Crawler work machinery

Abstract

The bulldozer (1) includes a right first oil circuit (101R), a right second oil circuit (102R), and a right third oil circuit (103R). The right first oil circuit (101R) guides a portion of the lubricating oil discharged from the hydraulic pump (81) to the right steering brake (50R). The right second oil circuit (102R) guides a portion of the lubricating oil discharged from the hydraulic pump (81) to the right planetary gear mechanism (30R). The right third oil circuit (103R) guides at least a portion of the lubricating oil that has passed through the right planetary gear mechanism (30R) to the right steering brake (50R). At least a portion of the right planetary gear mechanism (30R) is arranged on the inner side of the right steering brake (50R) in a radial direction perpendicular to the axis of the input shaft (26).

Description

Technical Field

[0001] The present disclosure relates to a track-type work machine. Background Art

[0002] In a crawler type working machine (such as a bulldozer), the power of the engine is transmitted to the left and right drive wheels via a transmission, and the left and right crawlers are driven by the left and right drive wheels. In such a crawler type working machine, left and right rotation is performed by hydraulically controlling the left and right steering clutches and steering brakes provided corresponding to the left and right drive wheels.

[0003] Patent Document 1 proposes a method of supplying a part of the lubricating oil supplied from a hydraulic pump to a steering clutch to a steering brake for the purpose of efficiently utilizing the lubricating oil.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2017-71357 Summary of the invention

[0007] Problems that the invention will solve

[0008] However, in order to reduce the size of the steering clutch, it is conceivable to provide a planetary gear mechanism between the input shaft and the output shaft. However, Patent Document 1 does not study the efficient use of lubricating oil when the planetary gear mechanism is provided.

[0009] An object of the present disclosure is to provide a crawler type working machine capable of efficiently utilizing lubricating oil.

[0010] Means for solving problems

[0011] A crawler work machine according to one aspect of the present disclosure comprises a planetary gear mechanism, a steering clutch, a steering brake, a hydraulic pump, a first oil circuit, a second oil circuit, and a third oil circuit. The planetary gear mechanism is arranged between an input shaft and an output shaft. The steering clutch switches the transmission and the cutting off of the rotation from the input shaft to the output shaft based on the planetary gear mechanism. The steering brake brakes the rotation of the output shaft. The hydraulic pump discharges lubricating oil. The first oil circuit guides a part of the lubricating oil discharged from the hydraulic pump to the steering brake. The second oil circuit guides a part of the lubricating oil discharged from the hydraulic pump to the planetary gear mechanism. The third oil circuit guides at least a part of the lubricating oil that has passed through the planetary gear mechanism to the steering brake. At least a part of the planetary gear mechanism is arranged on the inner side of the steering brake in a radial direction perpendicular to the axis of the input shaft.

[0012] Effects of the Invention

[0013] According to the crawler type working machine of the present disclosure, lubricating oil can be used efficiently. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a perspective view of a bulldozer as an example of a crawler type working machine.

[0015] Figure 2 This is a cross-sectional diagram of the power transmission system of a bulldozer.

[0016] Figure 3 This is a schematic diagram of the power transmission system of a bulldozer.

[0017] Figure 4 It is a cross-sectional view showing the structure of the lubricating oil passage and its surroundings.

[0018] Figure 5 This is a schematic diagram for explaining the flow of lubricating oil. DETAILED DESCRIPTION

[0019] (Configuration of Bulldozer 1)

[0020] Figure 1 It is a perspective view of a bulldozer 1 as an example of a crawler type working machine. Figure 2 It is a cross-sectional structural diagram of a power transmission system of the bulldozer 1 . Figure 3 It is a schematic system configuration diagram of a power transmission system of the bulldozer 1 .

[0021] The bulldozer 1 includes left and right travel devices 4L and 4R having left and right sprockets 2L and 2R and left and right crawler tracks 3L and 3R, a dozer blade 5 provided at the front of the vehicle, and a soil ripping device 6 provided at the rear of the vehicle.

[0022] The bulldozer 1 can perform operations such as compacting soil using a dozer blade 5 and operations such as crushing and excavating using a soil ripping device 6 .

