JP3032359B2 - Mission equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mission device suitable for use in an axial piston type hydraulic pump as an oblique shaft type pump used for civil engineering, construction equipment and other general machinery.

[0002]

2. Description of the Related Art As a conventional mission device of this kind,
For example, there are Japanese Patent Application No. 2-168339 and FIGS. 6 to 9. 6 to 9 show an axial piston type hydraulic pump. The casing 1 of the hydraulic pump comprises a substantially cylindrical casing body 1A and a head casing 1B closing one end thereof. 2 is the casing body 1A
The rotary shaft 2 is rotatably supported via a bearing 3 and is rotatably supported by an engine (not shown). A disk-shaped drive disk 2 </ b> A is integrally formed on the tip end side of the rotating shaft 2.
Reference numeral 4 denotes a cylinder block which is located in the casing body 1A and rotates together with the rotary shaft 2, and a plurality of cylinders 5 are bored in the cylinder block 4 in the axial direction. A piston 6 is provided in each cylinder 5 so as to be able to reciprocate, and a spherical portion 7A of a connecting rod 7 attached to a tip of the piston 6 is swingably supported by the drive disk 2A.

Reference numeral 8 denotes a valve plate whose one end surface is in sliding contact with the cylinder block 4. The valve plate 8 has supply / discharge ports 8 B, which can communicate with each cylinder 5 by rotation of the cylinder block 4.
8C is provided. These supply / discharge ports 8B, 8C
Communicates with the supply / discharge passages 10 and 11 of the head casing 1B. One end of the center shaft 12 is fitted into a through hole 8A formed in the center of the valve plate 8,
A spherical portion 12A formed at the other end of the center shaft 12 is swingably supported by the drive disk 2A. The cylinder block 4 is supported between the drive disk 2A and the valve plate 8 by the center shaft 12.

[0004] Reference numeral 1C denotes a transmission casing, in which a drive gear 13 fitted to the spline portion 2B of the rotary shaft 2 is provided. A driven gear 14 having a speed ratio of 1 to 1 is meshed with the drive gear 13, and a shaft 15 supported via a bearing 50 on a boss 30 of the transmission casing 1 </ b> C is provided at the center of the driven gear 14. It has been inserted. A spline portion 15A provided on an outer peripheral surface of the shaft 15 meshes with a spline formed in a shaft hole of the driven gear 14, and
A spline shaft 16A, which is an input shaft of the second pump 16, meshes with a spline portion 15B provided in the shaft hole. Thus, when the driven gear 14 rotates, the rotation is transmitted to the spline shaft 16A of the second pump 16 via the shaft 15, and the second pump 16 is driven. Here, an appropriate amount of transmission oil is sealed in the transmission casing 1C, so that the drive gear 13 and the driven gear 14 can rotate smoothly.

[0005] A seal member 17 is provided on the rotating shaft 2.
18 is provided to prevent transmission oil in the transmission casing 1C from leaking to the outside. Further, reference numeral 19 in FIG. 8 denotes a breather provided in the transmission casing 1C.
3. When the driven gear 14 rotates to agitate the mission oil, the internal pressure in the transmission casing 1C is prevented from rising. Reference numeral 19a in FIG. 9 indicates a mounting screw portion of the breather 19.

As shown in FIGS. 8 and 9, a portion of the boss portion 30 of the transmission casing 1C includes transmission oil at a portion where the spline shaft 16A of the second pump 16 meshes with the spline portion 15B of the shaft 15. Notch 31 for guiding the air flow. That is, the meshing portion between the spline shaft 16A and the spline portion 15B is
The boss portion 30 is located in the boss portion space SP separated from the space in the transmission casing 1C by the bearing 50 provided in the boss portion 30, and it is difficult for the transmission oil to enter the boss portion space SP. Therefore, a notch 31 is formed in the boss portion 30 so that the transmission oil scattered by the rotation of the driven gear 14 is guided through the notch 31 into the boss portion space SP, that is, the meshing portion between the spline shaft 16A and the spline portion 15A. I have to.

[0007]

However, if the notch 31 is simply formed in the boss portion 30 as described above,
Mission oil adhering to the inner wall of the transmission casing 1C does not sufficiently flow into the boss space SP from the notch 31. In particular, at the time of low-speed drive of the pump, the amount of the mission oil stirred by the driven gear 14 is not sufficient, and the spline shaft 16A passes through the notch 31.
Insufficient amount of oil is guided to the meshing portion between the shaft and the shuff spline portion 15A, and wear or seizure may occur due to lack of oil. In addition, at the time of high rotation of the pump, the amount of oil scattered when the mission oil is stirred increases, and the oil scatters near the breather 19,
There is a possibility that the transmission oil may squirt from the breather 19.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a transmission device which improves the lubricity of a spline portion and prevents oil from blowing out from a breather portion.

