JPH06229458A - Oil pressure circuit for lubrication in transmission device - Google Patents

Abstract

PURPOSE:To prevent a clutch from seizing in the transmission device of an industrial vehicle. CONSTITUTION:In an oil pressure circuit for lubrication, for supplying oil in a tank 20 to respective lubricating parts of a forward clutch 5 and a reverse clutch 7 provided in a transmission case 1 of a transmission device by a pump 22, a first switching valve 40 for lubrication, for supplying a large quantity of oil to the clutch side operated by contact, out of the forward clutch 5 and the reverse clutch 7, and also supplying a small quantity of oil to the other clutch side is provided. Even if a large quantity of frictional heat is generated in switching operation of the clutch, a large quantity of oil is supplied to the lubricating part of the clutch operated by contact, thereby the frictional heat is cooled by a large quantity of oil, so that the seizing of the clutch can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lubricating hydraulic circuit in a transmission provided in an industrial vehicle such as a forklift truck.

[0002]

2. Description of the Related Art Conventionally, as a transmission installed in an industrial vehicle such as a forklift truck, as shown in FIG. 1, a transmission case 1 is provided with an input shaft 2 connected to an engine, an intermediate shaft 3, and a drive shaft. Output shafts 4 connected to the wheel side are rotatably provided via bearings.
A wet multi-plate forward clutch 5 is attached to the input shaft 2.
And a forward gear 6 connected thereto and rotatable with respect to the input shaft 2, and a wet multi-plate reverse clutch 7 and connected therewith and rotatable with respect to the input shaft 2. A reverse gear 8 is provided, the forward gear 6 is engaged with an intermediate shaft first gear 9 fixed to the intermediate shaft 3, and the reverse gear 8 is fixed to the intermediate shaft 3. The two gears 10 are engaged with each other via a reversing gear 11. The intermediate shaft second gear 10 is engaged with the output shaft gear 12 fixed to the output shaft 4.

With such a configuration, the rotation on the engine side is first transmitted to the input shaft 2, and at the input shaft 2,
From the forward clutch 5 to the forward gear 6 and the intermediate shaft first gear 9
And the intermediate shaft 3 via the reverse clutch 7, or the reverse clutch 7 through the reverse gear 8, the reversing gear 11, and the intermediate shaft second gear 10 to the intermediate shaft 3. Then, from the intermediate shaft 3, the intermediate shaft second gear 10 and the output shaft gear 12
It is transmitted to the output shaft 4 via and, and is transmitted from the output shaft 4 to the drive wheels.

On the other hand, in an industrial vehicle, since the operation is switched to reverse while the vehicle is moving forward or forward while the vehicle is moving backward, a large amount of friction heat is generated in the forward clutch 5 or the reverse clutch 7. Since a large amount of frictional heat is generated in the forward clutch 5 or the reverse clutch 7 because the clutch is slipped and the half-clutch operation is performed to run the vehicle at a very low speed, the clutch is damaged due to seizure or wear of the clutch. Was occurring.

For this reason, in the transmission, a hydraulic circuit for lubrication is provided to supply the lubricating oil to the forward clutch 5 and the reverse clutch 7. The hydraulic circuit for lubrication has a pipeline connected to a pump 22 operated by a motor 21 operated by the driving force of the engine from the tank 20,
From there, the pipe is branched, and one of them is connected to the directional valve 25 via the inching valve 23 and the modulation valve 24, and the forward clutch 5 or the reverse clutch 7 is actuated from the directional valve 25. It is connected to the piston parts 5a, 7a for use with and the other is connected to the main relief valve 26. Then, the pipeline is branched at the end of the main relief valve 26 so that one is connected to the tank 20 via the torque converter inlet relief valve 27 and the other is connected to the torque converter 28, and the pipe is further connected from there. The path is branched so that one is connected to the tank 20 and the other is connected to the torque converter outlet relief valve 29. And the torque converter outlet relief valve 2
The pipe is branched at the end of 9 so that one is connected to the tank 20 via the lubrication relief valve 30 and the other is connected to the hole 31 formed inside the input shaft 2. There is. The hole 31 is opened in the longitudinal direction from one end face in the longitudinal direction of the input shaft 2, and its tip reaches near the reverse clutch 7 and, in the middle thereof, in the radial direction toward the forward clutch 5 and the reverse clutch 7. Input shaft 2
To the lubrication portion, which is the outer peripheral surface of each.

With such a configuration, the tank 20
The pressure oil inside the main relief valve 26, the torque converter 28, and the torque converter outlet relief valve 29 by the pump 22.
After that, the oil flows into the hole 31 in the input shaft 2 and is supplied to the forward clutch 5 and the reverse clutch 7, respectively, to lubricate the forward clutch 5 and the reverse clutch 7.

