JP2014092120A - Driving device - Google Patents

Abstract

Provided is a drive device capable of stably securing a supply amount of lubricating oil even when the rotational speed of a rotary shaft is lowered.
The drive device includes a casing, a drive unit having a rotary shaft, an oil reservoir, and an oil supply pump. The rotary shaft has an inlet and an outlet. A flow path 45 is formed, and the oil supply pump 17 is fixed to the outer periphery of the lower end portion of the rotary shaft 40, has an inner diameter larger than the outer diameter, and has a cylindrical sleeve 50 that is open at the bottom, and the rotary shaft. An insertion shaft 60 having an outer diameter larger than the outer diameter of the sleeve 50 and smaller than the inner diameter of the sleeve 50, inserted into the inner periphery of the sleeve from the lower opening of the sleeve 50, and fixedly supported in the casing 11. A spiral groove 62 is formed on the outer periphery of 60.
[Selection] Figure 1

Description

  The present invention relates to a drive device that includes a drive unit having a rotating shaft and an oil supply pump that supplies lubricating oil to a sliding portion of the drive unit.

  For example, a compressor such as a reciprocating compressor or a scroll compressor, a turbine generator, or the like includes a drive unit having a rotation shaft, and the rotation shaft of the drive unit rotates, so that a piston, a scroll, and a turbine blade Etc. perform predetermined operations. Lubricating oil for improving lubricity is supplied to a sliding portion of a driving unit of these apparatuses by an oil supply pump.

  As a drive device having a drive unit having a rotating shaft and an oil supply pump, for example, Patent Document 1 listed below includes a sealed container, a compression mechanism unit having a fixed scroll and a turning scroll, and a drive unit for driving the turning scroll to turn. A scroll compressor having a rotary shaft arranged in a vertical direction of the sealed container and provided with an oil supply pump for supplying oil to the compression mechanism unit at a lower end side of the rotary shaft is described. Yes.

  The oil pump is a so-called trochoid pump composed of a trochoidal toothed inner rotor and an outer rotor. When the outer rotor rotates as the inner rotor rotates, oil is sucked from the lower surface of the oil pump and supplied to the rotating shaft. It has come to be.

  In Patent Document 2 below, a sealed container, a first fixed scroll, a swing scroll, a second fixed scroll disposed on the lower surface side of the swing scroll, a first bearing portion of the first fixed scroll, and A scroll fluid machine is described that has a main shaft that is pivotally supported by a second bearing portion of a second fixed scroll and that extends through the rocking bearing portion of the orbiting scroll and extends vertically in a sealed container. .

  The main shaft extends with a constant diameter, and an oil supply passage extending vertically is formed inside. A spiral groove is provided on the outer periphery above the oil supply passage, and a lubrication groove is provided at the lower end of the main shaft. An oil pump for supplying oil to each bearing portion is attached. When the main shaft rotates, the lubricating oil at the bottom of the sealed container rises in the oil supply passage by utilizing centrifugal force in the oil pump, and is pumped to the lower end side of the first bearing portion, and part thereof Rises through the spiral groove and is transferred to the upper space of the sealed container.

  Patent Document 3 below discloses a sealed container, a block having a cylinder, a piston that reciprocates in the cylinder, a shaft that is rotatably supported by a bearing of the block, and a lower end portion of the shaft. A compressor having a viscous pump formed on the side is described.

  In Embodiment 7 described in paragraphs 0164 to 0177 of Patent Document 3, the viscous pump is fixed to a cylindrical cavity formed inside the shaft and an inner periphery of a lower opening of the cylindrical cavity. A hollow sleeve, a columnar insertion member that is coaxially inserted into the sleeve and the cylindrical cavity, and extends at a constant diameter, and is provided on the inner periphery of the sleeve or the outer periphery of the insertion member, and the direction in which the lubricating oil rises And a suppressing means for suppressing the rotation of the insertion member. When the shaft rotates, the lubricating oil rises through the spiral groove between the sleeve and the insertion member, and is transferred to the cylinder side.

