JP6204777B2 - Industrial vehicle transmission - Google Patents

Description

  The present invention relates to a transmission mounted on an industrial vehicle.

  Forklifts as industrial vehicles, for example, as shown in Patent Document 1, the power of a torque converter connected to an engine is transmitted to drive wheels via a transmission. The case of the transmission houses a hydraulic clutch or gear. The hydraulic clutch is operated by supplying hydraulic oil by driving a hydraulic pump. For example, the hydraulic oil is stored in the case of the transmission as a storage portion, and is sucked into the hydraulic pump through the suction portion of the case.

JP 2007-99413 A

  For example, when sudden braking is applied during traveling, the oil level of the hydraulic oil stored in the reservoir may fluctuate abruptly, and the hydraulic pump causes the air in the case to pass through the suction part due to the oil level fluctuation. May be inhaled. As a result, there are cases where the clutch does not operate and the traveling may become unstable.

  This invention was made paying attention to the problem which exists in such a prior art, The objective is to provide the transmission of the industrial vehicle which suppressed the fluctuation | variation of the oil level of hydraulic fluid. is there.

  An industrial vehicle transmission that solves the above problems includes a case, a clutch that is housed in the case and that is hydraulically operated, and a suction portion that receives hydraulic oil stored in the case by a hydraulic pump; A partition plate extending from an inner side surface of the case to an inner side of the case, and partitioning a portion in which the hydraulic oil is stored in the case.

  According to this configuration, the partition plate arranged in the case restricts the movement of the hydraulic oil stored in the case. For this reason, even when the force which produces the fluctuation | variation of an oil level with respect to hydraulic fluid is added, the movement of hydraulic fluid is controlled by a partition plate, and the fluctuation | variation of an oil level is suppressed. Therefore, the hydraulic pump is prevented from sucking air through the suction portion.

  In the above transmission for an industrial vehicle, it is preferable that the partition plate is positioned at the height of the oil level in a stationary state. According to this configuration, the partition plate is not immersed in the hydraulic oil, and a space that allows movement of the hydraulic oil is not formed between the partition plate and the oil surface. For this reason, fluctuations in the oil level are suppressed.

  In the transmission for an industrial vehicle, the suction portion may include an oil filter, and the partition plate may extend from the inner surface located on the opposite side of the oil filter. According to this configuration, the movement of the hydraulic oil around the oil filter is restricted. For this reason, the oil filter is maintained in a state immersed in the hydraulic oil, and the hydraulic pump is prevented from sucking air through the oil filter.

  In the above transmission for an industrial vehicle, the partition plate may be integrated with the case. According to this structure, the process of retrofitting a partition plate is unnecessary and it is suppressed that a manufacturing cost increases.

  A transmission for an industrial vehicle that solves the above problems includes a case, a clutch that is housed in the case and that is hydraulically operated, a suction portion that receives hydraulic oil stored in the case by a hydraulic pump, A shielding plate that extends from the bottom surface of the case to the inside of the case and protrudes from a height position of the oil surface that is in a stationary state, and that blocks movement of hydraulic oil in the case.

  According to this configuration, the shielding plate arranged in the case regulates the movement of the hydraulic oil stored in the case. For this reason, even when the force which produces the fluctuation | variation of an oil level with respect to hydraulic fluid is added, the movement of hydraulic fluid is controlled by a shielding board, and the fluctuation | variation of an oil level is suppressed. Therefore, the hydraulic pump is prevented from sucking air through the suction portion.

  In the above transmission for an industrial vehicle, the case includes a transmission case containing the clutch and a PTO case containing a PTO unit, the suction portion is located in the PTO case, and the shielding plate is It is good to be located between the mission case and the PTO case.

  According to this configuration, even when a force that may cause a change in the oil level is applied to the hydraulic oil, the movement of the hydraulic oil around the suction portion is restricted. For this reason, the state where the suction part is immersed in the hydraulic oil can be maintained.

  In the above transmission for an industrial vehicle, it is preferable that a communication hole that communicates the inside of the transmission case and the inside of the PTO case is formed in the shielding plate. According to this configuration, the hydraulic oil that has moved to the mission case is returned to the PTO case through the communication hole. For this reason, the periphery of the suction portion is filled with hydraulic oil.

  According to this invention, the fluctuation | variation of the oil level of hydraulic fluid can be suppressed.

The side view of a forklift. Sectional drawing of the mission case, PTO case, and torque converter case in 1st Embodiment. Sectional drawing of the mission case, PTO case, and torque converter case in 2nd Embodiment. The front view which expanded a part of shielding board.

(First embodiment)
Hereinafter, a first embodiment of a transmission for an industrial vehicle will be described with reference to FIGS. 1 and 2.

