JPH0658186U - Planetary gear pump - Google Patents

Abstract

(57) [Abstract] [Purpose] The conditions for supplying viscous fluid to the inlet side space of the meshing part where the sun gear and the planetary gear mesh are uniform, and a large number of ports are formed without causing seizure. Transfer the fluid in a uniform flow. A sun gear 26 and a planetary gear 27 meshing with the sun gear 26 are provided in a casing 25 sandwiched by two side plates 23, 24, and a conical trapezoidal guide surface is provided at one end 44 of a drive shaft 30. 47 to form an input port 48
And the radial flow paths 53 having a uniform flow path length are formed to make the supply conditions of the viscous fluid uniform.
Lubrication is achieved by forming concave grooves 56 to 59 extending in the radial direction on the inner surfaces 46 and 54 of the No. 4 and connecting the inlet side space and the outlet side space.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a planetary gear pump for quantitatively transferring viscous fluid such as ink and paint to a plurality of flow paths.

[0002]

[Prior art]

 FIG. 6 is a sectional view showing a typical prior art planetary gear pump 1, and FIG. 7 is a left side view of the planetary gear pump 1. The partition wall 3 arranged in the center is sandwiched by two casings 4, 5, and each casing 4, 5 is sandwiched by two side plates 6, 7. Two sun gears 9 and 10 are fixed to a drive shaft 8 which is rotationally driven around a rotation axis, and for example, four sun gears 11a to 11d are provided at equal intervals in the circumferential direction on each sun gear 9 and 10, respectively. 13a to 13d are arranged. The planetary gears 11a, 13a; 11b, 13b; 11c, 13c; 11d, 13d forming a pair on the same axis are connected to the shafts 14a to 14d, and the sun gears 9, 10 are rotationally driven in the arrow A1 direction. As a result, they are driven to rotate in the direction of arrow A2. Inflow holes 18a to 18d in the inlet space formed on the upstream side of the rotation directions A1 and A2 with respect to the meshing portions 15a to 15d where the sun gears 9 and 10 mesh with the planetary gears 11a to 11d; 13a to 13d; 19a to 19d communicate with each other, and a viscous fluid such as ink or paint is supplied. Outflow holes 16a to 16d; 17a to 17d communicate with the outlet space formed on the downstream side of the rotation directions A1 and A2 with respect to the meshing portions 15a to 15d, and the planetary gears 11a to 11d; The viscous fluid extruded by the meshing of the teeth of the and the teeth of the sun gears 9 and 10 is discharged. Such prior art is disclosed in, for example, Japanese Patent Publication No. 44-893 (Japanese Patent Application No. 40-60636).

[0003]

[Problems to be solved by the device]

 In such a prior art, the viscous fluid is applied to the sun gear 9 and the planet gears 11a to 11d provided near the one side plate 6 and the sun gear 10 and the planet gears 13a to 13d provided near the other side plate 7. Since the inflow holes 18a to 18d: 19a to 19d for supplying each have different path lengths, even if viscous fluid is supplied at the same pressure, the pressure difference in the inlet space due to the difference in flow path resistance. Therefore, there is a problem that the first-stage planetary gears 11a to 11d and the second-stage planetary gears 13a to 13d have different viscous fluid supply conditions. In order to make the supply conditions of such viscous fluid the same, the diameter of the sun gear is made large and all the planetary gears 11a to 11d; 13a to 13d are meshed, and they are extended radially from the rotation axis of the sun gear. Although it is easily conceivable to form an inflow hole that communicates with each inlet space formed between the sun gear and the planetary gears, doing so increases the peripheral speed at the peripheral edge of the sun gear, thus providing sufficient lubrication. The problem arises in that

Therefore, an object of the present invention is to supply a viscous fluid to each inlet space formed between a sun gear and each planetary gear under the same supply condition without causing insufficient lubrication. It is to provide a planetary gear pump according to the above.