JP 2009-236062 A JP 2009-167913 A International Publication WO 2004/081383 Pamphlet

  With the recent demand for energy saving, the drive device such as the compressor is also driven by an inverter, and the rotational speed of the rotary shaft tends to be kept low. For this reason, in the structure in which the pump is operated by the centrifugal force generated by the rotation of the shaft as in the above-mentioned Patent Document 2, the power of the pump tends to be insufficient, so that the amount of lubricating oil supplied decreases and the drive unit slides. In some cases, the lubrication performance at the location tends to be lowered.

  On the other hand, the scroll compressor disclosed in Patent Document 1 employs a positive displacement trochoid pump that does not use centrifugal force. Therefore, the scroll compressor is less affected by the rotational speed of the rotating shaft and supplies a certain amount of fluid. However, since the trochoidal tooth profile is complicated and processing accuracy is required, there is a demerit that the cost is high.

  Further, in Patent Document 3, by providing a spiral groove on the inner periphery of the sleeve or the outer periphery of the insertion member, the contact area with the oil is increased by the amount corresponding to the recess of the spiral groove, and the viscosity resistance is increased to increase the oil conveying capability. An improvement is described (see paragraph 0067).

  However, since the sleeve is fixed to the inner periphery of the lower opening of the cylindrical cavity provided in the shaft, the inner diameter of the sleeve cannot be increased, and the outer diameter of the columnar insertion member inserted into the sleeve However, the increase in the supply amount of the lubricating oil cannot be expected so much. Furthermore, since it is necessary to provide a cylindrical cavity inside the shaft, there is a problem that the strength of the shaft is reduced.

  Further, in Patent Document 3, a spiral groove is provided on the outer periphery of the main shaft. The spiral groove is formed above the oil supply passage provided in the main shaft and is attached to the lower end of the main shaft. It does not contribute to an increase in the amount of lubricating oil supplied by the oil pump.

  Therefore, an object of the present invention is to provide a drive device that can stably secure the supply amount of lubricating oil even when the rotational speed of the rotary shaft is lowered.

  In order to achieve the above object, a drive device according to the present invention is provided in a casing, a drive unit, an oil reservoir provided in the bottom of the casing, and the oil reservoir that is operated by the power of the drive unit. An oil supply pump, wherein the oil supply pump is configured to supply lubricating oil to a predetermined sliding portion of the drive unit, the drive unit has a rotation shaft, and the rotation shaft has a lower end portion thereof. It extends to reach the oil reservoir, and has a lubricating oil flow path therein. The flow path is provided at the lower end of the rotating shaft, and the lubricating oil inlet and the rotating shaft. An outlet for supplying lubricating oil to the sliding portion provided at a predetermined location, and the oil supply pump has an outer periphery of a lower end portion of the rotating shaft without closing the inlet of the rotating shaft. Fixed to the said times A cylindrical sleeve having an inner diameter larger than the outer diameter of the shaft and opened at the bottom; an outer diameter larger than the outer diameter of the rotating shaft and smaller than the inner diameter of the sleeve; An insertion shaft that is coaxially disposed and is inserted into the inner periphery of the sleeve from a lower opening of the sleeve and is fixedly supported in the casing, and is spirally disposed on the inner periphery of the sleeve or the outer periphery of the insertion shaft. The present invention provides a driving device characterized in that a groove is formed.

  According to the above invention, a screw pump is formed by the sleeve fixed to the lower end portion of the rotating shaft and the insertion shaft fixedly supported in the casing and inserted into the sleeve. That is, when the sleeve rotates integrally with the rotating shaft, the oil that has entered the gap between the rotating sleeve and the fixedly arranged insertion shaft receives frictional force due to the rotation of the sleeve, and the inner circumference of the sleeve or the outer circumference of the insertion shaft. It moves toward the inflow port side of the rotating shaft along the spiral groove formed on the rotating shaft.

  As a result, the oil in the oil reservoir is sucked into the oil supply pump, introduced from the inlet of the rotary shaft into the flow path formed inside the rotary shaft, and flows out from the outlet formed at a predetermined position of the rotary shaft. , Supplied to the sliding portion of the drive unit.