[0023] The bulldozer 1 includes an engine 10 , a power transmission device 20 , left and right planetary gear mechanisms 30L, 30R, left and right steering clutches 40L, 40R, left and right steering brakes 50L, 50R, left and right output shafts 60L, 60R, left and right final reduction devices 70L, 70R, and a lubricating oil supply unit 80 .

[0024] The power transmission device 20 transmits the power from the engine 10 to the left and right planetary gear mechanisms 30L and 30R. The power transmission device 20 includes a power take-off device (power output device) 21 , a torque converter 22 , a transmission 23 , a pinion gear 24 , a bevel gear 25 , and an input shaft 26 .

[0025] The power take-off device 21 distributes the power from the engine 10 to the torque converter 22 and the lubricating oil supply unit 80. The torque converter 22 transmits the power of the engine 10 transmitted from the power take-off device 21 to the transmission 23 via a fluid. The transmission 23 changes the speed of the rotational motion transmitted from the torque converter 22. The transmission 23 can switch between forward and reverse. The transmission 23 is connected to the pinion 24. The power from the transmission 23 is transmitted to the input shaft 26 via the pinion 24 and the bevel gear 25.

[0026] The left and right planetary gear mechanisms 30L, 30R are disposed between the input shaft 26 and the left and right output shafts 60L, 60R. The left and right planetary gear mechanisms 30L, 30R include left and right ring gears 31L, 31R, left and right planetary gears 32L, 32R, left and right sun gears 33L, 33R, and left and right planetary carriers 34L, 34R.

[0027] The left and right ring gears 31L and 31R are connected to the input shaft 26. The left and right planetary gears 32L and 32R are arranged inside the left and right ring gears 31L and 31R in the radial direction perpendicular to the axis of the input shaft 26. The left and right planetary gears 32L and 32R are arranged between the left and right ring gears 31L and 31R and the left and right sun gears 33L and 33R. The left and right planetary gears 32L and 32R mesh with the left and right ring gears 31L and 31R and the left and right sun gears 33L and 33R. The left and right sun gears 33L and 33R are rotatably mounted on the input shaft 26. The left and right sun gears 33L and 33R are arranged inside the left and right planetary gears 32L and 32R in the radial direction. The left and right sun gears 33L and 33R are connected to the left and right steering clutches 40L and 40R. The left and right planetary carriers 34L and 34R are connected to the left and right planetary gears 32L and 32R and the left and right output shafts 60L and 60R.

[0028] The left and right steering clutches 40L and 40R are wet multi-plate clutches that can be engaged or released with respect to the left and right sun gears 33L and 33R. The left and right steering clutches 40L and 40R switch the transmission and cutoff of the rotational power from the input shaft 26 to the left and right output shafts 60L and 60R under the action of the left and right planetary gear mechanisms 30L and 30R.

[0029] Specifically, if the left steering clutch 40L is engaged and the left sun gear 33L is directly connected to the first clutch gear 91, the first clutch gear 91 cannot rotate (described later), and therefore the left sun gear 33L cannot rotate either. Thus, the rotation of the input shaft 26 is transmitted to the left output shaft 60L via the left ring gear 31L, the left planetary gear 32L, and the left planetary carrier 34L. In addition, if the left steering clutch 40L is opened and the left sun gear 33L becomes a free rotation state, the rotation from the input shaft 26 to the left output shaft 60L is cut off. Similarly, the right steering clutch 40R also switches the transmission and cutoff of the rotation from the input shaft 26 to the right output shaft 60R according to its engagement and opening.

[0030] In addition, if Figure 3 As shown, the left steering clutch 40L is provided with a first clutch gear 91, which is connected to an idler gear 93 and a pinion gear 94. In addition, the right steering clutch 40R is provided with a second clutch gear 92, which is connected to the idler gear 93 and the pinion gear 94 via a first transmission gear 95, a countershaft 96, and a second transmission gear 97. Moreover, a pinion gear shaft 94a connected to the pinion gear 94 is fixed by a fixing member 98 so as not to rotate. Therefore, no rotational power is applied from the left and right steering clutches 40L and 40R to the left and right sun gears 33L and 33R.

