Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
  • F16C32/00—Bearings not otherwise provided for
  • F16C32/06—Bearings not otherwise provided for with moving member supported by a fluid cushion formed, at least to a large extent, otherwise than by movement of the shaft, e.g. hydrostatic air-cushion bearings
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
  • B23Q—DETAILS, COMPONENTS, OR ACCESSORIES FOR MACHINE TOOLS, e.g. ARRANGEMENTS FOR COPYING OR CONTROLLING; MACHINE TOOLS IN GENERAL CHARACTERISED BY THE CONSTRUCTION OF PARTICULAR DETAILS OR COMPONENTS; COMBINATIONS OR ASSOCIATIONS OF METAL-WORKING MACHINES, NOT DIRECTED TO A PARTICULAR RESULT
  • B23Q1/00—Members which are comprised in the general build-up of a form of machine, particularly relatively large fixed members
  • B23Q1/03—Stationary work or tool supports
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
  • B23Q—DETAILS, COMPONENTS, OR ACCESSORIES FOR MACHINE TOOLS, e.g. ARRANGEMENTS FOR COPYING OR CONTROLLING; MACHINE TOOLS IN GENERAL CHARACTERISED BY THE CONSTRUCTION OF PARTICULAR DETAILS OR COMPONENTS; COMBINATIONS OR ASSOCIATIONS OF METAL-WORKING MACHINES, NOT DIRECTED TO A PARTICULAR RESULT
  • B23Q1/00—Members which are comprised in the general build-up of a form of machine, particularly relatively large fixed members
  • B23Q1/25—Movable or adjustable work or tool supports
  • B23Q1/26—Movable or adjustable work or tool supports characterised by constructional features relating to the co-operation of relatively movable members; Means for preventing relative movement of such members
  • B23Q1/38—Movable or adjustable work or tool supports characterised by constructional features relating to the co-operation of relatively movable members; Means for preventing relative movement of such members using fluid bearings or fluid cushion supports
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
  • B23Q—DETAILS, COMPONENTS, OR ACCESSORIES FOR MACHINE TOOLS, e.g. ARRANGEMENTS FOR COPYING OR CONTROLLING; MACHINE TOOLS IN GENERAL CHARACTERISED BY THE CONSTRUCTION OF PARTICULAR DETAILS OR COMPONENTS; COMBINATIONS OR ASSOCIATIONS OF METAL-WORKING MACHINES, NOT DIRECTED TO A PARTICULAR RESULT
  • B23Q11/00—Accessories fitted to machine tools for keeping tools or parts of the machine in good working condition or for cooling work; Safety devices specially combined with or arranged in, or specially adapted for use in connection with, machine tools
  • B23Q11/0032—Arrangements for preventing or isolating vibrations in parts of the machine
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
  • F16C29/00—Bearings for parts moving only linearly
  • F16C29/02—Sliding-contact bearings
  • F16C29/025—Hydrostatic or aerostatic
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
  • F16F15/00—Suppression of vibrations in systems; Means or arrangements for avoiding or reducing out-of-balance forces, e.g. due to motion
  • F16F15/02—Suppression of vibrations of non-rotating, e.g. reciprocating systems; Suppression of vibrations of rotating systems by use of members not moving with the rotating systems
  • F16F15/023—Suppression of vibrations of non-rotating, e.g. reciprocating systems; Suppression of vibrations of rotating systems by use of members not moving with the rotating systems using fluid means
  • F16F15/0235—Suppression of vibrations of non-rotating, e.g. reciprocating systems; Suppression of vibrations of rotating systems by use of members not moving with the rotating systems using fluid means where a rotating member is in contact with fluid
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
  • F16C2322/00—Apparatus used in shaping articles
  • F16C2322/39—General buildup of machine tools, e.g. spindles, slides, actuators

