JP2004125098A - Lubricating part structure of wet multiple disc hydraulic clutch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To supply lubricant uniformly from a lubrication hole formed at a clutch hub to a group of discs, and to prevent the occurrence of seizure by lubrication failure, corotation, and cutting failure. <P>SOLUTION: A lubrication hole 23 that is bored from a lubrication chamber 22 in the clutch hub 4A to a lubrication groove (bottom section) in a spline 1S in the clutch hub 4A, and a waste oil hole that is bored at the gear tooth bottom section of the spline of a clutch housing are formed to form a lubrication path for lubricating between an inner disc and an outer plate. The number of lubrication holes 23 at the side of the clutch piston is made larger than that of the lubrication holes 23 at the side of an end plate formed at the clutch hub 4A. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a lubricating structure of a wet multi-plate hydraulic clutch.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, a wet multi-plate clutch is disclosed, for example, in Patent Document 1. This clutch includes a plurality of lubrication holes each having an oil supply hole formed in a spline tooth bottom surface in a pinion spider (clutch hub) in which a clutch disk is fitted. An oil supply hole is formed. In this pinion spider, the flow of the lubricating oil flowing from the gap on the clutch piston side to the gap on the end plate side occurs at the tooth bottom of the spline, and the amount of lubricating oil supplied between the clutch disks becomes uneven. In order to control this, a lubrication hole is drilled so as to be inclined toward the piston, and the lubrication oil is ejected from the lubrication hole against the flow of the lubrication oil to regulate the flow of the lubrication oil. To prevent the occurrence of seizure, entrainment, and disconnection due to poor lubrication of the clutch.
[0003]
[Patent Document 1]
JP-A-3-103621 (FIG. 1)
[0004]
[Problems to be solved by the invention]
However, when manufacturing a pinion spider, it is necessary to drill a number of lubrication holes in the bottom of the spline obliquely to the axis, which requires special jigs and tools, complicates the manufacturing process, and reduces manufacturing costs. However, there was a problem that the bulk increased. Although the flow of lubricating oil at the bottom of the spline is impeded, the lubricating oil supplied from the inclined oil supply hole and the flowing lubricating oil are mixed, so that the lubricating oil is evenly distributed between the clutch disks. There was a problem that it might not be introduced.
[0005]
The present invention solves the above problems, and can evenly supply lubricating oil to a group of discs from an oil supply hole formed in a clutch hub, thereby preventing seizure, rotation, and disconnection due to poor lubrication. It is an object of the present invention to provide a lubricating portion structure of a wet multi-disc hydraulic clutch which can be prevented from occurring.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, according to the first aspect of the present invention, a plurality of clutch hubs which are externally fitted to the clutch hub via an inner spline are provided between a clutch hub and a clutch housing arranged on an outer peripheral portion of the clutch hub. A disk group consisting of an inner disk and a plurality of outer plates fitted inside the clutch housing via an outer spline and disposed between the inner disks; and a clutch hub which sandwiches the disk group between end plates. A clutch piston capable of connecting and separating the clutch housing and a clutch housing, and a return spring interposed in the disk group and capable of expanding the clutch disk and separating the clutch, comprising: From the oiling chamber formed in the clutch hub, a hole is drilled in the tooth bottom of the shaft side tooth portion of the inner spline of the clutch hub. The lubrication path for supplying oil between the inner disk and the outer plate is formed by the number of lubrication holes provided and the number of oil drain holes drilled in the tooth bottom of the spline of the clutch housing, and the end formed in the clutch hub is formed. The total cross-sectional area of the oil supply hole on the clutch piston side is larger than the total cross-sectional area of the oil supply hole on the plate side.
[0007]
According to the above configuration, the gap formed between the clutch hub and the clutch housing to prevent interference allows the lubricating oil flow from the clutch piston side to the end plate side into the tooth bottom of the spline of the clutch hub. Even if it occurs, the total cross-sectional area of the oil supply hole on the clutch piston side, which is on the upstream side of the lubricating oil flow, is increased to supply more lubricating oil than on the downstream side. Even on the upstream side, sufficient lubricating oil to be supplied between the inner disk and the outer plate is secured, and lubricating oil is evenly supplied between the inner disk and the outer plate in the rotation axis direction of the clutch hub. be able to. Therefore, with a simple configuration that increases or decreases the total cross-sectional area of the oil supply hole, it is possible to prevent the occurrence of seizure, rotation, and cutting failure due to poor lubrication.
[0008]
Further, in the invention according to claim 2, all the oil supply holes are formed in the radial direction of the clutch hub as circular cross sections having the same diameter, and the oil supply hole on the clutch piston side with respect to the total sectional area of the oil supply hole on the end plate side. The total cross-sectional area is in the range of 1.5 to 2.0 times.
