JP2005320984A - Sediment intrusion preventing device, and reduction gear equipped with sediment intrusion preventing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prolong service life of a reduction gear equipped with a floating seal. <P>SOLUTION: A sediment intrusion preventing device equipped with a floating seal 22 for preventing intrusion of sediments thereinside from a gap between one casing 3 to be rotated and the other casing 1 to be fixed, is equipped with a first labyrinth seal 26 provided to an opposing part between one casing 3 and the other casing 1, and with a clearance 30 to form a protective wall by sediments which is provided to an opposing part between one casing 3 and the other casing 1 on the outside of the first labyrinth seal 26. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an earth and sand intrusion prevention device used in construction machines such as a hydraulic excavator and a hydraulic crane, and a speed reducer provided with the earth and sand invasion prevention device.

  2. Description of the Related Art Generally, a traveling speed reduction device mounted on a tracked vehicle such as a hydraulic excavator is fixed to a vehicle frame and provided with a stationary casing provided with a traveling motor serving as a rotation source on an inner peripheral side, and the fixed side. The rotating casing is rotatably provided on the outer peripheral side of the casing and is driven by a traveling motor, and a reduction gear mechanism that is provided in the rotating casing and decelerates the rotation of the traveling motor. Yes.

In order to prevent the lubricating oil in the casing from leaking to the outside, this type of speed reducer has a fixed side and a rotary side on the inner side in the vicinity of the facing portion between the fixed side casing and the rotary side casing. It consists of a pair of seal rings arranged to face the inner peripheral side of the casing in the axial direction, and a pair of O-rings sandwiched between the inner peripheral surface of each casing and the outer peripheral surface of each seal ring. Although a floating seal is provided, when a traveling device equipped with this type of speed reducer is used in an environment in which earth and sand are easily attached, the earth and sand are located at the opposing portion between the fixed casing and the rotating casing. It may enter the casing through the formed gap or labyrinth seal, and further reach the floating seal, damage the seal and cause oil leakage.

  In order to prevent the above-described floating seal from being damaged, another member for defining a space for depositing intruding earth and sand is detachably provided on the outer periphery of the facing portion between the stationary casing and the rotating casing. A method has been proposed in which the separate member is periodically removed to discharge the sediment accumulated in the space (see Patent Document 1).

Japanese Utility Model Publication No. 60-43772

In the above-described prior art, since separate members must be prepared, the number of parts and the number of assembling steps increase, and the separate members are periodically removed from the speed reducer to remove the sediment accumulated in the sediment accumulation space. The operation | work of discharging | emitting is required, As a result, the grudge that it becomes impossible to use a traveling apparatus in the meantime also arises.

  In addition, the conventional technique has the above-mentioned problems, but foreign matters such as earth and sand enter the casing basically through a gap formed in the facing portion between the stationary casing and the rotating casing and the labyrinth seal. This is intended to appropriately discharge the invading foreign matter to the outside based on the point that the configuration is unavoidable.

  The present invention was made based on the viewpoint of allowing the invaded earth and sand to exhibit a protective wall function against the invading earth and sand, and thereby, the earth and sand intrusion prevention device capable of extending the life of the floating seal and this An object of the present invention is to provide a speed reducer equipped with an earth and sand intrusion prevention device.

  In order to achieve the above object, the present invention includes a floating seal that suppresses intrusion of earth and sand from a gap between one rotating casing and the other fixed casing. In the earth and sand intrusion prevention device, the first labyrinth seal provided at a facing portion between the one casing and the other casing, and the one casing and the other casing facing each other outside the first labyrinth seal The present invention is a soil and sand intrusion prevention device characterized in that it is provided with a space for creating a protective wall made of soil and sand provided in the section.

  Further, the second aspect of the invention is a pair of seal rings that are arranged to face each other on the inner peripheral side of one rotating casing and the other fixed casing, and whose axial facing surfaces are in sliding contact with each other, In the earth and sand intrusion prevention device provided with a floating seal composed of an O-ring provided between the outer peripheral surface of the seal ring and the inner peripheral surface of each casing, the device is provided at a facing portion between the one casing and the other casing. A first labyrinth seal, a second labyrinth seal, and a space for generating a protective wall made of earth and sand provided between the first labyrinth seal and the second labyrinth seal at the facing portion. It is in the earth and sand invasion prevention device which is the feature.