[0005]

[Means for Solving the Problems]

 According to the present invention, a pump chamber is formed in a casing sandwiched by two side plates, and a sun gear fixed to a drive shaft that is rotationally driven in a predetermined rotation direction in the pump chamber and a circumferential direction around the sun gear. A plurality of planetary gears that are arranged at equal intervals in the sun gear and that are driven by meshing with the sun gear are housed.The sun gear and each planetary gear are located upstream of the meshing portion of the sun gear and each planetary gear in the rotation direction. The viscous fluid supplied to the inlet space formed between the gears is stored in the tooth space of each planetary gear and transferred to the outlet space formed downstream of the meshing part in the rotational direction. In the planetary gear pump to be extruded, a lubricating groove is formed in each of the inner surfaces of the two side plates facing the pump chamber in the radial direction so as to connect the inlet space and the outlet space. The drive shaft is inserted into A shaft hole is formed in each shaft, and one end of the drive shaft arranged in one shaft hole is retracted closer to the inner surface than the outer surface of the side plate in which the shaft hole is formed to form an input port. , A tapered guide surface is formed at one end of the drive shaft facing the input port, and one side plate on which the input port is formed is provided with a plurality of communication ports that connect the input port and each of the input side spaces. The planetary gear pump is characterized in that the flow passages are formed radially.

[0006]

[Action]

 According to the present invention, the pump chamber formed in the casing is provided with a sun gear and a plurality of planetary gears meshing with the sun gear, and the sun gear has a shaft formed on each side plate. It is inserted into the hole and pivotally supported. The tip portion of the shaft inserted into the shaft hole of one side plate is retracted toward the inner surface rather than the outer surface of the side plate, and is formed in a taper shape to form a single input port. An inlet space is formed on the upstream side in the rotational direction with respect to the meshing portion where the sun gear and each planetary gear mesh with each other, and each inlet space and the input port communicate with each other through a plurality of flow paths. As a result, the inflow paths of the viscous fluid to the inlet spaces have the same length, and therefore the supply conditions of the viscous fluid supplied to the inlet spaces are the same. In addition, on the inner surfaces of the side plates facing each other across the pump chamber, there is formed a groove for lubrication that communicates a high-pressure outlet space and a low-pressure inlet space in the radial direction. The high-pressure viscous liquid extruded into the side space is guided to the entrance side space side through the concave groove, whereby the inner surface of each side wall and the sun gear can be lubricated.

[0007]

【Example】

 1 is an enlarged sectional view showing a planetary gear pump 21 according to an embodiment of the present invention, and FIG. 2 is a front view of the planetary gear pump 21 as viewed from the left side of FIG. A casing 25 sandwiched by the two side plates 23, 24 is provided with a pump chamber 28 in which a sun gear 26 and a plurality of planet gears 27 (8 in this embodiment) are housed. The sun gear 26 is meshed with the sun gear 26 at a meshing portion 29 at equal intervals.

A drive shaft 30 is fixed to the sun gear 26, and power from a motor (not shown) is decelerated by a speed reducer or the like on the drive shaft 30 and is rotationally driven in the arrow A1 direction at 28 rpm, for example. The drive shaft 30 is inserted into shaft holes 31 and 33 formed in the side plates 23 and 24, and is rotatably supported by metal bearings 34 and 35, respectively. One metal bearing 35 is retained in a liquid-tight state by a holding member 37 via an annular seal member 36, and the holding member 37 is fixed to one side plate 24 by a bolt 38. A shaft hole 39 is also formed in the side plate 24, and shafts 40 that respectively support the planetary gears 27 are press-fitted into the shaft hole 39. Further, the side plates 23, 24 and the casing 25 are positioned with high precision by the lock pin 41 and the bolt 43 screwed to the lock pin 41 and fixed to each other.

The axial one end 44 of the drive shaft 30 inserted into the shaft hole 31 of the other side plate 23 is closer to the inner surface 46 abutting the casing 25 than the outer surface 45 of the side plate 23. The guide port 47 is formed in a retracted shape, and has a tapered truncated cone shape at the tip thereof to form an input port 48. The input port 48 is open at one end of a plurality of (in this embodiment, 8) flow paths 49 radially formed at equal intervals in the circumferential direction, and the other end is connected to the sun gear 26 and the planets. The gear 27 has an opening facing the entrance space 49 formed upstream of the meshing portion 29 of the gear 27 in the rotating direction A1, A2. Further, the output side space 50 formed on the downstream side in the rotation direction A1, A2 of each gear 26, 27 with respect to the meshing portion 29 communicates with the output port 51, respectively. Therefore, the viscous fluid having a viscosity of about 5 to 50 poise supplied to the input port 48 flows into each flow path 53 and is supplied to the inlet space 49 at a uniform pressure. Since the flow paths 53 have the same flow path length, the flow resistance to the viscous fluid in each flow path 53 is the same, and the fluid differential pressure generated by each flow path 53 is extremely small.

