FR2534323A1 - DEVICE FOR COOLING SPIERS AT THE END OF A MOTOR IN A COMPRESSOR - Google Patents

Abstract

The invention relates to a device for cooling the coils at the end of the engine in a compressor. THIS COOLING DEVICE 14 INCLUDES A COLLECTOR TUBE 28 SOLIDARIZED TO A ROTATING CRANKSHAFT 8 AND OF WHICH ONE END EXTENDS IN A LUBRICANT 12 CRANKCASE. THIS TUBE 28 HAS AN AXIAL BORE 36, AS WELL AS A RADIAL PASSAGE 40 COMMUNICATING WITH THIS , SO THAT WHEN THE CRANKSHAFT 8 IS ROTATING, THE OIL IS PUMPED UP THROUGH THE AXIAL BALEAGE, PART OF THIS OIL BEING PROJECTED OUT THROUGH THE RADIAL PASSAGE AND DIRECTLY AGAINST THE SPIRES LOWER END 24 OF THE STATOR. THE DEVICE OF THE INVENTION IS USED TO COOL THE LOWER COILS AT THE END OF A MOTOR STATOR IN A HERMETIC MOTOR-COMPRESSOR UNIT.

Description

Device for cooling turns in

engine end in a compressor.

  The present invention relates to a device

  cooling system for a motor-com-

  hermetic presser and, more particularly, a

  cooling device that sprays radial-

  part of the lubricant pumped by a collec-

  reader, directly against the lower turns

at the end of the motor stator.

  A problem of major concern

  relating to the hermetic engine-compressor units

  is the heat generated during the operation

  the latter and which reduces the efficiency of

  city of compressor cooling Divers dispar

  Positives were mounted inside the compressor unit housing to pump the lubricant

  an oil pan provided for in the latter and the

  on or against the different structural organs in order to reduce the temperature at which these

  are worn because of the heat generated by

  by the operation of this engine-com-

  An example of such a device is disclosed in US Patent 3,618,337 in which part of the pumped lubricant is used to cool the lower ring at the end of the rotor and then the lower turns to stator tip In particular, the oil flows from the

  oil pan and climbs into a collector tube du-

  which it enters a chamber defined by the inner surfaces of the crown at the end of the rotor,

  a flange of the collector tube which is arranged radially

  as well as the rotating crankshaft

  They extend radially in the crown at the end of the rotor, so that the oil contained in the chamber can flow through these passages and be dispersed against the lower turns at the end of the stator for cooling purposes.

  since the lubricant must first of all

  pouring the household passages into the crowns at the end of the rotor before coming into contact with the lower spirals at the end of the stator, the cooling to which these turns are subjected, is reduced because of the rise in temperature of the lubricant to be measured

  "it flows through the radial passages in

  siping the thermal energy of the crown at the end of the rotor. Another disadvantage of the device described in the aforementioned patent of the United States of America

  3.618 337 is the resulting increase in the cost of

  both of the structure defining the oil chamber, in this case the crown at the end of the rotor, the

  radial flange of the collector tube, as well as the

  fasteners required for

  pulling this radial flange to the lower surfaces of the crown at the end of the rotor, not counting the drilling

  several radial passages in this crown.

  Another device of the prior art

  similar to the above-mentioned device of the

  that earlier is described in the United States Patent

  US Patent 3,560,116 in which oil is distributed in two streams by a pump, one of these streams being used for normal lubrication purposes associated with the parts arranged in the upper region of the housing, while the second current

  is used to directly cool the engine parts.

  Both currents are created by two tubes collec-

  oil pump, namely an inner tube and an outer tube, the outer tube pumping the

  lubricant upward through the defined area

  be the two tubes, to bring it into a chamber -3 defined by the lower crown of short-circuiting

  of the rotor, a flange arranged radially on the

  upper part of the outer tube and the inner tube

  interior that extends upwards towards the city

  In the radial flange, radially arranged grooves are hollowed out in the radial flange and, together with the lower surface of the lower ring-crown, form radial passages for conveying a portion of the lubricant against the lower ends of the stator winding. The cooling to which these ends are subjected

  winding, is reduced, since the oil

  before it is sprayed, has absorbed the thermal energy of the radial flange, the inner collector tube and

  of the lower ring of rotor short-circuiting.

  As is the case with the cooling device

  of the prior art described in the patent

  United States of America 3,618,337, the temperature of

  rotor erosion is generally greater than that of the

  stator, thus further reducing the cooling effect

  the oil exerted on the lower ends

the winding of the stator.