  Furthermore, the third aspect of the present invention is a pair of seal rings that are arranged to face each other on the inner peripheral side of one rotating casing and the other fixed casing, and whose axial facing surfaces are in sliding contact with each other, In the earth and sand intrusion prevention device provided with a floating seal composed of an O-ring provided between the outer peripheral surface of the seal ring and the inner peripheral surface of each casing, the device is provided at a facing portion between the one casing and the other casing. In addition, the first labyrinth seal, the second labyrinth seal, and the opposing portion between the first labyrinth seal and the second labyrinth seal are provided so as to form a space for generating a protective wall made of earth and sand. An earth and sand intrusion prevention device characterized by comprising a recess.

  According to a fourth aspect of the present invention, there is provided a stationary casing provided with a rotation source, a rotation casing provided so as to be relatively rotatable with respect to the stationary casing and driven by the rotation source, and the rotation side casing. In the reduction gear including a reduction gear mechanism provided in a casing and a floating seal provided between the stationary casing and the rotating casing, the soil intrusion according to any one of the first to third inventions The present invention provides a reduction gear device including a prevention device.

  According to the earth and sand intrusion prevention device of the present invention, the invaded earth and sand can be exhibited as a protective wall function against the earth and sand that subsequently enters, so that damage to the floating seal due to earth and sand can be suppressed. As a result, the life of the floating seal can be extended.

  According to the speed reducer equipped with the earth and sand intrusion prevention device of the present invention, since the invaded earth and sand can exhibit a protective wall function against the earth and sand that subsequently invades, damage to the floating seal due to earth and sand can be suppressed. As a result, the life of the reduction gear can be extended.

Hereinafter, the case where the embodiment of the earth-and-sand penetration prevention device of the present invention and the reduction gear provided with the same is applied to a reduction gear for traveling of a hydraulic excavator will be described with reference to the drawings.
FIG. 1 shows an embodiment of a speed reducer equipped with a soil and sand intrusion prevention device according to the present invention. In FIG. 1, reference numeral 1 denotes a fixed side fixed to a side frame (not shown) of a hydraulic excavator. The fixed casing 1 is fixed to the side frame with a flange 1A at the base end, and a rotating casing 3 to be described later is provided at the distal end.

  Further, an annular projecting portion 1 </ b> B that projects in the axial direction toward the rotating casing 3 is provided on the base end side of the fixed casing 1. A floating seal 22 described later is attached to the inner peripheral surface 1C of the annular projecting portion 1B. A traveling hydraulic motor 2 is integrally provided on the inner peripheral side of the casing 1. A sun gear 11 to be described later is provided on the distal end side of the output shaft 2A of the hydraulic motor 2.

  Reference numeral 3 denotes a rotating casing that is rotatably provided on the outer peripheral side of the casing 1. The rotating casing 3 is filled with lubricating oil for lubricating reduction gear mechanisms 10, 14, 18, which will be described later. ing.

  The rotation-side casing 3 includes a cylindrical drum 4 provided with a flange portion 4A on the base end side thereof, a ring gear 5 provided on the distal end side of the drum 4 and having inner teeth 5A on the inner peripheral side, The ring gear 5 is roughly constituted by another ring gear 6 provided at the end of the ring gear 5 and having an inner tooth on the inner peripheral side 6A, and a lid body 7 that covers the end of the ring gear 6. The casing 3 is rotatably supported on the casing 1 by bearings 8 and 8 provided between the drum 4 and the casing 1.

  Reference numeral 9 denotes a drive wheel 9 provided on the flange portion 4A of the drum 4, and a crawler belt (not shown) of a hydraulic excavator is wound around the drive wheel 9. Furthermore, on the base end side of the drum 4, an annular protrusion 4 </ b> B is provided so as to protrude in an axial direction opposite to the annular protrusion 1 </ b> B of the casing 1. A floating seal 22 described later is attached to the inner peripheral surface 4C of the annular protrusion 4B.

  Reference numeral 10 denotes a first-stage reduction gear mechanism provided in the ring gear 6 of the casing 3. The reduction gear mechanism 10 includes a sun gear 11 integrally formed on the distal end side of the output shaft 2 </ b> A of the hydraulic motor 2, and the sun gear 11. For example, three planetary gears 12 (only one is shown) that mesh with the gear 11 and the inner teeth 6A of the ring gear 6 and revolve around the sun gear 11, and the sun gear 15 to be described later are on the inner peripheral side. It is comprised with the carrier 13 which supports the planetary gear 12 rotatably via the pin 13A in the meshed state.

  Reference numeral 14 denotes a second reduction gear mechanism provided in the ring gear 6 together with the reduction gear mechanism 10. The reduction gear mechanism 14 includes a sun gear 15 that meshes with the carrier 13, and the sun gear 15 and the ring. For example, three planetary gears 16 (only one is shown) meshing with the internal teeth 6A of the gear 6 and the planetary gear 16 can be rotated via a pin 17A in a state where the inner peripheral side meshes with a sun gear 19 described later. And a carrier 17 to be supported.

