JPH0425538Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fluid sealing device for a swing bearing portion of a direct drive device for a mixer drum in a truck mixer.

FIG. 1 shows a side view of an example of a truck mixer equipped with the device of the present invention. In the figure, 1 indicates a truck body, and 2 indicates a mixer drum mounted on the vehicle body 1. This mixer drum 2
2 is installed on the vehicle body 1 and at the rear of the vehicle body 1.
It is supported by a book roller 3 and a direct drive support device 8 provided inside a speed reducer 5 fixed to a support frame 4 fixed near the front of the vehicle body 1. Further, this reducer 5 is integrally provided with a hydraulic motor 6, and the power is transmitted from the reduction gear mechanism in the reducer 5 to the mixer drum 2 via a direct drive support device 8 fixed to the reducer 5. The mixer drum 2 can be directly transmitted to the mixer drum 2 to drive the mixer drum 2.

Next, FIG. 2 is a sectional view showing the reduction gear mechanism 7 disposed inside the reduction gear 5, the direct drive support device 8 connected thereto, and the sealing mechanism thereof according to the present invention. It is something. As shown in the figure, the power from the hydraulic motor 6 fixed to the housing 9 of the reducer 5 is transmitted to the first shaft 11 of the reduction gear mechanism 7 built in the reducer 5, and from this first shaft 11. , the gear is transmitted to the second shaft 13 through the meshing of the small gear 12 attached to the small gear 12 and the large gear 14 attached to the second shaft 13 parallel to the first shaft 11. A small gear 15 attached to two shafts 13 and a third shaft 16 parallel to the second shaft 13
Furthermore, a large sun gear 18 attached to the third shaft 16 is connected to the housing of the direct-coupled drive support device 8 in a second reduction stage that transmits the transmission to the third shaft 16 through meshing with the large gear 17 attached to the housing of the direct drive support device 8. A cantilevered pin shaft 22 is rotatably fitted into a carrier 21 which is integrally attached to one end of a drive shaft 20 which is rotatably supported concentrically with the third shaft 16 on a drive shaft 19 . The signal is transmitted to the third reduction stage, which is a planetary gear, which transmits the signal to the drive shaft 20 through meshing with the planetary gear that meshes with the internal gear 24 fixed to the housing 9, and is output.

A spherical spline portion 25 having a rotation center b on the center line a of the drive shaft 20 is provided at the tip of the drive shaft 20, and is fixed to the support structure at the front end of the mixer drum 2. The load of the mixer drum 2 is transferred via the flange part 32 to the outer peripheral part of the rotary shaft 30 and the housing 19 of the direct-coupled drive support device 8. The self-aligning roller bearing 2 is provided so as to have the same rotation center b as the spherical spline part 25 between the self-aligning roller bearing 2 and the inner peripheral part of the spherical spline part 25.
6, the rotational axis of the output shaft 30, which oscillates as the mixer drum vibrates, is always on the rotation center b, so that the engagement between the spherical spline 25 and the spline portion 31 is improved. Since the position is always maintained at a constant radius from the rotation center b, a natural engagement is maintained and stable power transmission is achieved.

As described above, a fluid sealing member is installed between the rotating shaft 30 that oscillates and the housing 19 of the self-aligning roller bearing 26 so as to cover the self-aligning roller bearing 26, but this member has conventionally been installed as shown in FIG. As shown in
114811)), the seal carrier 33 is fixed to the housing 19 and the seal race 34 is fixed to the rotating shaft 30. 33 and the sliding surface 35 of the seal race 34 is the rotation center b of the self-aligning roller bearing.
(Fig. 2) is made to coincide with the spherical surface centered at the center.
In this way, since the rotating shaft 30 and the self-aligning roller bearing 26 swing around the rotation center b of the self-aligning roller bearing 26 as a fulcrum, the seal race 34 that is integral with the rotating shaft 30 also has the same fulcrum as the center b of the seal carrier 33. In addition to swinging on a spherical surface, a circumferential groove 36 is provided on the sliding spherical surface of the seal carrier 33.
An O-ring 35 is inserted into the ball 6 to prevent lubricating oil from leaking through the gap between the sliding spherical surfaces.

However, the rotary shaft 30, which is integrally connected to the mixer drum 2, receives an axial pressing force from the mixer drum 2, and the magnitude of this pressure varies greatly between when the drum is empty and when it is filled with concrete material. In this state, the rotating shaft 30 receives a large pressing force from the direction of the drum, and moves slightly from side to side in the drawing. As a result, the seal carrier 33 and the seal race 34 were slightly misaligned in the axial direction, resulting in a gap between the sliding spherical surfaces and leakage of lubricating oil.