[0009]
According to the above configuration, since the oil supply holes are circular and have the same diameter and are formed in the radial direction of the clutch hub, the oil supply holes can be formed easily at low cost and can be manufactured at low cost. By setting the total sectional area of the oil supply hole on the clutch piston side to 1.5 to 2.0 times the end plate side, lubricating oil is supplied between the inner disk and the outer plate to rotate the clutch hub. It can be supplied evenly in the axial direction.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
Here, an embodiment of a wet-type multi-plate hydraulic clutch having a lubricating portion structure according to the present invention will be described with reference to FIGS.
[0011]
As shown in FIGS. 1 and 2, the wet-type multi-plate hydraulic clutches A and B are one of a plurality of built-in transmissions constituting a drive unit of an industrial vehicle such as a wheel loader. The clutch housings 3A and 3B are provided integrally, and the transmission gears 2A and 2B are rotatably supported on both sides of the clutch housings 3A and 3B via bearings. Then, clutch hubs 4A, 4B protrude from the transmission gears 2A, 2B into the clutch housings 3A, 3B, respectively.
[0012]
A plurality of inner disks 6 are externally fitted to the clutch hubs 4A and 4B so as to be slidable only in the direction of the rotational axis O via respective inner splines 1S. As shown in FIG. 8, the inner disk 6 has a hole-side tooth portion 1Sb of the inner spline 1S formed on the inner peripheral portion of the center hole 6a, and lattice-shaped oil grooves 6b formed on the front surface and the back surface, respectively. ing. Further, a plurality of ring-shaped outer plates 7 are slidably fitted in the clutch housings 3A and 3B via the outer splines 2S only in the direction of the rotation axis O. As shown in FIG. 9, the outer plate 7 has a center hole 7a which is loosely fitted in the clutch hub 4A at a predetermined interval, and has a shaft-side tooth portion 2Sa of the outer spline 2S formed in an outer peripheral portion. . A return spring 8 that urges the inner disk 6 in a direction separating the inner disk 6 is interposed on the outer peripheral portion of the outer plate 7, and a disk group D is formed by the inner disk 6, the outer plate 7, and the return spring 8. I have.
[0013]
A ring-shaped end plate 9 is disposed at the distal end of the clutch housings 3A and 3B, and the disk group D and the end plate 9 are pivoted by snap rings 9a fixed to the grooves of the clutch housings 3A and 3B outside the end plate 9. It is locked in the direction of the heart. Further, annular cylinder chambers 11A, 11B are formed at the base ends of the clutch housings 3A, 3B, respectively, and clutch pistons 12A, 12B are respectively disposed in the cylinder chambers 11A, 11B so as to be able to move back and forth. Further, pressure oil holes 13A and 13B are formed in the shaft 1, and communicate with an oil chamber 14 formed on the base end side of the clutch pistons 12A and 12B.
[0014]
Therefore, when hydraulic oil is supplied from the control valve of the transmission (not shown) to the oil chambers 14 and 14 via the pressure oil holes 13A and 13B, the clutch pistons 12A and 12B are protruded, and the inner piston is interposed between the clutch pistons 12A and 12B. 6 and the outer plate 7 are sandwiched, and the frictional force causes the power of the shaft 1 to be transmitted to the transmission gears 2A and 2B via the clutch housings 3A and 3B and the clutch hubs 4A and 4B to be rotationally driven. When the supply of the pressure oil from the control valve is stopped and released, the inner disk 6 is expanded and separated from the outer plate 7 by the return spring 8, and the clutch housings 3A and 3B are separated from the clutch hubs 4A and 4B.
[0015]
The lubricating part structure in the above configuration will be described. The clutches A and B have the same structure except that the number of the inner disk 6 and the number of the outer plates 7 are different due to the difference in the transmission torque. Therefore, only the clutch A is illustrated and the description of the clutch B is omitted.
[0016]
An oil supply chamber 22 to which lubricating oil is supplied from a lubricating oil supply path 21 formed in the shaft 1 is formed in the clutch hub 4A. As shown in FIGS. 2 to 5, the clutch hub 4 </ b> A is provided with a number of oil supply holes 23 that are opened at the tooth bottom of the shaft side tooth portion 1Sa of the inner spline 1 </ b> S. In the clutch housing 3A, a number of oil drain holes 24 are formed in the outer spline 2S from the bottom of the hole side teeth of the outer spline 2S to the outer peripheral surface. As shown by arrows in FIG. A lubricating oil path is configured to allow the lubricating oil supplied to the shaft-side tooth bottom portion 1Sa of the spline 1S to pass between the inner disk 6 and the outer plate 7 and to be discharged from the oil drain hole 24 and circulated.