  Reference numeral 18 denotes a third-stage reduction gear mechanism provided in the ring gear 5 of the casing 3. The reduction gear mechanism 18 includes a sun gear 19 that meshes with the carrier 17, and an inner portion of the sun gear 19 and the ring gear 5. For example, three planetary gears 20 (only one is shown) meshing with the teeth 5A and a carrier 21 fixed to the inner peripheral side of the casing 1 and rotatably supporting the planetary gears 20 via pins 21A. ing.

  Reference numeral 22 denotes a floating seal provided on the inner side of the facing portion between the casing 1 on the fixed side and the casing 3 on the rotation side. This floating seal 22 prevents the lubricating oil contained in the casings 1 and 3 from leaking to the outside. At the same time, earth and sand, rain water and the like are prevented from entering the casings 1 and 3.

  Further, the floating seal 22 includes a pair of seal rings 23 and 23 disposed in the axial direction facing the inner peripheral side of the annular protrusions 1B and 4B of the casings 1 and 3, and outer peripheries of the seal rings 23. It is constituted by a pair of O-rings 24 and 24 sandwiched between the surface 23A and the inner peripheral surfaces 1C and 4C of the casings 1 and 3, respectively.

  Here, in each of the seal rings 23, the radially outer portion of the opposing surfaces facing each other in the axial direction constitutes the sliding contact surfaces 23B and 23B.

  The floating seal 22 applies an axial pressing force to the seal ring 23 by the elastic force of the O-ring 24, thereby causing the sliding contact surfaces 23 </ b> B of the seal rings 23 to slidably contact each other. It is configured to be liquid-tightly sealed.

  Reference numeral 25 denotes an earth and sand intrusion prevention device provided at a facing portion between the stationary casing 1 and the rotating casing 3, and the details thereof will be described with reference to FIG. 2, the same reference numerals as those in FIG. 1 are the same parts. Reference numeral 26 denotes a first labyrinth seal provided at an inner portion of the facing portion between the stationary casing 1 and the rotating casing 3, and the first labyrinth seal 26 is provided at the protruding portion 1 </ b> B of the stationary casing 1. The outer circumferential surface of the annular projection 1D and the inner circumferential surface of the annular projection 4D provided on the projection 4B in the casing 3 on the rotating side are opposed to each other with a gap.

  Reference numeral 27 denotes a second labyrinth seal provided at an outer portion of the facing portion between the stationary casing 1 and the rotating casing 3, and the second labyrinth seal 27 is provided at the protruding portion 1 B of the stationary casing 1. The inner circumferential surface of the annular projection 1E and the outer circumferential surface of the annular projection 4E provided on the projection 4B of the casing 3 on the rotating side are opposed to each other with a gap.

Reference numeral 28 denotes an annular recess formed in the end face of the casing 1 on the fixed side between the first labyrinth seal 26 and the second labyrinth seal 27, and 29 denotes the first labyrinth seal 26 and the second labyrinth seal 27. It is the cyclic | annular recessed part formed in the end surface of the casing 3 of the rotation side in between. These recesses 28 and 29 accumulate the intruded earth and sand to form a protective wall generating space 30 by the earth and sand. This space 30 has a function of actively storing the earth and sand that has passed through the second labyrinth seal 27. Thus, the earth and sand collected in the earth and sand storage space 30 is dried and solidified in the space 30 and then functions as a blocking member that suppresses the intruding earth and sand from entering further inside.
It is desirable to arrange the recesses 28 and 29 described above as opposed to each other as much as possible in order to form a space 30 for sediment storage.

Next, the operation of the embodiment of the earth and sand intrusion prevention device of the present invention described above and the speed reduction device for traveling of a hydraulic excavator provided with the same will be described with reference to FIGS.
When pressure oil is supplied to and discharged from the hydraulic motor 2 from the outside and the output shaft 2A is rotationally driven, this rotation is decelerated in three stages by the reduction gear mechanisms 10, 14, and 18 in the casing 3, and the casing 3 is rotated with high torque. Power is transmitted. Then, the crawler belt is driven by the rotation output transmitted to the casing 3. Thereby, the hydraulic excavator can be driven.

  At this time, the floating seal 22 is such that the sliding contact surface 23B of the seal ring 23 provided on the rotating casing 3 is in contact with the sliding contact surface 23B of the seal ring 23 provided on the stationary casing 1 which is the counterpart. And sliding between the casing 1 on the fixed side and the casing 3 on the rotating side. As a result, the lubricating oil in the casings 1 and 3 can be prevented from leaking to the outside, and earth and sand can be prevented from entering between the two.