  In addition, the cooling device described in US Pat. No. 3,560,116 inappropriately increases the cost of the compressor because of its rather complex construction for which two collector tubes arranged coaxially, the radial flange, must be provided. disposed on the upper part of the outer collector tube,

  as well as the grooves dug in the radial flange.

  The cooling device of the pre-

  invention removes the disadvantages and

  problems which are mentioned in the technical

  said tube providing a lubricant collecting tube in which is formed a radially disposed hole This hole is located axially on the lubricant collecting tube, so that

  the oil projected radially outwards through

  to this hole does not come into contact with other parts of the engine as it travels to and directly against radial interior surfaces

  lower turns at the end of the stator Given that

  The oil projected radially outwardly through the above-mentioned hole is pumped directly from the lubricant collecting tube out of the crankcase.

  oil, this part of the oil maintains a temperature

  practically constant, so as to ensure maximum cooling of the lower turns at the end of the stator Since this part of the pumped oil does not reach first of all other elements of the

  engine before coming into contact with the lower

  at the end of the stator, the cooling at which

  is subjected by this part of the oil pom-

  is more intense than the resulting cooling

  the use of the cooling devices

cited in the prior art.

  The cooling device of the pre-

  this invention also contrasts with the provisions

  prior art cooling coils in that it is significantly less expensive to produce,

  since it does not involve the use of

  additional structural features, for example,

  radially extending from the upper part of the

  collector tube, throats dug in

  the radial flange, or several

laid coaxially.

  Another advantage of the cooling device

  of the present invention is that it requires less stringent tolerances for

  lower turns at the end of the stator thanks to a

  direct injection of the oil on these end turns,

  thus rendering the immersion of the latter in the oil

  the least critical for controlling the temperatures of the

  as may be the case in some compresses

  in the prior art. In one embodiment of the present

  invention, a motor-compressor group is

  hermetic system, a cooling device

  taking a lubricant collection tube, one of which

  tremité is connected to a rotary crankshaft and

  the opposite end extends into an oil sump

  placed in the housing of the engine-compressor unit.

  This collecting tube comprises an axial bore extending

  upward from its opposite end and through which the oil is pumped from the crankcase.

  lower turns at the end of the motor stator extend

  tooth down, so that their surfaces

  Radial inlets are, in the radial direction, ad-

  adjacent to and spaced from the collector tube In the collector tube, also extends a radial passage

  which communicates with the axial bore and which is

  directly to the lower turns at the end of the stator When the lubricant collecting tube is rotated, part of the lubricant

  pumped upwards through the axial bore is pro-

  thrown radially outward through the pas-

  radially and directly against the surfaces

  radially from the inner turns at the end of the stator before contacting any

other part of the motor group.

  An object of the present invention is to provide, for a hermetic compressor unit, an improved cooling device which conveys a portion of the oil from the housing upward through a lubricant collection tube, for

  then project directly against

  radial ends of the lower turns at the end of the stator before it comes in contact with other

  motor elements by absorbing heat.

  Another object of the present invention is

  to provide a perfect cooling device

  inexpensive manufacturing for the turns

  lower end of a stator in a motor group-

hermetic compressor.

  The above objects and features of the present invention, as well as others as well as how to make them will appear more

  and the invention itself will be better understood.

  read the description below, after a form

  embodiment of the invention given with reference to

  the only appended drawing which is a sectional longitudinal view

  tudinal of the lower part of a motor group-

  hermetic compressor containing a form of embodiment

  preferred embodiment of the present invention.

  Referring to this drawing, the inferior part

  2 of a hermetic motor-compressor unit shown therein, comprises an outer compressor housing 4 which encloses a rotor 6 secured to a crankshaft 8 for rotating therewith, a stator 10 fixed inside the housing 4, a housing

  12 located in the lower part of the box.

  4 and a cooling device

  14 according to the present invention.

  The crankshaft 8 is mounted hastily

  in the engine-compressor unit 2 and contains several passages arranged axially 16, 18 and 20 for conveying the oil to the upper elements of the engine-compressor unit 2.

  oil distributed upwards through the pas-

  16, 18 and 20 is usually recycled to the bus

2534325-

ter 12 by gravity.

  The rotor 6 comprises end rings 22, while the stator 10 comprises turns in

  motor end 24 extending down into the

  4, so that their lower ends can be arranged underneath.

  the oil level 26 in the housing 12.