  The sleeve has an inner diameter larger than the outer diameter of the rotating shaft, and the insertion shaft has an outer diameter larger than the outer diameter of the rotating shaft and smaller than the inner diameter of the sleeve. The length of the flow path through the groove) can be increased, the centrifugal force acting on the lubricating oil can be increased, and the flow rate of the pump can be increased. As a result, the necessary flow rate of the lubricating oil can be ensured even if the rotational speed of the rotating shaft is slowed down due to inverterization or the like.

  Also, a sleeve having a larger inner diameter is fixed to the outer periphery of the lower end of the rotating shaft, an insertion shaft is inserted into the lower opening of the sleeve, and a spiral groove is provided on the sleeve inner periphery or the insertion shaft outer periphery. And since the screw pump was comprised by these, it is not necessary to provide a large hole in the lower end part of a rotating shaft, and the intensity | strength can be maintained.

  In the drive device of the present invention, the casing forms a sealed space inside, and has a fluid suction portion and a discharge portion, and the drive portion includes a drive mechanism portion having the rotating shaft, Preferably, the compressor has a compression mechanism that is driven by a rotary shaft and compresses the fluid sucked from the suction portion and discharges the fluid from the discharge portion, and is used as a compressor.

  According to this, when the rotating shaft is rotated by the drive mechanism portion, the compression mechanism portion is driven, and the fluid introduced into the casing from the suction portion is compressed and discharged from the discharge portion. Also, oil in the oil reservoir is sucked into the oil supply pump, introduced from the inlet of the rotating shaft into the flow path formed inside the rotating shaft, and flows out from the outlet formed at the upper part of the rotating shaft to slide. Supplied to the moving part.

  In the driving device according to the present invention, the insertion shaft has a concave portion opened upward at a central portion thereof, and a shaft portion extending toward the lower opening is provided at a central portion of the inner end surface of the sleeve, The shaft portion is inserted into the recess of the insertion shaft, and the inlet of the rotary shaft communicates with a flow path that opens to the lower end through the center of the shaft portion, and the inner periphery of the recess or the It is preferable that a second spiral groove is formed on the outer periphery of the shaft portion.

  According to this, a first screw pump having a spiral groove is formed between the inner periphery of the sleeve and the outer periphery of the insertion shaft, and a second screw pump having the same spiral groove between the recess and the shaft portion is formed. Since the oil in the oil reservoir is formed and introduced into the inlet of the rotary shaft through the first screw pump and the second screw pump, the substantial length of the screw pump can be increased. The flow rate of the pump can be further increased.

  In the drive device according to the present invention, it is preferable that the flow path of the rotating shaft has an inner diameter that is expanded toward the inlet near the inlet. According to this, the lubricating oil sucked by the screw pump formed by the sleeve and the insertion shaft can easily flow into the inlet of the rotating shaft.

  In the drive device of the present invention, it is preferable that the flow path of the shaft portion communicating with the inlet of the rotary shaft has an inner diameter that is expanded toward the lower end opening. According to this, the lubricating oil sucked by the first screw pump formed between the sleeve and the insertion shaft can easily flow into the lower end opening of the insertion shaft through the second screw pump. .

  According to the present invention, since the inner diameter of the sleeve constituting the screw pump is larger than the outer diameter of the rotating shaft and the outer diameter of the insertion shaft is larger than the outer diameter of the rotating shaft, the substantial length of the screw pump can be increased. The centrifugal force acting on the lubricating oil can be increased. As a result, the flow rate of the pump can be increased, and the outer diameter of the rotating shaft can be secured to maintain the strength.

It is a schematic structure figure showing one embodiment which applied the drive concerning the present invention to a compressor. It is principal part expansion explanatory drawing of the drive device. It is explanatory drawing explaining the theoretical flow volume of a screw pump. It is principal part expansion explanatory drawing which shows other embodiment of the drive device which concerns on this invention. It is a principal part expansion explanatory drawing which shows other embodiment of the drive device which concerns on this invention.

  Hereinafter, an embodiment of a drive device according to the present invention will be described with reference to the drawings.