  By the way, when the speed reducer described above is installed in a traveling device of a construction machine such as a hydraulic excavator, earth and sand, in particular, clayey earth and sand are introduced from the gap of the second labyrinth seal 27 depending on the situation of the construction machine operation site. Break into. This earth and sand is trapped in the earth storage space 30 and accumulated.

  The earth and sand accumulated and filled in the earth and sand storage space 30 described above are dried and solidified over time, and are transformed so as to exhibit a function as an annular shielding member in the space 30. The annular shielding member in the space 30 then suppresses further intrusion of earth and sand entering through the gap of the second labyrinth seal 27. Thereby, the damage of the floating seal 22 by earth and sand is suppressed as much as possible.

  As a result, the life of the reduction gear can be extended, and the maintenance time of the reduction gear can be reduced. Therefore, the downtime of the construction machine equipped with the reduction gear can be reduced and the operation time of the construction machine can be improved. Can do.

Further, according to the embodiment of the present invention, it is not necessary to increase the number of parts and man-hours, so that it is inexpensive.
In addition, although the earth and sand reservoir space 30 in the earth and sand intrusion prevention device of the present invention described above is formed by the recessed portions 28 and 29 having a semicircular cross section, it may be formed in other shapes such as a triangle. .
Further, in the above-described embodiment of the present invention, the floating seal used in the reduction device for traveling the hydraulic excavator has been described as an example. However, the present invention is not limited to this, and for example, the upper swing body of the hydraulic excavator is used. You may apply to the deceleration device for turning for making it turn on a lower traveling body. Further, the present invention may be applied to upper and lower guide rollers, idler wheels and the like for guiding a crawler track of a hydraulic excavator, and further widely applicable to bearing devices of various industrial machines.

It is a longitudinal cross-sectional view which shows the traveling speed reducer provided with one Embodiment of the earth-and-sand penetration prevention apparatus of this invention. It is sectional drawing which expands and shows one Embodiment of the earth-and-sand penetration prevention apparatus of this invention shown in FIG.

Explanation of symbols

1,3 Casing 1B, 4B Protruding part 2 Hydraulic motor (rotation source)
DESCRIPTION OF SYMBOLS 22 Floating seal 25 Sediment invasion prevention apparatus 26 1st labyrinth 27 2nd labyrinth 28 Annular dent 29 Annular dent 30 Space for the protection wall generation by earth and sand

Claims (4)

  In a sand and sand intrusion prevention device provided with a floating seal that suppresses intrusion of earth and sand from a gap between one rotating casing and the other fixed casing, an opposing portion between the one casing and the other casing A first labyrinth seal provided; and a space for generating a protective wall made of earth and sand provided at an opposing portion between the one casing and the other casing outside the first labyrinth seal. Sediment prevention device.   A pair of seal rings that are arranged to face each other on the inner peripheral side of one rotating casing and the other fixed casing, and whose opposing surfaces in the axial direction are in sliding contact with each other, the outer peripheral surface of each seal ring, and each of the seal rings In the earth and sand intrusion prevention device provided with a floating seal comprising an O-ring provided between each of the inner peripheral surfaces of the casings, a first labyrinth seal and a first labyrinth seal provided at a facing portion between the one casing and the other casing An apparatus for preventing invasion of earth and sand, comprising: a labyrinth seal of No. 2; and a space for generating a protective wall made of earth and sand provided between the first labyrinth seal and the second labyrinth seal in the facing portion.   A pair of seal rings that are arranged to face each other on the inner peripheral side of one rotating casing and the other fixed casing, and whose opposing surfaces in the axial direction are in sliding contact with each other, the outer peripheral surface of each seal ring, and each of the seal rings In the earth and sand intrusion prevention device provided with a floating seal comprising an O-ring provided between each of the inner peripheral surfaces of the casings, a first labyrinth seal and a first labyrinth seal provided at a facing portion between the one casing and the other casing 2 labyrinth seals, and a concave portion provided so as to form a space for generating a protective wall made of earth and sand at the facing portion between the first labyrinth seal and the second labyrinth seal. Soil and sand intrusion prevention device.   A fixed-side casing provided with a rotation source, a rotation-side casing provided to be rotatable relative to the fixed-side casing and driven by the rotation source, and a reduction gear mechanism provided in the rotation-side casing And a decelerating device comprising a floating seal provided between the stationary casing and the rotating casing, comprising the earth and sand intrusion prevention device according to any one of claims 1 to 3. To reduce the speed.

Images