  As shown in FIG. 1, a forklift 10 serving as an industrial vehicle is equipped with a cargo handling device 12 having a fork 11 serving as a cargo handling tool. An engine 14, a torque converter 15, a PTO (power take-off) unit 16, and a transmission 17 are mounted on the vehicle body 13 of the forklift 10. The engine 14 is mounted on the rear portion of the vehicle body 13, and the torque converter 15, the PTO unit 16, and the transmission 17 are arranged in this order from the engine 14 toward the front portion of the vehicle body 13. The torque converter 15, the PTO unit 16, and the transmission 17 are coupled so that the output of the engine 14 can be transmitted. In this embodiment, the PTO unit 16 and the transmission 17 are transmissions.

The transmission 17 includes a forward / reverse clutch 18 and a gear (not shown). In addition, a hydraulic pump 19 that supplies hydraulic oil to the clutch 18 is mounted on the vehicle body 13.
As shown in FIG. 2, a PTO case 21 of the PTO unit 16 is joined to the torque converter case 20 of the torque converter 15. A transmission case 22 of the transmission 17 is joined to the PTO case 21. The clutch 18 and the gear are accommodated in the mission case 22. In this embodiment, a PTO case 21 and a transmission case 22 constitute a transmission case 23.

  The PTO case 21 accommodates an oil filter (suction filter) 25 that constitutes a suction portion. The oil filter 25 is immersed in hydraulic oil stored in the case 23. The oil filter 25 only needs to be immersed in the hydraulic oil at a portion that sucks the hydraulic oil. The hydraulic oil stored in the case 23 is sucked into the hydraulic pump 19 through the oil filter 25 while foreign matter is captured by the oil filter 25. The hydraulic pump 19 supplies the sucked hydraulic oil to the clutch 18 of the transmission 17.

  On the inner side surface 26 of the mission case 22, there is a partition plate 27 that extends inward of the case 23 and partitions the inside of the case 23. The partition plate 27 extends in the horizontal direction and protrudes from the inner side surface 26. Further, the partition plate 27 is integrated with the mission case 22. The partition plate 27 is a cast article together with the mission case 22.

  The partition plate 27 is located at the height of the oil level of the hydraulic oil stored in the case 23. Thereby, the partition plate 27 partitions the part in which the hydraulic oil is stored in the case 23. And the partition plate 27 has covered a part of part in which hydraulic fluid is stored in the mission case 22 from upper direction. For this reason, a part of the hydraulic oil is stored below the partition plate 27. In addition, the height of the oil surface of the working oil that defines the position of the partition plate 27 is the height of the oil surface in a stationary state where the oil surface does not vary. The height of the oil level is defined by the amount of hydraulic oil stored. And an oil level is located upward, so that there is much quantity of the hydraulic oil stored.

  The inner side surface having the partition plate 27 is the inner side surface 26 of the mission case 22 in the case 23. On the other hand, the oil filter 25 is in the PTO case 21 joined to the mission case 22. For this reason, the partition plate 27 extends from the inner side surface 26 of the case 23 (transmission case 22) that is located on the opposite side of the oil filter 25. The inner side surface 26 is also an inner side surface of the case 23 that is positioned most forward of the forklift 10.

Hereinafter, the operation of the transmission will be described.
As shown in FIG. 2, it is assumed that the oil level of the hydraulic oil stored in the case 23 and in a stationary state is “H1”. When the forklift 10 is stopped or traveling normally, there is little fluctuation in the oil level of the hydraulic oil. That is, the oil filter 25 can maintain a state immersed in the hydraulic oil. Therefore, sufficient hydraulic oil is drawn into the hydraulic pump 19 through the oil filter 25.

  On the other hand, when the partition plate 27 is not arranged in the case 23 as in this embodiment, the oil level is changed to that shown in FIG. 2 when the vehicle is suddenly braked while traveling in the direction indicated by the arrow in FIG. It fluctuates greatly as indicated by the oil level H2 indicated by the broken line. That is, the oil level is greatly deviated and fluctuated in the traveling direction under the influence of the inertial force, and thereafter swings while repeatedly colliding with the inner surface of the case 23.

  When the oil level fluctuates greatly as described above, the oil filter 25 is exposed in the case 23 due to a decrease in the surrounding hydraulic oil. That is, the oil filter 25 is exposed to the air present in the case 23. Thereby, the air in the case 23 may be sucked into the hydraulic pump 19 through the oil filter 25.