  As shown in FIG. 1, a drive device 10 in this embodiment is used as a compressor for compressing a fluid such as air or refrigerant, and includes a casing 11 and a drive disposed in the casing 11. It is mainly comprised from the part 15 and the oil supply pump 17 which supplies the lubricating oil O to the predetermined sliding location of this drive part 15. As shown in FIG.

  The casing 11 has a sealed space 12 formed therein, and an oil reservoir 13 is provided at the bottom thereof. A predetermined amount of lubricating oil O is stored in the oil reservoir 13.

  The drive unit 15 includes a drive mechanism unit 20 disposed on the lower side in the casing 11 and a compression mechanism unit 30 disposed on the drive mechanism unit 20.

  The drive mechanism 20 is elastically supported by a support frame 25 via a spring 22 supported by support protrusions 22a and 22b formed at the bottom of the casing 11, and a stator 21 fixed to the support frame 25. It is comprised with the electric motor which has the rotor 23 supported so that rotation inside the stator 21 was possible. A shaft fixing hole 26 is formed at the center of the rotor 23, and a shaft support recess 27 having a diameter larger than that of the shaft fixing hole 26 is formed above the shaft fixing hole 26. The rotating shaft 40 which has a portion oriented in the vertical direction is fixed. As a result, when the rotor 23 is rotated by a driving source (not shown), the rotating shaft 40 is rotated.

  The rotating shaft 40 extends so that the lower end reaches the oil reservoir 13, and a plate-like crank web 41 is connected to the upper end of the rotating shaft 40. An eccentric shaft 43 protrudes at a position eccentric with respect to the axis of the rotary shaft 40.

  A flow path 45 for the lubricating oil O is formed inside the rotary shaft 40. The flow path 45 has an inlet 46 provided at the lower end of the shaft and an outlet 47 provided at the upper end of the shaft and through which the lubricating oil O flows out to the compression mechanism 30 side. Further, as shown in FIG. 2, the inner peripheral surface 46a of the inflow port 46 has a tapered shape with a diameter gradually increasing toward the lower end portion of the shaft.

  On the other hand, the compression mechanism section 30 has a cylinder block 31 supported on the drive mechanism section 20 via a support member 32 and a piston 33 that reciprocates within the cylinder block 31.

  The cylinder block 31 is arranged in a horizontal direction, and a cylinder 31a in which the piston 33 reciprocates, and extends downward from the lower surface of the cylinder 31a. The cylinder block 31 is inserted into and supported by the shaft support recess 27 of the rotor 23. Holder 31b. A rotating shaft 40 is inserted into the holder 31b and connected to the crank web 41 disposed in the upper opening of the holder 31b.

  The piston 33 is connected via a connecting rod 34 to an eccentric shaft 43 attached to the rotary shaft 40 via a crank web 41. As a result, when the rotary shaft 40 rotates and the eccentric shaft 43 rotates via the crank web 41, the piston 33 reciprocates in the cylinder 31a via the connecting rod 34.

  One side opening of the cylinder 31a is closed by a cylinder head 36 via a valve plate 35 having a valve mechanism (not shown), thereby forming a compression chamber 37. A suction pipe 38 communicating with the outside of the casing is connected to the compression chamber 37 via the valve plate 35, so that fluid is sucked into the compression chamber 37 from the outside. Further, a discharge pipe 39 communicating with the outside of the casing is connected to the compression chamber 37 via a valve mechanism (not shown), and the fluid compressed by the piston 33 is discharged to the outside in the compression chamber 37. ing. The suction pipe 38 forms the “suction part” of the present invention, and the discharge pipe 39 forms the “discharge part” of the present invention.

  Next, the oil pump 17 will be described with reference to FIG. 2. The oil pump 17 is fixed to the outer periphery of the lower end of the rotary shaft 40 without closing the inlet 46 of the rotary shaft 40, and the lower part is open. A cylindrical sleeve 50 and an insertion shaft 60 which is inserted from the lower opening of the sleeve 50 and fixedly supported in the casing 11.

