Classifications

• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K41/00—Propulsion systems in which a rigid body is moved along a path due to dynamo-electric interaction between the body and a magnetic field travelling along the path
  • H02K41/02—Linear motors; Sectional motors
  • H02K41/03—Synchronous motors; Motors moving step by step; Reluctance motors
  • H02K41/031—Synchronous motors; Motors moving step by step; Reluctance motors of the permanent magnet type
• • 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
  • B23Q5/00—Driving or feeding mechanisms; Control arrangements therefor
  • B23Q5/02—Driving main working members
  • B23Q5/04—Driving main working members rotary shafts, e.g. working-spindles
  • B23Q5/10—Driving main working members rotary shafts, e.g. working-spindles driven essentially by electrical means
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K16/00—Machines with more than one rotor or stator
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K21/00—Synchronous motors having permanent magnets; Synchronous generators having permanent magnets
  • H02K21/12—Synchronous motors having permanent magnets; Synchronous generators having permanent magnets with stationary armatures and rotating magnets
  • H02K21/22—Synchronous motors having permanent magnets; Synchronous generators having permanent magnets with stationary armatures and rotating magnets with magnets rotating around the armatures, e.g. flywheel magnetos
• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02K—DYNAMO-ELECTRIC MACHINES
  • H02K2201/00—Specific aspects not provided for in the other groups of this subclass relating to the magnetic circuits
  • H02K2201/18—Machines moving with multiple degrees of freedom

Definitions

• This invention pertains to the technology sector of machine tools that perform very high-speed (at sometimes even more than 200,000 rpm) drilling, milling, grinding, etc. operations.
• this invention pertains to an array of electromagnetic motors that are prearranged in a machine in order to ensure the rotational and/or axial movement of a tool-carrying sleeve.
• 99 204 130.1 the same applicant previously described an innovative array in which the movable magnets of a linear motor are attached to the outside of the tool-carrying sleeve, while the stator coils are attached to the inner surface of a hollow member that is coaxially external with respect to the tool-carrying sleeve itself.
• this solution which moreover is implemented in various ways in other examples according to the state of the art, has the drawback that, owing to the above-mentioned high speed of rotation, the movable magnets are subject to stress from elevated centrifugal forces that can, in turn, cause some or all of the magnets to be detached from the substrate to which they are attached. Even the detachment of individual sintered particles can impair operations since said particles remain stuck in the air gap that is present between the movable magnets and the fixed stator coils, thereby exerting a dangerous and damaging "grinding" action on the component parts.
• the inventor of this invention considered it necessary to look for a solution that would avoid the risk of drawbacks similar to those described above. To this end, he has thought up a new way of arranging the various component parts of an array that is composed of the electromagnetic motors.
• the magnets are attached coaxially to the inside of a robust hollow tube that is integral with the tool-carrying sleeve itself, while the coils are attached to the outside of a shaft that is inserted coaxially into said hollow sleeve, whereby said shaft is held firmly in place during operation in order to perform its stator function.
• This solution ensures that the magnets are pushed by centrifugal force against the inner surface of said hollow tube, whereby said centrifugal force exerts a supporting and opposing action that prevents the magnets from moving in the radial direction and prevents individual particles thereof from becoming detached from the magnets in the radial direction.
• the object of invention is an array as described in the preamble to attached Claim 1 , characterized by the statements in the characterizing part of said claim.
• Figure 1 shows a longitudinal section of a portion of a machine tool that contains electromagnetic motors designed according to the state of the art
• Figure 2 shows a longitudinal section of a portion of a machine tool that contains a tool-carrying sleeve in which there is an array according to the invention that contains a linear motor and a rotary motor;
• Figure 3 shows an enlarged cross-section of the most important parts of the array of Figure 2, corresponding to the rotary motor;
• Figure 4 shows the longitudinal section of a portion of a machine tool that contains a tool-carrying sleeve in which the array according to the invention contains only a rotary motor;
• Figure 5 shows the longitudinal section of a tool-carrying spindle, designed according to the state of the art, which has only a rotary motor.
• Figure 2 shows how, in an array 10 according to the invention, a tool-carrying sleeve 19 that is equipped with a tool 20 is attached to a hollow coaxial tube 15, to inner surface 15g of which are attached magnets 11 of a rotary electromagnetic motor 11, as well as magnets 14i of a linear electromagnetic motor 12.
• Stator coils 17 are in turn attached to outer surface 16g of a hollow shaft 16 that is coaxially inside with respect to hollow tube 15, whereby said shaft is held firmly in place while array 10, which contains said two motors 11, 12, is in operation.
• cavity 16e of said hollow shaft 16 it is advantageous to run a coolant by means of a cooling system 18, indicated only in schematic form in the figure, so as to draw off heat that could damage the resins in which coils 17 are embedded or could impair the residual-induction characteristics of magnets 13, 14i.
• FIG. 3 more clearly shows how the basic parts of system 10 of the invention are arranged.
• fixed magnets 13, 14i are attached to inner surface 15g of said hollow tube 15, while stator coils 17 are attached to the outside of a hollow shaft 16, which is internally coaxial.
• said coils 17 are advantageously mounted under outer surface 16g of hollow shaft 16, which on the inside has cavity 16e, the purposes of which were described above .
• Figure 4 illustrates in turn an example where array 10 of the invention is attached to a spindle 22 of the known type that is also equipped with an external cooling system.
• system 10 includes only a rotary electromagnetic motor 11, which is also equipped with magnets 13 that are attached to the inside of a hollow tube 15 and with coils 17 that are attached, as already described above, to the outside of a fixed coaxial hollow shaft 16.

Landscapes

• Engineering & Computer Science (AREA)
• Power Engineering (AREA)
• Mechanical Engineering (AREA)
• Physics & Mathematics (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Electromagnetism (AREA)
• Connection Of Motors, Electrical Generators, Mechanical Devices, And The Like (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

ID=30011701

Family Applications (1)

Country Status (3)

Families Citing this family (3)

Family Cites Families (4)

• 2002
  • 2002-07-15 AU AU2002345307A patent/AU2002345307A1/en not_active Abandoned
  • 2002-07-15 EP EP02743568A patent/EP1563586A1/de not_active Withdrawn
  • 2002-07-15 WO PCT/IB2002/002823 patent/WO2004008613A1/en not_active Application Discontinuation

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events