In order to eliminate this drawback, the present invention has a seal carrier 39 fixed to the housing 19 and a seal race 34 fixed to the rotating shaft 30, as shown in FIG.
between the inner circumferential surface 39 ₁ of the cylindrical seal carrier 39 and the spherical sliding surface 34 ₁ that provides the same rocking center as the bearing portion 26 of the seal race 34 as a self-aligning roller bearing. An intermediate seal carrier 42 is provided which receives a pressing force to the left in the figure by a spring 40 which abuts against the seal carrier 39 so as to slide in the axial direction in contact with the seal carrier 39 via a ring. This intermediate seal carrier 42 is connected to the housing 1
A groove is provided between the outer circumferential sliding surface 42 ₁ of the intermediate seal carrier 42 and the inner circumferential sliding surface 39 ₁ of the seal carrier 39 . A groove 45 is formed between the spherical sliding surface 34 1 of the seal race 34 and the spherical sliding surface 42 ₁ of the intermediate seal carrier 42 in contact with the spherical sliding surface 34 ₁ of the seal race 34 . Fluid leakage is sealed by an O-ring 46 fitted into the holder. In order to keep the crushing margin of the O-ring 46 in close contact with the spherical sliding surface 41 almost constant, the intermediate seal carrier 42
A plurality of holes 4 axially opening on the right side in the drawing
0 ₁ is drilled, and the spring 40 is inserted into this hole 40 ₁ .
One end of this spring 40 is connected to the seal carrier 3.
9 to constantly apply a pressing force to the O-ring 46 via the intermediate seal carrier 42. With this configuration of the seal, the intermediate seal carrier 42 receives a leftward pressing force from the spring 40.
It is designed to move according to the leftward shift of the seal race 34, and is in contact with the spherical sliding surface 41.
The ring 46 is kept in close contact with the ring 46, which has the effect of preventing leakage of lubricating oil from this gap.

As described above, the present invention provides a configuration of a fluid seal for an oscillating rotor from the housing 19 to the seal carrier 3.
Since the intermediate seal carrier 42 is provided which is pressed by the spring 40 via the intermediate seal carrier 42, the O-ring 46 fitted into the groove 45 of the intermediate seal carrier 42 and the sliding surface ₃₄₁ on the outer periphery of the seal race 34 are always in close contact with each other. This feature prevents lubricating oil from leaking from this gap.

[Brief explanation of the drawing]

Fig. 1 is a schematic front view of a track mixer equipped with the device of the present invention, Fig. 2 is a longitudinal sectional view showing one embodiment of the device of the present invention, and Fig. 3 is a portion of the seal structure of the direct-coupled drive support device of the present invention. The cross-sectional view, FIG. 4, also shows a partial cross-sectional view of a conventional seal arrangement. 8...Directly coupled drive support device, 19...Housing, 26...Self-aligning roller bearing, 30...Rotating shaft, 34...Seal race, 34 ₁ ...Sliding surface,
39...Seal carrier, 39 ₁ ...Sliding surface, 4
0... Spring, 40 ₁ ... Hole, 41... Spherical sliding surface,
42...Intermediate seal carrier, 42 ₁ , 42 ₂ ...
sliding surface.

Claims (1)

[Scope of utility model registration request] A rotating shaft 3 fixed integrally with a swinging rotating body 32
0 on the housing 19 in a swingable manner, the housing 19 and the rotating shaft 30
A seal carrier 39, which is a cylindrical cover having a sliding surface ₃₉₁ on the inner periphery, is fixed to the housing 19 so as to cover the outside of the bearing part 26, and a rotary shaft 30 is in contact with the outside of the bearing part 26. The outer circumferential surface of the seal carrier 39 is fixed to the inner circumferential sliding surface 39 ₁ of the seal carrier 39 between the seal race 34 and the seal race 34 which has a spherical sliding surface 34 ₁ having the same center of rotation as the bearing 26 on the outer periphery. and the inner circumferential surface of the seal race 34 on the outer circumferential sliding surface ₃₄₁ of the O-ring 4, respectively.
A plurality of holes 40 1 having sliding surfaces 42 ₁ and 42 ₂ that are in contact with each other through 4 and 46 and opening outward in the axial direction are bored, and the spring 40 is fitted into the hole 40 ₁ , and the spring 40 is inserted into the hole 40 ₁ . One end of 40 is connected to the seal carrier 3
9 and in close contact with the sliding surface 34 ₁ ,
O-ring 4 inserted into the groove 45 of the sliding surface 42 ₂
Bearing part 2 so that the crushing allowance of 6 is almost constant.
6. A fluid sealing device for an oscillating rotating body, characterized in that an intermediate seal carrier 42 is provided to apply an axial pressing force to the oscillator 6.