[0009]

The present invention will be described with reference to FIGS. 1 and 6 showing one embodiment. The present invention provides a transmission casing 1C in which transmission oil is sealed, and a transmission casing 1C provided in the transmission casing 1C. A drive gear 13 driven by an external input, and a driven gear 14 supported by a boss 30 provided in the transmission casing 1C via a bearing 20 and driven by the drive gear 13
And a driving device 16 spline-coupled to the shaft portion 15 of the driven gear 14 and provided outside the transmission casing 1C.
And a breather portion 19 for adjusting the internal pressure of the transmission casing 1C. The driving device 16 and the driven gear 14 are spline-coupled to each other in a boss space SP sandwiched between the bearing 20 and the driving device 16, and the boss space SP The present invention is applied to a transmission device in which a notch 31 for communicating with a space in the transmission casing 1C is provided in the boss 30. And
First and second projections 2 that connect the inner wall of the transmission casing 1C and both ends of the notch 31 and guide the transmission oil scattered by the driven gear 14 to the boss space SP.
0 and 21 are provided, and the second protrusion is arranged at a position where the scattered mission oil is prevented from reaching the breather portion 19, thereby solving the above problem. According to the second aspect of the present invention, the first projection 20 is formed by cutting out the transmission oil adhered to the inner wall of the transmission casing 1C.
The second protrusion 21 is formed so as to be inclined so as to flow into the other end of the notch 31 due to collision of oil droplets of the mission oil which are agitated and scattered in the rotation direction of the driven gear 14 and collide. It is provided.

[0010]

The transmission oil scattered by the driven gear 14 is supplied to the boss space SP by the first and second projections 20 and 21.
Is led to. In particular, according to the second aspect of the invention, the transmission oil adhering to the inner wall of the transmission casing 1C is the first transmission oil.
Of the mission oil, which is agitated in the rotation direction of the driven gear 14 and scatters, collides with the second projection 21 and flows into the other end of the notch 31. As a result, a sufficient amount of transmission oil is guided to the spline connection portion between the driving device 16 and the driven gear 14, and friction and seizure can be prevented. According to the third aspect of the present invention, the oil droplets scattered from the driven gear 14 are blocked by the second projection 21 and do not reach the breather portion 19 of the transmission casing 1C. Is prevented.

In the means and means for solving the above problems which explain the constitution of the present invention, the drawings of the embodiments are used to make the present invention easy to understand. However, the present invention is not limited to this.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS. Note that the same components as those described in the related art are denoted by the same reference numerals, and detailed description thereof will be omitted. FIG. 1 is a partial perspective view showing the inside of a transmission casing 1C of a transmission device according to the present invention, and FIG.
FIG. 3A is a plan view of FIG. 6, and FIGS. 3A and 3B are a plan view of FIG. 1 and a cross-sectional view taken along line bb of FIG. The above-mentioned transmission casing 1C is provided with an outwardly bulging portion 22 as shown in FIG. 2, and along an inclined edge 23 of the bulging portion 22, an inner wall of the transmission casing 1C and a boss portion 30 are formed. A stepped oil passage 20 connecting the one end 31 </ b> A of the notch 31 is provided on the inner wall side of the bulging portion 22.
On the other hand, along the other edge 24 of the bulging portion 22, the L-shaped oil passage 21 that connects the inner wall of the transmission casing 1C and the other end 31B of the notch 31 and is ribbed inside the transmission casing 1C is formed. Is formed.

The stepped oil passage 20 and the L-shaped oil passage 21 collect mission oil agitated and scattered by the driven gear 14 in a notch 31 and guide the mission oil to the boss space SP. The operation will be described with reference to FIG. When the rotation shaft 2 of FIG. 6 rotates and the drive gear 13 rotates, the driven gear 14 meshing with the drive gear 13 rotates in the direction B of FIG. 4, and at this time, the transmission oil in the transmission casing 1C is removed. It is agitated and scattered by the driven gear 14.
Part of the scattered mission oil adheres to the inner wall of the mission casing 1C, and particularly, the mission oil that adheres to the inner wall 22A of the bulging portion 22 drops downward along the inner wall 22A and is a stepped oil passage having a slope shape. 20, the oil travels along the stepped oil passage 20, reaches one end 31A of the notch 31, and then flows into the boss space SP. On the other hand, the mission oil scattered in the rotation direction of the driven gear 14 collides with the L-shaped oil passage 21 and then drops along the L-shaped oil passage 21 to drop the other end 31B of the notch 31.
And flows into the boss space SP from here.

As described above, the transmission oil is guided to the boss space SP through the two oil passages, the stepped oil passage 20 and the L-shaped oil passage 21, so that a sufficient amount of oil can be supplied even when the pump is driven at a low speed. The transmission oil is guided through the notch 31 to the boss space SP, that is, the meshing portion between the spline shaft 16A and the spline portion 15A, thereby preventing wear and seizure. Further, when the pump is rotating at high speed, the amount of oil scattered when the transmission oil is stirred increases, but most of the transmission oil scattered in the rotation direction of the driven gear 14 collides with the L-shaped oil passage 21 and reaches the breather 19. Therefore, the emission of the mission oil from the breather 19 is suppressed.