Definitions

• MECHANICAL DEVICES AND STRUCTURES This invention relates to mechanical devices and structures, and in particular to the damping of vibrations therein.
• this object can be achieved by the provision of a layer of damping material between suitably shaped spaced surfaces of adjacent components of the mounting structure.
• a mechanical structure having a pair of cooperating components separated by a layer of vibration-damping material, wherein the geometry of the interface between said components is adapted so that said damping material will inhibit vibrations of said components.
• the said components are mounted for rectilinear motion relative to one another and are formed with mutually opposed surfaces, for example plane surfaces, extending parallel to the direction of such relative motion with the said damping material disposed in a clearance between them.
• the said components are mounted for rotation, relative to one another, about an axis of rotation, and are formed with mutually opposed surfaces, for example cylindrical surfaces, which are surfaces of rotation about that axis and which have the said damping material disposed in a clearance between them.
• Figure 1 is a front elevational view of a tetrahedral mounting device for a machine tool, a modification of an embodiment of the tool described in U.K. Patent Application No.2194182A;
• Figure 2 is a lateral sectional view, on the line II—II of Figure 1, of the mounting device and machine tool shown in Figure 1 ;
• Figure 3 is a section, on a larger scale, through a workpiece mounting table for the machine tool.
• Figure 4 is a section, on a larger scale, through a toolholder shown in Figures 1 and 2.
• 2194182A includes six rod-like members la - If. Each member comprises a tubular outer strut 2a - 2f enclosing a tensile rod
• each sphere comprises a pair of mating hemispheres 5a - 5d, 6a - 6d.
• the halves of the hemispheres are held together by threaded bolts 7.
• Each sphere abuts the outer strut of three of the rod-like members and is clamped thereto by means of bolts 8 attached to the ends of the corresponding enclosed tensile rod.
• Mounted on the rod-like members la, lb and lc which are remote from the base constituted by members Id, le and If is a machine tool holder 9.
• the machine tool holder is clamped to rod-like members la, lb and lc by means of threaded bolts 10 and space blocks 11.
• the machine tool holder 9 and the hollow sphere 4d have respective bores 12 and 21, coaxial with the machine principal axis 13, through which passes a drive shaft 14 carrying an air bearing spindle having a rotor
• the stator has an extension 15C to provide an extended viscous damping workface
• a vee slideway 17 Mounted on the base rod-like members Id, le and If is a vee slideway 17 bearing a workpiece holder 18 to impart linear motion to a workpiece 19 beneath the grinding tool 16.
• the workpiece holder is provided with a dividing strip 18A.
• Interfaces 18B are provided with a viscous damping medium.
• the slideway has a hollowed-out portion 20 so that the wall thickness is similar to that of the other structural components.
• the hollow sphere remote from the base contains a bore 21 through which the drive shaft passes.
• the geometry of the damping interface can be matched to the modes of the vibration expected or most needing attenuation, for instance the plane vertical damping interfaces between the driving strip of the sliding workpiece holder 18 and the matching slot in the vee slideway 17 will respond efficiently to horizontal mode vibrations from the drive to the sliding workpiece holder and the principal axis (vertical) vibrations; whereas the cylindrical damping interface between the stator of the air bearing rotary spindle 15 and the bore of the machine tool holder 9 will respond efficiently to torsional vibrations from the rotary spindle and to principal axis (vertical) vibrations. Similarly, appropriate vibrational damping may be provided in the spherical coupling between the drive shaft 14 and the rotor 15A.
• the thickness of the viscous damping layer i.e. the gap between the solid surfaces thus comprising the damping interface
• the thickness of the viscous damping layer can be 50 micrometres or greater with suitably high-viscosity damping fluids, so that no tribological (fretting, pick up, wear) problems will arise with dimensional tolerances within normal engineering practice. Close proximity of the two surfaces, as on some existing machines, is not needed; this again avoids tribological problems, and the inconsistent vibration damping which frequently results from stick-slip when the two surfaces are in close proximity or intermittent contact.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Acoustics & Sound (AREA)
• Aviation & Aerospace Engineering (AREA)
• Vibration Prevention Devices (AREA)
• Machine Tool Units (AREA)
• Auxiliary Devices For Machine Tools (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=10648951

Family Applications (1)

Country Status (4)

Families Citing this family (1)

Family Cites Families (11)

• 1988
  • 1988-12-22 GB GB888829945A patent/GB8829945D0/en active Pending
• 1989
  • 1989-12-20 JP JP2500844A patent/JPH04502357A/ja active Pending
  • 1989-12-20 WO PCT/GB1989/001512 patent/WO1990007071A1/en not_active Ceased
  • 1989-12-20 EP EP90900251A patent/EP0449869A1/de not_active Withdrawn

Non-Patent Citations (1)

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