[0017]
By the way, as shown in FIG. 2, a first gap 25 for preventing contact is formed between the clutch hub 4A and the base of the clutch housing 3A of the shaft 1, and a gap between the clutch hub 4A and the end plate 9 is formed. Also, second gaps 26 for preventing contact are formed respectively. Further, as shown in FIG. 10, a space between the inner spline 1 </ b> S and the cutting edge of the hole-side tooth portion of the inner disk 6 is formed in the oil supply groove 15 at the bottom of the shaft-side tooth portion 1Sa. For this reason, the lubricating oil in the oil supply chamber 22 flows into the oil supply groove 15 of the shaft side tooth portion 1Sa of the inner spline 1S from the first gap 25 and the oil supply hole 23 into the tooth bottom of the shaft side tooth portion 1Sa of the inner spline 1S. The lubricating oil is discharged from the second gap 26 through the oil supply groove 15 and flows into the oil supply groove 15 of the inner spline 1S from the clutch piston 12A side to the end plate 9 side.
[0018]
As a result, when the lubricating oil is uniformly supplied from the lubrication hole 23 to the lubrication groove 15 of the inner spline 1S in the direction of the axis O of the clutch hub 4A, the amount of lubricating oil flowing between the inner disk 6 and the outer plate 7 is reduced. The end plate 9 side is larger than the piston 12A side, and there is a possibility that seizure due to poor lubrication, entrainment, cutting failure, etc. may occur between the inner disk 6 and the outer plate 7 on the clutch piston 12A side.
[0019]
Therefore, in the present invention, as shown in FIG. 7, the total sectional area of the oil supply hole 23 on the clutch piston 12A side is 1.4 from the total sectional area of the oil supply hole 23 on the end plate 9 side formed in the clutch hub 4A. It is formed larger in the range of up to 2.0 times (1.6 times in the figure). This depends on the oil pressure (circulation amount) of the lubricating oil, but if it is less than 1.4 times, the amount of lubricating oil on the clutch piston 12A side is insufficient, and if it exceeds 2.0 times, lubrication on the end plate 9 side. This is due to lack of oil.
[0020]
Further, the oil supply holes 23 are formed to have the same diameter in a circular cross section formed to be equal to or less than the width of the tooth bottom of the shaft side tooth portion 1Sa of the inner spline 1S, and these oil supply holes 23 are formed around the rotation axis O of the clutch hub 4A. It is formed in the radial direction. The number of formed oil supply holes 23, that is, the total cross-sectional area is adjusted in two steps on the end plate 9 side and the clutch piston 12A side according to the formation pitch. The total cross-sectional area may be divided into three or more stages, or may be set in a stepless manner so as to increase sequentially from the end plate 9 side to the clutch piston 12A side.
[0021]
Further, the oil supply hole 23 may be oval or slit-shaped along the length direction of the tooth bottom, but it is difficult to machine, a special machining tool is required, and the strength for transmitting torque to the clutch hub 4A is secured. A circular cross-section is more preferable because of the necessity of performing such operations. Of course, it is needless to say that it is necessary to secure a minimum pitch for securing the strength of the clutch hub 4A even if it is circular.
[0022]
In the above configuration, the lubricating oil is supplied from the lubricating oil supply passage 21 of the shaft 1 to the oil supply chamber 22, and is supplied to the tooth bottom 1Sa of the inner spline 1S from a number of oil supply holes 23 formed in the clutch hub 4A. Then, the lubricating oil passes through the space between each inner disk 6 and the outer plate 7 from the tooth bottom 1Sa to be lubricated, and then is discharged from the oil drain hole 24. On the other hand, a flow from the clutch piston 12A side to the end plate 9 side occurs in the oil supply groove 15 of the inner spline 1S due to the first gap 25 and the second gap 26 of the clutch hub 4A. Although the amount of lubricating oil flowing between the inner disk 6 and the outer plate 7 on the piston 12A side tends to decrease, the number of oil supply holes 23 formed in the inner spline 1S is determined by the total cross-sectional area ratio of the end plate 9 The amount of lubricating oil flowing between the inner disk 6 and the outer plate 7 is approximately equal in the direction of the rotational axis O of the clutch hub 4A because the clutch piston 12A is approximately 1.6 times as large as the clutch piston 12A. It becomes.