  The sleeve 50 includes a circular ceiling plate 51 having a shaft insertion hole 51a formed in the center, and a cylindrical wall 52 extending downward from the periphery of the ceiling plate 51, and has a cylindrical shape with an opening at the bottom. ing.

  The inner diameter D2 of the cylindrical wall 52 is formed larger than the outer diameter D1 of the rotary shaft 40.

  Then, the lower end portion of the rotating shaft 40 is inserted into the shaft insertion hole 51a, and is screwed into a screw groove (not shown) on the outer periphery of the rotating shaft with a pair of nuts 53, 53 arranged above and below the ceiling plate 51, A sleeve 50 is fixed to the outer periphery of the lower end portion of the rotary shaft 40 with screws. As a result, when the rotary shaft 40 rotates as the rotor 23 rotates, the sleeve 50 rotates together with the rotary shaft 40.

  The means for fixing the sleeve 50 to the outer periphery of the lower end portion of the rotary shaft 40 is not limited to fastening by the nut 53 but may be fixed by welding, caulking, adhesive, or the like, for example. .

  On the other hand, the insertion shaft 60 is formed with an outer diameter D3 that is larger than the outer diameter D1 of the rotary shaft 40 and smaller than the inner diameter D2 of the cylindrical wall 52 of the sleeve 50. It has a so-called screw shaft shape in which a spiral groove 62 is provided through a spiral protrusion 61 protruding at a predetermined pitch.

  The insertion shaft 60 is inserted from a lower opening of the sleeve 50 so as to be spaced from the inner periphery of the cylindrical wall 52 of the sleeve 50 and coaxial with the rotary shaft 40. It has come to be. Further, as shown in FIG. 1, the lower end portion of the insertion shaft 60 is supported by the support member 65 attached to the support frame 25 of the drive mechanism portion 20 so that the insertion shaft 60 does not rotate. It comes to be fixedly supported by. Here, the term “fixed support” means fixed support relative to the rotation of the rotary shaft 40 and the sleeve 50, and swings with the support frame 25 elastically supported via the spring 22. That means unimpeded.

  Then, when the sleeve 50 rotates integrally with the rotary shaft 40 by the rotation of the rotor 23, the lubricating oil O that has entered the gap between the inner periphery of the sleeve 50 and the outer periphery of the insertion shaft 60 generates frictional force due to the rotation of the sleeve 50. 2, the spiral of the spiral groove 62 is moved so as to move toward the inlet 46 of the rotary shaft 40 along the spiral groove 62 on the outer periphery of the insertion shaft 60. The direction is fixed. Thus, a so-called screw pump is formed by the sleeve 50 fixed to the outer periphery of the lower end portion of the rotary shaft 40 and the insertion shaft 60 fixedly disposed in the casing 11 and provided with the spiral groove 62 on the outer periphery thereof. The

  Next, the operation and effect of the driving apparatus 10 having the above structure will be described.

  That is, when the rotor 23 is rotated by a drive source (not shown), the rotating shaft 40 fixed to the rotor 23 is rotated, and the sleeve 50 is rotated integrally with the rotating shaft 40, while the support frame 25 is interposed via the support member 65. Since the fixed insertion shaft 60 does not rotate, the lubricating oil O that has entered the gap between the inner periphery of the sleeve 50 and the outer periphery of the insertion shaft 60 receives frictional force generated by the speed difference between the sleeve 50 and the insertion shaft 60 and is inserted. It flows along the spiral groove 62 on the outer periphery of the shaft 60 and moves toward the inlet 46 side of the rotary shaft 40 (see FIG. 2).

  As a result, the lubricating oil O stored in the oil reservoir 13 at the bottom of the casing 11 is sucked by the oil supply pump 17 and introduced into the flow path 45 in the rotary shaft 40 from the inlet 46. At this time, since the inner peripheral surface 46a of the inflow port 46 has a tapered shape that gradually increases in diameter toward the lower end of the shaft, the lubricating oil O can be smoothly introduced into the flow path 45.