[0007]

Conventionally, in order to prevent the clutch from being damaged, a lubricating hydraulic circuit for supplying lubricating oil is provided to the lubricating portions of the forward clutch and the reverse clutch. In the lubrication hydraulic circuit, the oil discharged from the pump is divided into two parts and supplied to the lubrication part of the forward clutch and the lubrication part of the reverse clutch respectively, so that a certain amount is supplied to the lubrication part of each clutch. It was necessary to increase the size of the pump and increase the discharge amount from the pump. However, increasing the size of the pump causes a problem of increasing the size of the transmission as a whole, and the size of the pump also increases the size of the motor. However, there is a problem that the driving force for traveling the vehicle is greatly reduced. The object of the present invention is to solve these problems.

[0008]

DISCLOSURE OF THE INVENTION The present invention relates to a lubricating hydraulic circuit for supplying oil in a tank by a pump to each lubricating portion of each clutch provided in a transmission case of a transmission, to lubricate a clutch operating in contact. A large amount of oil is supplied to the parts and a switching valve for lubrication is provided to supply a small amount of oil to the lubricating parts of the other clutches.

[0009]

[Operation] The present invention provides a large amount of oil to the lubrication part of the clutch that operates by contact, and a small amount of oil to the lubrication part of the other clutch. It is possible to supply a large amount of oil to the clutch where the frictional heat is generated.

[0010]

[Example] A first example of the present invention will be described. As in the conventional transmission, as shown in FIG. 2, as a transmission, a transmission case 1 is provided with an input shaft 2, an intermediate shaft 3, and an output shaft 4, and a forward clutch 5 and a forward gear 6 are provided on the input shaft 2. A reverse clutch 7 and a reverse gear 8 are provided, an intermediate shaft first gear 9 and an intermediate shaft second gear 10 are fixed to the intermediate shaft 3, and an output shaft gear 1 is attached to the output shaft 4.
2 is fixed, the engine side rotation is transmitted to the input shaft 2, and in the input shaft 2, from the forward clutch 5 to the intermediate shaft 3 via the forward gear 6 and the intermediate shaft first gear 9, or Reverse clutch 7 to reverse gear 8 and reversing gear 1
1 and the intermediate shaft second gear 10 and transmitted to the intermediate shaft 3 by either one of the intermediate shaft 3 and the intermediate shaft second gear 10.
Is transmitted to the output shaft 4 via the output shaft gear 12, and is transmitted from the output shaft 4 to the drive wheels.

In the above transmission, the lubricating hydraulic circuit for supplying lubricating oil to the lubricating portions of the forward clutch 5 and the reverse clutch 7 is driven by the motor 21 driven by the engine driving force from the tank 20. Pump 2 that works
Connect the pipe line to 2, branch the pipe line at the end of the pump 22,
One is an inching valve 23 and a modulating valve 24.
Is connected to the directional valve 25 via the directional valve 25, and the piston portion 5a for operating the forward clutch 5 or the reverse clutch 7 is connected from the directional valve 25.
7a and the other one is the main relief valve 2
Connect to 6. Then, the pipeline is branched at the tip of the main relief valve 26, one of which is connected to the tank 20 via the torque converter inlet relief valve 27, and the other of which is connected to the torque converter 28, and the pipeline is branched at the tip of the torque converter 28. Then, one is connected to the tank 20 and the other is connected to the torque converter outlet relief valve 29. Then, the pipeline is branched at the tip of the torque converter outlet release valve 29, one of which is connected to the tank 20 through the lubrication relief valve 30 and the other of which is connected to the first lubrication switching valve 40 which is a lubrication switching valve. However, in connecting the first switching valve for lubrication 40 and the pipeline, the pipeline is branched before the connection, and one is directly connected to the first inlet port a of the first switching valve for lubrication 40 and the other is connected. The second inlet port b of the first lubrication switching valve 40 is connected via the orifice 41.

The lubricating first switching valve 40 has a first inlet port a, a second inlet port b, a first outlet port c and a second outlet port d, and is located at the left position A and the center. It is designed to switch between position B and right position C. At left position A, the first inlet port a is connected to the first outlet port c, and the second inlet port b is connected to the second outlet port d. At position B, the first inlet port a and the second inlet port b
And the first outlet port c and the second outlet port d are all connected, and at the right position C, the first inlet port a is connected to the second outlet port d, and the second inlet port b is connected to the first outlet port c. .

