the bearing configuration which will provide the optimum support characteristics based on a stability analysis of the rotor-bearing system. The transient analysis of rotor-bearing systems is performed by coupling the bearing and journal equations and integrating forward in time. The effects of unbalance, cavitation, and retainer springs are included in the analysis. Methods of determining the stability of a rotor-bearing system under the influence of aerodynamic forces and internal shaft friction are discussed with emphasis on solving the system characteristic frequency equation and on producing stability maps. It is shown that for optimum stability and low force transmissability the squeeze bearing should operate at an eccentricity ratio epsilon 0.4.

Vehicle pyrolytic gas generator - with particle separator comprising centrifugal circular chamber in bag safety system

Abstract: A compact pyrolytic gas generator is described with integral particle separator and sound damper. The gas is generated by a charge in a cylindrical housing surrounded by a circular duct into which the pyrolytic gasses are ejected via tangential tubes. The gasses swirl around the chamber while an angled deflecting wall at the bottom guides the particles in the gas stream into a collecting chamber at the bottom of the system. An upper deflecting wall separates the chamber from the outlet which is sealed with a filter plug. The system is compact and provides a controlled, purified, and cooled gas discharge with a minimum of sound.

Furniture sliding drawer arrangement - includes end stop acting as spring loaded damper

Abstract: Extension fitting for sliding drawer of modular wall furniture. Drawers which runs on rollers in support rails, contacts at the end of the running track a spring loaded damper arrangement, the spring loaded damper is provided with a throttle arrangement. The spring loaded damper arrangement includes a horizontal positioned piston with conical head. The piston may be of the mandrel type and has on the side towards the cylinder an annular ring in which an O-ring is embedded. In the damper arrangement be incorporated a capillary tube with needle valve, and a non-return valve opens when vacuum is present in the cylinder.

Vibrating Beam Dampers for Reducing Vibrations in Gas Turbine Blades

Abstract: This paper reports the results of a preliminary investigation of the feasibility of reducing vibratory response levels in jet engine turbine blades by means of tuned damping devices incorporating high temperature vitreous enamels for energy dissipation. It is shown that an externally coated cantilever beam damper can be very effective in reducing vibration amplitudes, provided that it is properly tuned. Further efforts are needed to develop and verify an engineering design which will satisfy all operational requirements. The first step in that direction, which should be the next phase of the investigation, is to verify that the enamels and dampers considered in this paper will withstand the centrifugal loads imposed by rotation of the blades.

Cantilever for pickup cartridges

Abstract: Method of making cantilever by laminating carbon fibres on aluminium pipe …Aluminium cantilever vertical elastic ratio E 7000kg/mm2 is small while density 27 is rather big Hence the frequency responses of conventional cartridges with aluminium cantilevers has sags in the middle to high frequency range Carbon fibre cantilever with high rigidity (can be made very light as cantilever, extending the high resonance frequency) …Fig1: Conventional stylus with aluminium pipe cantilever …Fig2: Section of cartridge having invented cantilever …Fig3: Section of invented cantilever …Fig4: Frequency responses of conventional and invented cantilever with 1 conventional aluminium cantilever, 2 tip, 3 magnet, 11 invented carbon fibre cantilever, 11a aluminium pipe, 11b layer of carbon fibres, 12 stylus, 13 magnet, 14 pole pieces, 15 coils, 16 damper, 17 sag with conventional cantilever, 18 improved response by using invented cantilever, 19 separation with conventional cantilever, 20 separation available with invented cantilever

Controlled crop drying attachment for combine

Abstract: A heat exchanger is mounted to the combine and receives waste heat from the combine engine. A blower is mounted to the combine and sucks ambient air through the heat exchanger to heat the air and blows the heated air into a closed end duct that has a portion mounted in the combine crop hopper. The portion of the closed end duct mounted in the crop hopper has a plurality of perforations therein so that the heated air can dry the combined crops. An apparatus is provided for controlling the temperature of the air blown into the combined crops including a damper for supplying a desired mixture of ambient air and heated air to the closed end duct. A transducer mounted in the closed end duct and a transducer responsive damper actuating apparatus moves the damper in response to the transducer response to the temperature of the air passing the transducer. The transducer responsive damper actuating apparatus is shown as a mechanical, pneumatic and electrical apparatus.

Seismic motion-damper for upstanding electrical equipment

Abstract: A seismic damper device is provided between the supporting plate adjacent the bottom of an upstanding piece of electrical apparatus and the lower main frame support members, supporting said upstanding electrical equipment, so that any relative motion between the upstanding column structure and the main lower-disposed frame support structure is restricted. Preferably, a liquid-filled dash-pot assembly, or energy-absorbing device, is utilized at one or more locations extending between the lower supporting plate member of each upstanding column structure and the lower-disposed main supporting framework. In one form of the invention there are provided three equally-spaced radially-extending support arms extending outwardly from the main supporting plate disposed adjacent and fixed to the lower end of each upstanding column structure. A hydraulic damper assembly is provided for each support arm and has its upper end secured to the outer end of the particular support arm, and the other end of the said damper assembly is attached to the main lower disposed supporting framework structure of the electrical equipment. Any relative motion between the radially-outwardly-extending support arms and the lower-disposed main supporting framework structure causes a hydraulic piston to move within a damper cylinder; provided in each of the three damper assemblies and damping is effected by the displacement of hydraulic liquid, for example, from one side of a piston member in each of the three damper assemblies to the other side thereof through small orifices provided in each damper assembly, for example.

Rubber torsional vibration damper with cooling means

Abstract: A vibration damper for rotating members consists of a hub member joined to an inertia member by a plurality of elastic elements Cooling fins on the inertia member and between the elastic element provide for dissipation of heat from the inertia member and the elastic elements The cooling fins are parallel to the side surfaces of the insertia member In an alternate embodiment, the cooling fins are angled to the side surfaces of the inertia member to augment the cooling effect of integral fins therein In further alternate embodiments the hub member is bifurcated and the cooling fins and elastic member are oriented at angles to the axis of rotation of the hub

Stack damper control arrangement

Abstract: A stack damper control arrangement for use in a heating system including a furnace having a fuel-fired burner apparatus and a vent stack for conducting combustion products away from the burner apparatus and a damper plate pivotally mounted within the stack and movable between a fully open and a fully closed position, includes a reversible drive motor which is energizable in response to a request for heat to drive the damper plate to the open position, a first limit switch operated when the damper plate reaches the open position to effect the deenergization of the motor, the motor being reenergized at the end of the heating cycle to drive the damper plate to the closed position, and a second limit switch operated when the damper plate reaches the closed position to effect the deenergization of the motor. The damper control arrangement is described with reference to a heating system including a gas fired burner and redundant gas valves wherein operation of a first one of the gas valves is effected through operation of the first limit switch and thus is conditional upon the damper being fully open, and wherein the supply of fuel to the second valve is conditional upon the operation of the first valve.

Air processing apparatus

Abstract: The present invention pertains to an air processing system for an enclosed area having a plenum. The system includes an air processing means in communication with the plenum and responsive to a temperature sensing means, air-passing light fixtures for lighting the enclosed area, return air means through which the air processing means receives return air via two separate paths, one being in heat exchange relationship with the light fixtures, damper means for controlling the passage of air through the return air means, power exhaust means and ventilation means for exhausting air from the plenum and enclosure to achieve volume balance. The damper means is constructed and arranged so as to maximize the use of heat from the light fixtures whenever heating is required in the enclosed area and to discharge heat from the light fixtures to the atmosphere whenever cooling is required to reduce the cooling requirement.