[0031] Here, the fixing member 98 is detachably fixed to a housing (not shown). When the fixing member 98 is removed from the housing, the fixing member 98 can also be removed from the pinion gear 94. Thus, the fixing of the pinion gear 94 by the fixing member 98 is released.

[0032] When the fixing member 98 is released from the pinion 94, a rotation motor (not shown) may be connected to the pinion shaft 94a. In this case, if the left and right steering clutches 40L and 40R are engaged, and the rotational power of the rotation motor is transmitted to the left and right sun gears 33L and 33R via the left and right steering clutches 40L and 40R, the left and right sun gears 33L and 33R rotate inversely at the same speed. As a result, a speed difference is generated between the left and right output shafts 60L and 60R, and the bulldozer 1 can slowly rotate left and right.

[0033] The left and right steering brakes 50L and 50R brake the rotation of the left and right output shafts 60L and 60R. The left and right steering brakes 50L and 50R are wet multi-plate clutches that can be engaged or released with respect to the left and right output shafts 60L and 60R.

[0034] When the left steering brake 50L is engaged, the rotation of the left output shaft 60L is braked. As a result, the rotation of the left final reduction device 70L connected to the left sprocket 2L is reduced. When the right steering brake 50R is engaged, the rotation of the right output shaft 60R is braked. As a result, the rotation of the right final reduction device 70R connected to the right sprocket 2R is reduced.

[0035] The lubricating oil supply unit 80 includes a hydraulic pump 81 , a lubricating oil passage 82 , and a lubricating oil tank 83 .

[0036] The hydraulic pump 81 is driven by the power of the engine 10 transmitted from the power take-off device 21. The hydraulic pump 81 discharges lubricating oil from a lubricating oil tank 83 to a lubricating oil passage 82. In the present embodiment, the hydraulic pump 81 is a fixed displacement type pump.

[0037] The lubricating oil circuit 82 includes a first oil supply circuit 100, a second oil supply circuit 110, left and right first oil circuits 101L, 101R, left and right second oil circuits 102L, 102R, left and right third oil circuits 103L, 103R, left and right fourth oil circuits 104L, 104R, left and right fifth oil circuits 105L, 105R, and left and right discharge oil circuits 106L, 106R.

[0038] The first oil supply passage 100 is connected to the second oil supply passage 110, the left and right first oil passages 101L, 101R, and the hydraulic pump 81. The first oil supply passage 100 supplies lubricating oil discharged from the hydraulic pump 81 to the second oil supply passage 110 and the left and right first oil passages 101L, 101R.

[0039] The left and right first oil passages 101L and 101R guide a part of the lubricating oil discharged from the hydraulic pump 81 to the left and right steering brakes 50L and 50R.

[0040] The second oil supply passage 110 is connected to the first oil supply passage 100 and the inside of the input shaft 26. The second oil supply passage 110 guides a part of the lubricating oil discharged from the hydraulic pump 81 to the left and right second oil passages 102L, 102R and the left and right fourth oil passages 104L, 104R.

[0041] The left and right second oil passages 102L and 102R guide a portion of the lubricating oil discharged from the hydraulic pump 81 to the left and right planetary gear mechanisms 30L and 30R. The left and right third oil passages 103L and 103R guide at least a portion of the lubricating oil passing through the left and right planetary gear mechanisms 30L and 30R to the left and right steering brakes 50L and 50R. In the present embodiment, the left and right third oil passages 103L and 103R guide all of the lubricating oil passing through the left and right planetary gear mechanisms 30L and 30R to the left and right steering brakes 50L and 50R.

[0042] The left and right fourth oil passages 104L and 104R guide a part of the lubricating oil discharged from the hydraulic pump 81 to the left and right steering clutches 40L and 40R. The left and right fifth oil passages 105L and 105R guide at least a part of the lubricating oil that has passed through the left and right steering clutches 40L and 40R to the left and right steering brakes 50L and 50R. Specifically, the left and right fifth oil passages 105L and 105R guide all of the lubricating oil that has passed through the left and right steering clutches 40L and 40R to the left and right steering brakes 50L and 50R via the left and right planetary gear mechanisms 30L and 30R and the left and right third oil passages 103L and 103R.