FIG. 3 is a sectional view taken along section line III-III in FIG. 1, and FIG. 4 is a sectional view taken along section line IV-IV in FIG. The inner surfaces 46, 54 of the side plates 23, 24 facing each other are arranged radially outward from the shaft holes 31, 33 with respect to the central axis 55 in the radial direction across the inlet space 49 and the outlet space 50. Recessed grooves 56, 57; 58, 59 are formed. These concave grooves 56 to 59 are U-shaped as shown in an enlarged manner in FIG. 5, and the width B thereof is selected to be, for example, about 0.5 mm. By forming such grooves 56 to 59, the viscous fluid passes from the high pressure outlet space 50 between the shaft holes 31 and 33 and the outer peripheral surface of the drive shaft 30 to the low pressure inlet side. Guided into space 49, it is possible to achieve lubrication of drive shaft 30 and sun gear 26. In particular, by providing these recessed grooves 56 to 59, the diameter of the sun gear 26 is increased by a one-stage gear pump to increase the number of planetary gears meshing with the sun gear 26 and increase the number of ports. A planetary gear pump can be realized. In this way, even if the diameter becomes large, it is possible to make the supply conditions of the viscous fluid to the inlet space 49 uniform and to obtain a large number of flows, and to retain viscous fluid such as ink or paint that easily deteriorates or discolors. The number of points can be reduced as much as possible, and the viscous fluid can be smoothly pumped in a fixed amount.

[0011]

[Effect of device]

 As described above, according to the present invention, a tapered guide surface is formed at one end of the shaft facing the input port, and the viscous fluid guided radially outward by the guide surface is formed in a plurality of radial directions. It is possible to obtain uniform flow of viscous fluid from a plurality of outlet spaces because it can be guided to the flow path of the inlet and to be supplied uniformly to the inlet space.In addition, a concave groove can be formed on the inner surface of each side plate. Therefore, reliable lubrication can be achieved regardless of the diameter of the sun gear.

[Brief description of drawings]

FIG. 1 is an enlarged cross-sectional view showing a planetary gear pump 21 according to an embodiment of the present invention.

2 is a left side view of the planetary gear pump 21. FIG.

FIG. 3 is a sectional view taken along section line III-III in FIG.

FIG. 4 is a sectional view taken along the section line IV-IV in FIG.

5 is a sectional view taken along the section line VV in FIG.

FIG. 6 is a cross-sectional view showing a typical prior art planetary gear pump 1.

7 is a left side view of the planetary gear pump 1 shown in FIG.

[Explanation of symbols]

 21 Planetary Gear Pump 23, 24 Side Plate 25 Casing 26 Sun Gear 27 Planetary Gear 28 Pump Chamber 29 Engagement Part 30 Drive Shaft 31, 33 Shaft Hole 44 One End of Drive Shaft 45 45 Outer Surface of Side Plate 23 46, 54 Inner Surface 48 Input port 49 Input side space 50 Output side space 51 Output side port 53 Flow path 56, 57, 58, 59 Recessed groove

Claims (1)

[Scope of utility model registration request] 1. A pump chamber is formed in a casing sandwiched by two side plates, and a sun gear fixed to a drive shaft that is rotationally driven in a predetermined rotation direction in the pump chamber, and a circumference around the sun gear. Arranged at equal intervals, a plurality of planetary gears that mesh with and follow the sun gear are housed, and the sun gears and The viscous fluid supplied to the inlet side space formed between the planetary gears is stored in the tooth space of each planetary gear and transferred to the outlet side space formed on the downstream side in the rotational direction of the meshing portion. In the planetary gear pump that pushes out, a lubricating groove that communicates the inlet space and the outlet space is formed in each of the inner surfaces of the two side plates facing the pump chamber in the radial direction, and the two side plates are provided. Is the shaft through which the drive shaft is inserted. And one end of the drive shaft disposed in one of the shaft holes is retracted closer to the inner surface than the outer surface of the side plate in which the shaft hole is formed to form an input port. A tapered guide surface is formed at one end of the drive shaft facing the input port, and one side plate on which the input port is formed is provided with a plurality of flow paths that communicate the input port with each of the inlet spaces. A planetary gear pump, characterized in that it is formed radially.