  Lubricating oil O introduced into the flow path 45 of the rotary shaft 40 rises in the flow path 45 and flows out from the outlet 47 at the upper end of the shaft. The sliding performance in the block 31 is supplied to maintain the lubrication performance.

  In the driving device 10, the inner diameter D2 of the cylindrical wall 52 constituting the sleeve 50 and the outer diameter D3 of the insertion shaft 60 inserted into the sleeve 50 are larger than the outer diameter D1 of the rotary shaft 40. Since it is large, the substantial length of the screw pump (the length of the flow path passing through the spiral groove 62) can be increased, and the lubricating oil that has entered the gap between the inner periphery of the sleeve 50 and the outer periphery of the insertion shaft 60 The centrifugal force acting on O can be increased, and the flow rate of the oil supply pump 17 can be increased. As a result, the flow rate of the lubricating oil O can be ensured even when the rotational speed of the rotary shaft 40 becomes slow due to, for example, an inverter for energy saving, and a necessary amount of lubrication is applied to a predetermined sliding portion of the drive unit 15. Oil O can be supplied.

  Further, a sleeve 50 having a larger inner diameter D2 is fixed to the outer periphery of the lower end of the rotary shaft 40, and an insertion shaft 60 having a spiral groove 62 is inserted into the lower opening of the sleeve 50. Since the screw pump is configured, it is not necessary to provide a large hole in the rotary shaft 40, and the strength thereof can be maintained.

  As described above, the flow rate can be increased by increasing the outer diameter of the insertion shaft constituting the screw pump. The reason will be specifically described with reference to FIG. That is, as shown in FIG. 3, a screw pump including a pipe 1 having a predetermined diameter and a screw shaft 3 disposed in the pipe 1 and provided with a spiral groove on the outer periphery via a spiral protrusion 5. The theoretical flow rate Qth (cm3 / s) is generally represented by the following mathematical formula (1).

  In the above formula (1), D is the outer diameter (cm) of the screw shaft 3, n is the number of revolutions per minute, ε is the width of the helical protrusion 5 (cm), and μ is the length of the screw pump 1 (cm). , P is the pressure difference between the pump inlet and outlet.

  That is, in the calculation formula of the theoretical flow rate Qth of the screw pump, the outer diameter D of the screw shaft 3 is one of the parameters, and is 5/5 of the parameter. This also shows that the flow rate can be increased by increasing the outer diameter of the screw shaft.

  As the rotary shaft 40 rotates, the eccentric shaft 43 rotates, and when the piston 33 reciprocates in the cylinder 31a via the connecting rod 34, it passes through the suction pipe 38 and a valve mechanism (not shown) of the valve plate 35. Thus, the fluid such as the refrigerant gas sucked into the compression chamber 37 is compressed, and the compressed fluid passes through the discharge pipe 39 via a valve mechanism (not shown) and is discharged to the outside of the casing. It has become.

In addition, although the drive device 10 in the said embodiment is applied to the compressor provided with the compression mechanism part 30, it is not limited to this, For example, a turbine generator, a motor, etc. The present invention can be applied to a drive device including a drive unit having a rotating shaft.

  In addition, the compressor in the above embodiment is a so-called reciprocating compressor in which the piston 33 reciprocates. However, for example, a scroll compressor, a rotary compressor, a rotary compressor, or the like may be used as long as it is a type having a mechanism that rotates by a rotating shaft. The present invention can be applied to a piston type compressor, a slide vane type compressor, and the like, and is not particularly limited.

  Further, in the driving device 10 in the above-described embodiment, the outlet 47 is provided at the upper end portion of the rotary shaft 40 and the lubricating oil O is supplied to the compression mechanism portion 30 side. In the middle of the axial direction of 40, a lateral hole-shaped outlet is provided toward the outer diameter side, and lubricating oil is provided between the rotating shaft 40 and the holder 31b of the cylinder block 31 that supports the rotating shaft 40. O may be supplied, and the location where the outflow port is provided can be appropriately set according to the structure of the drive unit of the drive device.

  FIG. 4 shows another embodiment of the drive device according to the present invention. Note that substantially the same parts as those of the above-described embodiment are denoted by the same reference numerals, and description thereof is omitted.