[0023]
According to the above configuration, the total cross-sectional area of the oil supply hole 23 formed in the clutch hubs 4A and 4B facing the oil supply groove 15 of the inner spline 1S is approximately 1.6 on the clutch piston 12A side as compared with the end plate 9 side. Therefore, even if the lubricating oil flows in the oil supply groove 15 of the inner spline 1S, the bias of the lubricating oil flowing between the inner disk 6 and the outer plate 7 is eliminated, and the shafts of the clutch hubs 4A and 4B are rotated. The clutch can be uniformly supplied in the direction of the center, and the occurrence of seizure, rotation, and disconnection of the clutch due to poor lubrication can be prevented.
[0024]
【The invention's effect】
As described above, according to the first aspect of the present invention, the gap formed between the clutch hub and the clutch housing allows the lubricating oil supplied from the clutch hub to the spline tooth bottom portion via the lubrication hole, Even if a lubricating oil flow from the clutch piston side to the end plate side occurs in the tooth bottom portion, the total cross-sectional area of the oil supply hole on the clutch piston side was increased to increase the lubricating oil supply amount. Even in the upstream, sufficient lubricating oil is supplied between the inner disk and the outer plate, and the amount of lubricating oil supplied between the inner disk and the outer plate is evenly distributed in the rotation axis direction of the clutch hub. can do. Therefore, with a simple configuration that increases or decreases the total cross-sectional area of the oil supply hole, it is possible to prevent the occurrence of seizure, rotation, and cutting failure due to poor lubrication.
[0025]
According to the second aspect of the present invention, the oil supply hole can be formed inexpensively and easily by forming the oil supply hole in a circular shape having the same diameter in the radial direction of the clutch hub. By setting the total sectional area of the oil supply hole on the clutch piston side to 1.5 to 2.0 times, an appropriate amount of lubricating oil can be evenly supplied between the inner disk and the outer plate. .
[Brief description of the drawings]
FIG. 1 is a half sectional side view showing an embodiment of a wet-type multi-plate hydraulic clutch according to the present invention.
FIG. 2 is an enlarged sectional view of a main part of the clutch.
FIG. 3 is a side view showing an end surface of a clutch hub of the clutch.
FIG. 4 is a sectional view taken along the line AA shown in FIG. 3;
FIG. 5 is a schematic sectional view taken along the line BB shown in FIG. 4;
FIG. 6 is a schematic sectional view taken along the line CC shown in FIG. 4;
FIG. 7 is a partially developed view showing an arrangement of oil supply holes on an inner peripheral surface of the clutch hub.
FIGS. 8A and 8B show an inner disk of the clutch, wherein FIG. 8A is a front view and FIG.
FIGS. 9A and 9B show an outer plate of the clutch, wherein FIG. 9A is a front view and FIG.
FIG. 10 is a partially enlarged sectional view showing an inner spline of the clutch hub.
[Explanation of symbols]
1S, 2S Spline D Disk group O Clutch hub rotation axis A, B Clutch 1 Shaft 2A, 2B Transmission gear 3A, 3B Clutch housing 4A, 4B Clutch hub 6 Inner disk 7 Outer disk 8 Return spring 9 End plate 11A, 11B Cylinder Chambers 12A, 12B Clutch pistons 13A, 13B Pressure oil holes 14 Oil chambers 15 Oil supply grooves 21 Lubricating oil supply paths 22 Oil supply chambers 23 Oil supply holes 24 Drainage holes 25 First gap 26 Second gap

Claims (2)

Between the clutch hub and a clutch housing disposed on the outer peripheral portion of the clutch hub, a plurality of inner disks which are externally fitted to the clutch hub through internal splines, and the inner disks are inserted into the clutch housing through external splines. A disk group consisting of a plurality of outer plates fitted and arranged between inner disks, a clutch piston capable of connecting and separating a clutch hub and a clutch housing by sandwiching the disk group between end plates; and Lubricating portion structure of a wet-type multi-plate hydraulic clutch comprising a return spring interposed in the group and capable of expanding the clutch disk and separating the clutch,
Numerous oil holes drilled from the oil supply chamber formed in the clutch hub to the bottom of the shaft side teeth of the inner spline of the clutch hub, and numerous oil drains drilled to the tooth bottom of the spline of the clutch housing With the holes, form a lubrication path for lubricating between the inner disk and the outer plate,
A lubricating portion structure for a wet-type multi-plate hydraulic clutch, wherein a total cross-sectional area of a lubrication hole on a clutch piston side is formed larger than a total cross-sectional area of a lubrication hole on an end plate formed in the clutch hub. All lubrication holes are formed in the radial direction of the clutch hub as circular sections of the same diameter,
2. The wet multi-unit according to claim 1, wherein the total cross-sectional area of the oil hole on the clutch piston side is 1.5 to 2.0 times the total cross-sectional area of the oil hole on the end plate side. Lubrication part structure of plate hydraulic clutch.

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