  The cooling device 14 comprises a collector tube 28 having a generally cylindrical central portion 30, a conical lower portion 32 joined to this median portion 30, and an upper portion 34 disposed within the passage 16 defined in the crankshaft 8 As shown in the drawing, the collecting tube 28 contains an axial bore 36 which communicates with the passage 16

  crankshaft 8 The lower end of the cylinder

  axial geometry 36 defines, in the conical portion 32, an opening 38 which is located below the level

of oil 26.

  Inside the collecting tube 28, is

  swam a 40 hole extending radially and across

  part of the pumped lubricant is projected

  outward-looking feature An im-

  bearing of the cooling device 14 lies in the axial location of the hole 40 in the collecting tube 28 This hole 40 is disposed in the tube

  collector 28 so that it is directed directly

  to the radial inner surfaces 42 of the end turns 24 of the stator, while being situated below the lower surfaces 44 of the end rings 22 of the rotor. By virtue of this location of the hole 40 in the collecting tube 28, the spraying of oil 46 leaving this hole 40 does not encounter any obstacle and is projected directly against the inner radial surfaces 42 of the end turns

24 of the stator.

  An enclosure 48 is attached to the lower portion

  of the outer housing 4 while being arranged

  axially and away from the collecting tube 28 to mitigate the effects of cavitation.

  48 has several holes 50 through which the oil

  the contents of the housing 12 may flow for

culer in the enclosure 48.

  During commissioning, the crankshaft 8 is rotated as soon as the

  engine-compressor unit 2 and it turns the

  be manifold 28 inside the enclosure 48 The oil

  the content in the housing 12 is then sucked upwards through the axial bore 36 from which a portion of this oil continues to rise in the passages 16, 18 and 20 to lubricate the elements

  compressor located in the upper part of the

  The remaining oil pumped upwardly through the axial bore 36 is projected radially outward through

  hole 40 and directly against the surfaces

  42 of the end turns 24 of the stator and that the hole 40 is below

  lower surfaces 44 of the crown 22, the spraying

  The oil reservoir 46 can not contact any part of the engine-compressor unit until it reaches the inner surfaces 42 of the end turns 24 of the stator, thereby virtually eliminating any virtual rise in temperature of the oil spray. which could reduce the cooling of

  turns end 24 of the stator by the device of re-

chilling 14.

  Although the present invention has been described

  referring to a specific embodiment of

  that, it is understood that other modifications may

  to be made accordingly, the present request

  is intended to cover all variants, used

  tions or adaptations of the invention in accordance with

  to the general principles of the latter, and

  globe the departures from this description which

  do not depart from the usual practice or known in the art concerned by the present invention

  and which fall within the scope of the claims

after.

Claims (5)

  1 Compressed hermetic motor-compressor unit   taking an outer dwelling (4) in the bottom of which   a lubricating housing (12), a crankcase   rotating shaft (8) arranged vertically in this box.   and a motor having a stator (10) disposed circumferentially around the rotary crankshaft and a rotor (6) secured to the crankshaft.   rotating to rotate with it, this motor group-   compressor containing a cooling device   (14) comprising: a centrifugal lubricant collecting tube (28)   one end of which is attached to the crankshaft   tative (8) to rotate with the latter and whose ex-   opposite end extends vertically in the lubricant housing (12), this collecting tube (28) enclosing   an axial bore (36) which extends upwards to   firing from the opposite end; the stator (10) has lower turns   at the end (24) which extend downwards in the box-   outer wall (4), the inner radial surfaces (42) of these bottom end turns (24) being,   in the radial direction, adjacent to and spaced from the be collector (28);   the collecting tube (28) encloses a passage   dial (40) communicating with the axial bore (36) and directed directly to the bottom end turns (24) of the stator for projecting a portion of the pumped lubricant upward into the axial bore   r (36), radially outwardly through this step   radially and directly against the surfaces   radial radii (42) of the lower end turns   (24) in order to cool them before entering into   tact with other parts of the engine.   2 Engine-compressor unit according to the   claim 1, characterized in that the lower part   1 top of the lower turns at the end (24) of the stator   (10) is immersed in the lubricant housing (12).   3 Engine-compressor unit according to the   1, characterized in that the diameter of the radial passage (40) is smaller than that of the bore axial geometry (36).   4 Engine-compressor unit according to the   claim 1, characterized in that the radial passage (40) consists of a hole in the tube   collector (28) and located axially below the tor (6).   By proxy of TECUMSEH PRODUCTS COMPANY The proxy is R Baudin