  In the driving device 10a of this embodiment, a spiral groove 62a is formed on the inner periphery of the sleeve 50a as shown in the enlarged explanatory view of the main part in FIG. On the other hand, the insertion shaft 60 a has a cylindrical shape, has no spiral groove on the outer periphery, and is fixed to the support member 65. The insertion shaft 60a is formed with an outer diameter D3 that is larger than the outer diameter D1 of the rotary shaft 40 and smaller than the inner diameter D2 of the cylindrical wall 52 of the sleeve 50a. When the sleeve 50a rotates integrally with the rotary shaft 40, the lubricating oil O flows along the spiral groove 62a on the inner periphery of the sleeve 50a and moves toward the inlet 46 side of the rotary shaft 40. , And supplied to a predetermined sliding portion of the drive unit 15.

  FIG. 5 shows still another embodiment of the drive device according to the present invention. Note that substantially the same parts as those of the above-described embodiment are denoted by the same reference numerals, and description thereof is omitted.

  The driving device 10b of this embodiment is different from the above-described embodiment in that it has two screw pumps.

  As shown in the enlarged explanatory view of the main part of FIG. 5, a recess 63 having a predetermined depth with an upper opening is formed in the center of the insertion shaft 60b. The insertion shaft 60b has a cylindrical shape, and a spiral groove 62 is formed on the outer periphery thereof as in the above embodiment. Further, the insertion shaft 60 b is fixed to the support member 65. Further, the insertion shaft 60b is formed with an outer diameter D3 that is larger than the outer diameter D1 of the rotary shaft 40 and smaller than the inner diameter D2 of the cylindrical wall 52 of the sleeve 50.

  On the other hand, a shaft portion 55 extending downward is screwed to the outer periphery of the lower end portion of the rotary shaft 40 at the center portion of the inner end surface of the sleeve 50, and the shaft portion 55 is disposed on the insertion shaft. A predetermined gap is inserted into the recess 63 of 60b.

  A channel 56 having both upper and lower ends opened is provided at the center of the shaft portion 55, and an upper opening 56 a of the channel 56 communicates with the inlet 46 of the shaft 40. Further, the lower opening portion 56 b of the flow channel 56 has a tapered shape in which the inner peripheral surface gradually increases in diameter toward the lower end of the shaft portion 55.

  In addition, a spiral groove 58 is formed on the outer periphery of the shaft portion 55 via a spiral protrusion 57. This groove 58 forms the “second spiral groove” in the present invention.

  That is, in this embodiment, a first screw pump having a spiral groove 62 is formed between the inner periphery of the sleeve 50 and the outer periphery of the insertion shaft 60b, and the inner periphery of the recess 63 and the outer periphery of the shaft portion 55 of the insertion shaft 60b. Between the two, a second screw pump having a spiral groove 58 is formed.

  Then, when the sleeve 50 rotates integrally with the rotary shaft 40, the lubricating oil O flows upward from below the sleeve along the spiral groove 62 on the outer periphery of the insertion shaft 60b, and then the lubricating oil O Enters the gap between the inner periphery of the recess 63 of the insertion shaft 60 b and the outer periphery of the shaft portion 55, flows toward the lower portion of the recess 63 along the spiral groove 58 on the outer periphery of the shaft portion 55, and below the shaft portion 55. It flows into the flow path 56 through the opening 56b.

  At this time, the lower opening 56 b of the flow path 56 has a tapered shape in which the inner peripheral surface gradually increases in diameter toward the lower end of the shaft portion 55, so that the lubricating oil O is smoothly introduced into the flow path 56. be able to.

  Further, the lubricating oil O introduced into the flow path 56 of the shaft portion 55 moves to the inlet 46 of the rotary shaft 40 through the upper opening 56 a of the flow path 56, and the flow path 45 of the rotary shaft 40. And is supplied to a predetermined sliding portion of the drive unit 15.