In the configuration of the above embodiment, the second pump 16 corresponds to the drive unit, the stepped oil passage 20 corresponds to the first protrusion,
Each of the U-shaped oil passages 21 forms a second protrusion.

As shown in FIG. 5, projections 120 and 121 are provided to connect the inner wall of the casing 1C and both ends 31A and 31B of the notch 31 without forming a bulging portion in the transmission casing 1C. These protrusions 12
Even if the mission oil scattered by the driven gear 14 via the gears 0 and 121 is guided to the boss space SP, the same effect as described above can be obtained.

In the above description, the fixed displacement type oblique shaft type hydraulic pump has been described. However, the present invention is also applied to a transmission device used for a variable displacement type swash plate type hydraulic pump for tilting a cylinder block to a valve plate. Can be applied. In addition, the present invention can be similarly applied to various mission devices used other than the pump.

[0018]

As described above, according to the present invention, the first and second projections for guiding the mission oil scattered by the driven gear into the boss space are provided. It is possible to guide a sufficient amount of mission oil to the spline joint, improve the lubrication performance of the spline joint, and prevent friction and seizure. Further, since the scattered transmission oil is prevented from reaching the breather portion of the transmission casing by being blocked by the second projection, it is possible to prevent the transmission of the transmission oil from the breather. In particular, according to the invention of claim 2, the transmission oil adhering to the inner wall of the transmission casing is guided to the notch of the boss portion by the first projection, and the transmission oil which is stirred and scattered in the rotation direction of the driven gear. Since the droplet is guided to the notch by the second protrusion, the lubrication performance of the spline connection portion can be further improved.

[Brief description of the drawings]

FIG. 1 is a perspective view of a main part showing an embodiment of a mission device according to the present invention.

FIG. 2 is a front view of the transmission casing as viewed from a direction A in FIG. 6;

3A and 3B show a main part of a transmission casing, wherein FIG. 3A is a diagram viewed from the inside, and FIG. 3B is a cross-sectional view taken along line bb.

FIG. 4 is an explanatory diagram illustrating an operation.

FIG. 5 is a perspective view of a main part showing another embodiment.

FIG. 6 is a plan sectional view of an axial piston type hydraulic pump having a transmission device.

FIG. 7 is a side sectional view of the pump.

FIG. 8 is a view of a conventional transmission device as viewed from a direction A in FIG. 6;

FIG. 9 is a perspective view of a main part of a conventional transmission device.

[Explanation of symbols]

 Reference Signs List 1C Transmission casing 13 Drive gear 14 Follower gear 15 Shaft 15B Spline portion 16 Second pump 16A Spline shaft 19 Breather 20 Stepped oil passage 21 L-shaped oil passage 22 Swelling portion 30 Boss portion 31 Notch 31A, 31B Notch end Part 50 Bearing SP Boss part space

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Shigetaka Nakamura 650, Kandamachi, Tsuchiura-shi, Ibaraki Hitachi Construction Machinery Co., Ltd. (72) Inventor Yukihiro Motozawa 650, Kandamachi-cho, Tsuchiura-shi, Ibaraki Hitachi Construction Machinery Co., Ltd. Inside the Tsuchiura Works (56) References JP-A-62-4964 (JP, A) JP-A-57-140964 (JP, A) JP-A 52-69402 (JP, U) JP-A 59-132423 (JP, A) U) Japanese Utility Model Showa 61-38326 (JP, U) Japanese Utility Model Utility Model Hei 1-102561 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F16H 57/00-57/04

Claims (2)

(57) [Claims] 1. A transmission casing in which transmission oil is sealed, a drive gear provided in the transmission casing and driven by an external input, and supported by a boss provided in the transmission casing via a bearing. A driven gear driven by the drive gear; a driving device spline-coupled to a shaft portion of the driven gear; and a driving device provided outside a transmission casing; and a breather unit for adjusting an internal pressure of the transmission casing. In the transmission device in which the driving device and the driven gear are spline-coupled in a boss space sandwiched between the driving device and a cutout provided in the boss portion for communicating the boss space and the space in the transmission casing. Connecting the inner wall of the transmission casing and both ends of the notch, Providing first and second protrusions for guiding mission oil scattered by the driven gear to the boss space, wherein the second protrusion prevents the scattered mission oil from reaching the breather portion. A mission device which is arranged at a position where 2. The first projection is formed so as to be inclined so that mission oil attached to an inner wall of the transmission casing flows into the notch, and the second projection is formed by the driven gear. 2. The transmission device according to claim 1, wherein the transmission device is provided so that oil droplets of the transmission oil which are agitated and scattered in the rotation direction of the notch collide and flow into the other end of the notch.