[0043] Thus, in this embodiment, all the lubricating oil guided to the left and right planetary gear mechanisms 30L, 30R and the steering clutches 40L, 40R is guided to the left and right steering brakes 50L, 50R via the left and right third oil passages 103L, 103R and the left and right fifth oil passages 105L, 105R.

[0044] The left and right discharge oil passages 106L, 106R guide the lubricating oil having passed through the left and right steering brakes 50L, 50R to the lubricating oil tank 83 .

[0045] (Configuration of the Lubricating Oil Passage 82 and Its Surroundings)

[0046] Figure 4 82 is a cross-sectional view showing the structure of the lubricating oil passage 82 and its surroundings. Figure 4 , a cross section perpendicular to the axis of the input shaft 26 is shown. The structure around the lubricating oil passage 82 is basically bilaterally symmetrical, so the structure on the right side will be described below.

[0047] The right steering clutch 40R includes a rotating member 41 , a clutch housing 42 , a plurality of clutch discs 43 , a plurality of clutch plates 44 , and a clutch piston 45 .

[0048] The rotating member 41 is supported by the input shaft 26 and rotates around the axis of the input shaft 26. The clutch housing 42 is arranged to be relatively rotatable relative to the rotating member 41. The clutch housing 42 surrounds the outer sides of each clutch disc 43 and each clutch plate 44. Each clutch disc 43 is supported by the rotating member 41. Each clutch plate 44 is supported by the clutch housing 42. Each clutch disc 43 and each clutch plate 44 are alternately arranged in an axial direction parallel to the axis of the input shaft 26. If the clutch piston 45 is supplied with working oil, each clutch disc 43 and each clutch plate 44 are pressed against each other. As a result, the right steering clutch 40R becomes engaged.

[0049] The right steering brake 50R includes a rotating member 51 , a brake housing 52 , a plurality of fixing plates 53 , a plurality of brake disks 54 , and a brake piston 55 .

[0050] The rotating member 51 is fixed to the right output shaft 60R and rotates around the axis of the right output shaft 60R. The brake housing 52 can rotate relative to the rotating member 51. In the present embodiment, the brake housing 52 is fixed, and the brake housing 52 itself does not rotate. The brake housing 52 surrounds the outer sides of each fixing plate 53 and each brake disc 54. Each fixing plate 53 is mounted on the brake housing 52. Each fixing plate 53 can also move slightly in the axial direction relative to the brake housing 52. Each brake disc 54 is supported by the rotating member 51. Each brake disc 54 can also move slightly in the axial direction relative to the rotating member 51.

[0051] The fixing plates 53 and the brake discs 54 are alternately arranged in the axial direction. The fixing plates 53 and the brake discs 54 are pressed against each other by a spring (e.g., a disc spring, a coil spring, etc.) not shown in the figure. When the brake piston 55 is supplied with hydraulic oil, the fixing plates 53 and the brake discs 54 are moved away from each other. As a result, the right steering brake 50R is in a non-braking state.

[0052] Here, at least a portion of the right planetary gear mechanism 30R is arranged radially inwardly of the right steering brake 50R. Specifically, the right ring gear 31R is arranged radially inwardly of each brake disc 54. In addition, the right planetary gear 32R and the right sun gear 33R arranged on the inner side of the right ring gear 31R are also arranged radially inwardly of each brake disc 54. Moreover, a portion of the right planetary carrier 34R connected to the right planetary gear 32R and the right output shaft 60R is also arranged radially inwardly of each brake disc 54.

[0053] Moreover, at least a part of the right steering clutch 40R is arranged radially inwardly of the right steering brake 50R. Specifically, each clutch disc 43 and each clutch plate 44 are arranged radially inwardly of each brake disc 54.

[0054] In this specification, "at least a portion of the X member is arranged radially inwardly of the Y member" means that, when viewed from an axial direction parallel to the axis of the input shaft 26, the shortest distance between the X member and the axis is shorter than the shortest distance between the Y member and the axis. In this case, the position of the X member in the axial direction and the position of the Y member in the axial direction may partially or entirely overlap or may not overlap.