  However, when the partition plate 27 is arranged in the case 23 as in this embodiment, even when the sudden braking is applied as described above by the action of the partition plate 27, the fluctuation of the oil level is suppressed. The partition plate 27 is positioned so as to cover a part of the oil surface H1 from above with reference to the oil surface H1 of the hydraulic oil in a stationary state. For this reason, when sudden braking is applied, the hydraulic oil tends to move in the traveling direction as described above, but the partition plate 27 becomes an obstacle and its movement is restricted. As a result, the oil level does not fluctuate as much as the oil level H2 indicated by the broken line in FIG. And the oil filter 25 can maintain the state immersed in hydraulic fluid by the fluctuation | variation of an oil level being suppressed. Therefore, sufficient hydraulic oil is sucked into the hydraulic pump 19 through the oil filter 25 immersed in the hydraulic oil.

Therefore, according to the present embodiment, the following effects can be obtained.
(1) The partition plate 27 arranged in the case 23 regulates the movement of the hydraulic oil stored in the case 23. For this reason, even when an inertial force is applied to the hydraulic oil when sudden braking is applied, the movement of the hydraulic oil is restricted by the partition plate 27, and fluctuations in the oil level can be suppressed. Accordingly, it is possible to prevent the hydraulic pump 19 from sucking air through the oil filter 25.

  (2) The partition plate 27 is located at the height of the oil level H1 in a stationary state. As a result, the partition plate 27 is not immersed in the hydraulic oil, and a space allowing the movement of the hydraulic oil is not formed between the partition plate 27 and the oil surface H1. For this reason, the fluctuation | variation of an oil level can be suppressed.

  (3) The partition plate 27 is disposed on the inner side surface 26 of the case 23 located on the opposite side to the oil filter 25. For this reason, when the movement of the hydraulic oil is restricted by the partition plate 27, the movement of the hydraulic oil around the oil filter 25 is also restricted. For this reason, the oil filter 25 is maintained in a state immersed in the hydraulic oil, and the hydraulic pump 19 can be prevented from sucking air through the oil filter 25.

(4) The partition plate 27 is integrated with the inner side surface 26. For this reason, the process of retrofitting the partition plate 27 is unnecessary, and it can suppress that manufacturing cost will increase.
(Second Embodiment)
Hereinafter, a second embodiment of an industrial vehicle will be described with reference to FIGS. 3 and 4. Note that, in the embodiments described below, the same reference numerals are given to the same configurations and the like as those of the embodiments already described, and the overlapping description is omitted or simplified.

  As shown in FIG. 3, in this embodiment, a shielding plate 28 is arranged in the case 23 instead of the partition plate 27 of the first embodiment. The shielding plate 28 is located between the PTO case 21 and the mission case 22. The shielding plate 28 extends inward of the case 23 from the bottom surface 29 of the mission case 22 which is the bottom surface of the case 23, in the vicinity of the joint portion between the PTO case 21 and the mission case 22. The shielding plate 28 extends in the vertical direction and protrudes from the bottom surface 29. Further, the shielding plate 28 protrudes from the oil level H1 in a stationary state where the oil level does not vary. In this embodiment, the shielding plate 28 is a separate component from the mission case 22 and is fixed to the bottom surface 29 of the mission case 22 by a fastener or the like.

  As shown in FIGS. 3 and 4, the shielding plate 28 is formed with a through hole 30 penetrating in the thickness direction of the shielding plate 28. The through hole 30 is a communication hole that communicates the inside of the PTO case 21 and the inside of the mission case 22 in a state where the shielding plate 28 is disposed on the bottom surface 29 of the mission case 22. The hydraulic fluid stored in the case 23 is divided and stored in both the PTO case 21 and the transmission case 22 by the shielding plate 28, but can move between the through holes 30.

Hereinafter, the operation of the transmission will be described.
When the shielding plate 28 is arranged in the case 23 as in this embodiment, even when the sudden braking is applied by the action of the shielding plate 28 as described above, the fluctuation of the oil level is suppressed. When sudden braking is applied, the hydraulic oil tends to move in the traveling direction as described above. However, the hydraulic oil in the PTO case 21 is restricted from moving in the direction toward the mission case 22 because the shielding plate 28 becomes an obstacle. As a result, the oil level does not fluctuate as much as the oil level H2 indicated by the broken line in FIG. Thereby, the oil filter 25 arrange | positioned at the PTO case 21 can maintain the state immersed in hydraulic fluid.

  On the other hand, the hydraulic oil can move from the mission case 22 toward the PTO case 21 through the through hole 30 of the shielding plate 28. For this reason, even when the hydraulic oil moves from the PTO case 21 toward the transmission case 22 when sudden braking is applied, the hydraulic oil is returned to the PTO case 21 through the through hole 30.