  According to this embodiment, as described above, the first screw pump and the second screw pump are formed, and the lubricating oil O passes through the first screw pump and the second screw pump, and then rotates. Since it is introduced into the 40 inlets 46, the substantial length of the screw pump can be increased, and the flow rate of the oil supply pump 17 can be further increased.

  In the embodiment shown in FIG. 5, spiral grooves are provided on the outer periphery of the insertion shaft 60b and the outer periphery of the shaft portion 55. However, for example, a spiral groove is provided on the inner periphery of the sleeve 50, or the insertion shaft 60b is provided. A spiral groove may be provided on the inner periphery of the recess 63.

DESCRIPTION OF SYMBOLS 1 Pipe 3 Screw shaft 5 Helical protrusion 10, 10a, 10b Drive apparatus 11 Casing 12 Sealed space 13 Oil reservoir part 15 Drive part 17 Oil supply pump 20 Drive mechanism part 21 Stator 22 Spring 22a, 22b Support convex part 23 Rotor 25 Support Frame 26 Shaft fixing hole 27 Shaft support recess 30 Compression mechanism 31 Cylinder block 31a Cylinder 31b Holder 32 Support member 33 Piston 34 Connecting rod 35 Valve plate 36 Cylinder head 37 Compression chamber 38 Suction pipe 39 Discharge pipe 40 Rotating shaft 41 Crank web 43 Eccentricity Shaft 45 Channel 46 Inlet 46a Inner peripheral surface 47 Outlet 50, 50a Sleeve 51 Ceiling plate 51a Shaft insertion hole 52 Cylindrical wall 53 Nut 55 Shaft 56 Channel 56a Upper opening 56b Lower opening 57 Spiral protrusion Part 58 spiral groove 60 60a, 60b inserted shaft 61 helical projections 62,62a helical groove 63 recess 65 supporting members D1 outer diameter D2 inner diameter D3 outer diameter O lubricating oil P Pipe

Claims (5)

A casing,
A drive unit;
An oil reservoir provided at the bottom of the casing;
An oil supply pump that is operated by the power of the drive unit and disposed in the oil reservoir,
In the drive device configured to supply lubricating oil to a predetermined sliding portion of the drive unit by the oil pump,
The drive unit has a rotating shaft,
The rotating shaft extends so that a lower end thereof reaches the oil reservoir, and has a lubricating oil flow path therein.
The flow path includes a lubricant inlet provided at a lower end portion of the rotating shaft, and a outlet provided at a predetermined position of the rotating shaft for supplying the lubricant to the sliding portion. And
The oil supply pump is a cylindrical sleeve that is fixed to the outer periphery of the lower end of the rotating shaft without closing the inlet of the rotating shaft, has an inner diameter larger than the outer diameter of the rotating shaft, and is open at the bottom. When,
The outer diameter of the rotating shaft is larger than the outer diameter of the sleeve and smaller than the inner diameter of the sleeve, is arranged coaxially with the rotating shaft, and is inserted into the sleeve inner periphery from the lower opening of the sleeve, An insertion shaft fixedly supported in the casing,
A driving device, wherein a spiral groove is formed on an inner periphery of the sleeve or an outer periphery of the insertion shaft. The casing forms a sealed space inside, and has a fluid suction part and a discharge part,
The drive unit includes a drive mechanism unit having the rotation shaft, and a compression mechanism unit that is driven by the rotation shaft and compresses the fluid sucked from the suction unit and discharges the fluid from the discharge unit.
The drive device according to claim 1, wherein the drive device is used as a compressor.   The insertion shaft has a concave portion opened upward at the center thereof, and a shaft portion extending toward the lower opening is provided at the central portion of the inner end surface of the sleeve. The inlet of the rotating shaft is in communication with a flow path that opens to the lower end through the center of the shaft, and is inserted into the inner periphery of the recess or the outer periphery of the shaft. The drive device according to claim 1, wherein a spiral groove is formed.   3. The drive device according to claim 1, wherein the flow path of the rotating shaft has an inner diameter that is expanded toward the inlet near the inlet.   The compressor according to claim 3, wherein the flow path of the shaft portion communicating with the inlet of the rotary shaft has an inner diameter that is expanded toward the lower end opening.