[0055] In the present embodiment, the right steering brake 50R, the right planetary gear mechanism 30R, and the right steering clutch 40R are arranged in this order from the right side, but the arrangement order in the axial direction can be changed as appropriate.

[0056] Next, the flow of lubricating oil will be described. Figure 5 This is a schematic diagram for explaining the flow of lubricating oil.

[0057] The lubricating oil discharged from the hydraulic pump 81 is distributed to the right first oil passage 101R, the right second oil passage 102R, and the right fourth oil passage 104R via the first oil supply passage 100 and the second oil supply passage 110. The distribution ratio to each oil passage can be adjusted as appropriate by changing the diameter of each oil passage.

[0058] The lubricating oil distributed to the right fourth oil passage 104R lubricates the right steering clutch 40R and is then guided to the right planetary gear mechanism 30R from the right fifth oil passage 105R by centrifugal force.

[0059] The lubricating oil distributed to the right second oil passage 102R lubricates the right planetary gear mechanism 30R and is then guided to the right steering brake 50R from the right third oil passage 103R by centrifugal force together with the lubricating oil guided to the right planetary gear mechanism 30R from the right fifth oil passage 105R.

[0060] The lubricating oil distributed to the right first oil passage 101R, together with the lubricating oil guided to the right steering brake 50R from the right third oil passage 103R, lubricates the right steering brake 50R and is then guided to the lubricating oil tank 83 from the right discharge oil passage 106R by centrifugal force.

[0061] (feature)

[0062] (1) The bulldozer 1 includes a right first oil passage 101R, a right second oil passage 102R, and a right third oil passage 103R. The right first oil passage 101R guides a portion of the lubricating oil discharged from the hydraulic pump 81 to the right steering brake 50R. The right second oil passage 102R guides a portion of the lubricating oil discharged from the hydraulic pump 81 to the right planetary gear mechanism 30R. The right third oil passage 103R guides at least a portion of the lubricating oil that has passed through the right planetary gear mechanism 30R to the right steering brake 50R. At least a portion of the right planetary gear mechanism 30R is arranged on the inner side of the right steering brake 50R in a radial direction perpendicular to the axis of the input shaft 26.

[0063] Therefore, the lubricating oil can be guided from the right planetary gear mechanism 30R to the right steering brake 50R by centrifugal force via the third oil passage 103R, so the lubricating oil used for lubricating the right planetary gear mechanism 30R can also be used for lubricating the right steering brake 50R. Therefore, the lubricating oil supplied from the hydraulic pump 81 can be efficiently used, so the capacity of the hydraulic pump 81 can be reduced. This effect can also be obtained in the left steering brake 50L.

[0064] (2) The bulldozer 1 includes a right fourth oil passage 104R and a right fifth oil passage 105R. The right fourth oil passage 104R guides a portion of the lubricating oil discharged from the hydraulic pump 81 to the right steering clutch 40R. The right fifth oil passage 105R guides at least a portion of the lubricating oil that has passed through the right steering clutch 40R to the right steering brake 50R. At least a portion of the right steering clutch 40R is arranged radially inward of the right steering brake 50R.

[0065] Therefore, the lubricating oil can be guided from the right steering clutch 40R to the right steering brake 50R by centrifugal force via the fifth oil passage 105R, so the lubricating oil used for lubricating the right steering clutch 40R can also be used for lubricating the right steering brake 50R. Therefore, the lubricating oil supplied from the hydraulic pump 81 can be used more efficiently, so the capacity of the hydraulic pump 81 can be further reduced. This effect can also be obtained in the left steering brake 50L.

[0066] (Variation of the embodiment)

[0067] The present invention is not limited to the above-described embodiments, and various changes or modifications may be made without departing from the scope of the present invention.