Therefore, according to the present embodiment, the following effects can be obtained.
(5) The shielding plate 28 disposed in the case 23 regulates the movement of the hydraulic oil stored in the case 23. For this reason, even when an inertial force is applied to the hydraulic oil when sudden braking is applied, the movement of the hydraulic oil is restricted by the shielding plate 28, and fluctuations in the oil level can be suppressed. Accordingly, it is possible to prevent the hydraulic pump 19 from sucking air through the oil filter 25.

(6) The movement of the hydraulic oil around the oil filter 25 is restricted by the shielding plate 28. For this reason, the state in which the oil filter 25 is immersed in hydraulic fluid can be maintained.
(7) Even if the hydraulic fluid moves from the PTO case 21 to the mission case 22, the hydraulic fluid can be returned to the PTO case 21 through the through hole 30 of the shielding plate 28. For this reason, the periphery of the oil filter 25 can be filled with hydraulic oil.

Each embodiment may be changed as follows.
In the first embodiment, the partition plate 27 may be a separate component from the transmission case 22 and may be fixed to the inner surface 26 with a fastener or the like.

  (Circle) in 1st Embodiment, the partition plate 27 may be arrange | positioned in the position higher than the position of the oil level H1 in a stationary state. In this case, a space is formed between the partition plate 27 and the oil surface H1, and the degree of freedom of movement is increased. Therefore, the partitioning is performed so that the oil filter 25 is not exposed even if the hydraulic oil moves in the space. The position of the plate 27 may be adjusted.

  (Circle) in 1st Embodiment, the partition plate 27 may be arrange | positioned in the position lower than the position of the oil level H1. In this case, the partition plate 27 is disposed in the hydraulic oil. In this case, since the hydraulic oil easily moves over the partition plate 27, the position of the partition plate 27 may be adjusted so that the oil filter 25 is not exposed even if the hydraulic oil moves.

Each embodiment is not limited to a forklift, and may be applied to other industrial vehicles.
In each embodiment, the case having the partition plate 27 and the shielding plate 28 may be configured only by the mission case 22. In this case, the transmission is configured only by the transmission 17. The mission case 22 is directly joined to the torque converter case 20.

  DESCRIPTION OF SYMBOLS 10 ... Forklift, 16 ... PTO unit, 17 ... Transmission, 18 ... Clutch, 19 ... Hydraulic pump, 21 ... PTO case, 22 ... Transmission case, 23 ... Case, 25 ... Oil filter, 26 ... Inner side, 27 ... Partition plate 28 ... Shielding plate, 29 ... Bottom, 30 ... Through hole, H1, H2 ... Oil level.

Claims (6)

And to case,
A clutch housed in the case and operated hydraulically;
A suction part through which hydraulic oil stored in the case is sucked by a hydraulic pump;
A partition for an industrial vehicle, comprising: a partition plate extending from an inner surface of the case to an inner side of the case and partitioning a portion where the hydraulic oil is stored in the case ;
The case is composed of a PTO case containing a PTO unit and a transmission case containing the clutch, which are sequentially arranged along the traveling direction of the industrial vehicle.
The transmission for an industrial vehicle, wherein the partition plate is integrally formed with the mission case and extends from an inner surface of the mission case toward the PTO case .   The transmission for an industrial vehicle according to claim 1, wherein the partition plate is positioned at a height of an oil level in a stationary state. The suction part includes an oil filter,
The transmission for an industrial vehicle according to claim 1, wherein the partition plate extends from the inner surface located on the side opposite to the oil filter. And to case,
A clutch housed in the case and operated hydraulically;
A suction part through which hydraulic oil stored in the case is sucked by a hydraulic pump;
A transmission for an industrial vehicle comprising: a shielding plate that extends from the bottom surface of the case to the inside of the case and protrudes from a height position of an oil surface that is stationary, and that blocks movement of hydraulic oil in the case. Because
The suction part includes an oil filter,
The oil filter is disposed on the bottom surface of the case and faces the shielding plate,
In the shielding plate, a through-hole penetrating in the plate thickness direction is formed,
The through hole is formed such that a surface in the thickness direction of the shielding plate facing the bottom surface of the case is recessed toward the inner side of the case in a state where the shielding plate is located on the bottom surface of the case. An industrial vehicle transmission characterized by the above . The case consists of a transmission case containing the clutch and a PTO case containing a PTO unit,
The suction part is located in the PTO case;
The transmission for an industrial vehicle according to claim 4 , wherein the shielding plate is located between the mission case and the PTO case. The through hole, the transmission of industrial vehicles according to 請 Motomeko 5 that passes communication between the inside of the inner and the PTO casing of the transmission case.