[0068] (Variant 1)

[0069] In the above embodiment, the left and right third oil passages 103L and 103R guide all the lubricating oil passing through the left and right planetary gear mechanisms 30L and 30R to the left and right steering brakes 50L and 50R, but the present invention is not limited thereto. The left and right third oil passages 103L and 103R may guide only a part of the lubricating oil passing through the left and right planetary gear mechanisms 30L and 30R to the left and right steering brakes 50L and 50R. In this case, the remaining part of the lubricating oil passing through the left and right planetary gear mechanisms 30L and 30R may be directly recovered to the lubricating oil tank 83.

[0070] (Variant 2)

[0071] In the above embodiment, the left and right fifth oil passages 105L and 105R guide all the lubricating oil passing through the left and right steering clutches 40L and 40R to the left and right steering brakes 50L and 50R, but the present invention is not limited thereto. The left and right fifth oil passages 105L and 105R may guide only a part of the lubricating oil passing through the left and right steering clutches 40L and 40R to the left and right steering brakes 50L and 50R. In this case, the remaining part of the lubricating oil passing through the left and right steering clutches 40L and 40R may be directly recovered to the lubricating oil tank 83.

[0072] (Variant 3)

[0073] In the above embodiment, the left and right fifth oil passages 105L and 105R are connected from the left and right steering clutches 40L and 40R to the left and right planetary gear mechanisms 30L and 30R, but the present invention is not limited thereto. For example, the left and right fifth oil passages 105L and 105R may be directly connected from the left and right steering clutches 40L and 40R to the left and right steering brakes 50L and 50R. Alternatively, the left and right fifth oil passages 105L and 105R may be directly connected from the left and right steering clutches 40L and 40R to the lubricating oil tank 83.

[0074] Description of Reference Numerals

[0075] 1. Bulldozer

[0076] 10 Engine

[0077] 20 Power transmission device

[0078] 26 Input shaft

[0079] Planetary gear mechanism around 30L and 30R

[0080] 40L, 40R left and right steering clutch

[0081] Steering brake for 50L and 50R

[0082] Output shaft around 60L and 60R

[0083] Final reduction device around 70L and 70R

[0084] 80 Lubricating oil supply unit

[0085] 81 Hydraulic Pump

[0086] 82 Lubrication oil circuit

[0087] 100 Oil supply line

[0088] 101L, 101R left and right first oil circuit

[0089] 102L, 102R left and right second oil circuit

[0090] The third oil circuit of 103L and 103R

[0091] 104L, 104R left and right fourth oil circuit

[0092] 105L, 105R left and right fifth oil circuit

[0093] 106L, 106R left and right oil discharge channels

Claims

1. A crawler type working machine, characterized in that: have: engine; A transmission that changes the speed of the power of the engine; an input shaft that transmits power from the transmission; a planetary gear mechanism disposed between the input shaft and the output shaft; a steering clutch that switches transmission and interruption of the rotational power from the input shaft to the output shaft based on the planetary gear mechanism; a steering brake that brakes the rotation of the output shaft; a hydraulic pump that discharges lubricating oil; a first oil passage that guides a portion of the lubricating oil discharged from the hydraulic pump to the steering brake; a second oil passage that guides a portion of the lubricating oil discharged from the hydraulic pump to the planetary gear mechanism; as well as a third oil passage that guides at least a portion of the lubricating oil that has passed through the planetary gear mechanism to the steering brake, a fourth oil passage that guides a portion of the lubricating oil discharged from the hydraulic pump to the steering clutch; as well as a fifth oil passage that guides at least a portion of the lubricating oil that has passed through the steering clutch to the planetary gear mechanism, At least a portion of the planetary gear mechanism is arranged on an inner side than the steering brake in a radial direction perpendicular to an axial center of the input shaft.

2. The crawler working machine according to claim 1, characterized in that: The planetary gear mechanism has: a ring gear connected to the input shaft; a planetary gear disposed inside the ring gear in the radial direction; a sun gear, which is arranged inside the planetary gears in the radial direction and is connected to the steering clutch; as well as a planet carrier connected to the planetary gear and the output shaft, The steering brake has: a rotating member that rotates together with the output shaft; a brake housing capable of relative rotation with respect to the rotating member; a plurality of fixing plates mounted on the brake housing; as well as a plurality of brake discs mounted on the rotating member, The ring gear is arranged on the inner side than the plurality of brake discs in the radial direction.

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