A pipe line is connected from the first outlet port c of the first lubrication switching valve 40 to a forward movement hole portion 42 formed inside the input shaft 2, and the forward movement hole portion 42 receives an input. The shaft 2 opens in the longitudinal direction from one end face in the longitudinal direction to the vicinity of the forward clutch 5, and at its tip, it opens radially toward the forward clutch 5 to the lubrication portion on the outer peripheral surface of the input shaft 2. On the other hand, a pipe line is connected from the second outlet port d of the first lubrication switching valve 40 to a backward movement hole portion 43 formed inside the input shaft 2, and the backward movement hole portion 43 has a longitudinal direction of the input shaft 2. Open in the longitudinal direction from one end face to the vicinity of the reverse clutch 7,
At the tip thereof, a radial direction is opened toward the reverse clutch 7 to the lubrication portion of the outer peripheral surface of the input shaft 2, and a sealing body 44 is inserted into one longitudinal end of the reverse hole 43 to insert a reverse hole. The one end of 43 is sealed, and the pipe line from the first switching valve for lubrication 40 is connected to the backward hole 43 in the radial direction, so that the forward hole 42 formed in the input shaft 2 is formed. And the reverse hole portion 43 do not communicate with each other. In addition, in the advance hole portion 42, while opening toward the outer peripheral surface of the input shaft 2 in the radial direction toward the advance gear 6,
The backward movement hole portion 43 is configured to open radially toward the backward movement gear 8 to the outer peripheral surface of the input shaft 2.

Further, in the first switching valve 40 for lubrication and the directional valve 25, each is electrically connected to a controller 45, and the controller 45 is electrically connected to a switching lever 46 for switching between forward and reverse. The switching operation of the first switching valve 40 for lubrication and the directional valve 25 is controlled based on a signal from the switching lever 46.

In the present embodiment, the switching operation of the first switching valve 40 for lubrication and the directional valve 25 is controlled by using the controller 45. The first switching valve 40 and the directional valve 25 may be mechanically connected and the switching lever 46 may directly perform the switching operation.

Next, the operating state of the lubricating first switching valve 40 will be described. The pressure oil in the tank 20 is passed by the pump 22 through the main relief valve 26, the torque converter 28, the torque converter outlet relief valve 29, and the first switching valve 4 for lubrication.
It flows to 0. At this time, it branches before the first switching valve 40 for lubrication and flows to the first inlet port a and the second inlet port b, but on the second inlet port b side, the flow rate of the pressure oil is reduced by the orifice 41, and The flow rate of the pressure oil on the side of the first inlet port a is increased by the amount reduced on the side of the second inlet port b. Then, in the first switching valve 40 for lubrication, in the case of the left position A, a large amount of pressure oil is flown from the first inlet port a to the first outlet port c, flows through the pipeline and flows into the forward hole portion 42, A large amount of pressure oil is supplied to the lubrication portion of the forward clutch 5, and a small amount of pressure oil is caused to flow from the second inlet port b to the second outlet port d, and then flows through the pipe line into the backward movement hole portion 43. 7
Supply a small amount of pressure oil to the lubrication part. Further, in the lubricating first switching valve 40, in the case of the middle position B, the same amount of pressure oil is applied from the first inlet port a and the second inlet port c to the first outlet port c and the second outlet port d. To flow into the forward hole portion 42 and the reverse hole portion 43 along the respective pipelines, and the same amount of pressure oil is supplied to the lubricating portion of the forward clutch 5 and the lubricating portion of the reverse clutch 7. Further, in the first switching valve for lubrication 40, in the case of the right position C, the first inlet port a
A large amount of pressure oil is flowed from the second outlet port d to the second hole 43 through the pipeline, and a large amount of pressure oil is supplied to the lubrication portion of the reverse clutch 7 while the second inlet port b is used. A small amount of pressure oil is caused to flow through the one outlet port c, flows along the pipeline and flows into the forward movement hole portion 42, and a small amount of pressure oil is supplied to the lubrication portion of the forward clutch 5.

With this configuration, when the vehicle is traveling, when the vehicle is operated to switch to the reverse while the vehicle is moving forward, or when the vehicle is moving to the vehicle while the vehicle is moving backward, the clutch is slipped when the vehicle is moving forward or backward and the vehicle is moved at a very low speed. In the forward clutch 5 or the reverse clutch 7, a large amount of frictional heat is generated by the above operation in the forward clutch 5 or the reverse clutch 7 when a half-clutch operation is performed. By supplying a small amount of lubricating oil to the lubricating portion of the other clutch to cool the clutch in which frictional heat is generated, seizure and wear of the clutch due to frictional heat are reduced, It is possible to prevent breakage, and it is no longer necessary to upsize the pump 22 to supply a large amount of lubricating oil to the clutch as in the conventional case. Together to prevent, eliminate a decrease in the driving force for the vehicle running in the engine due to increase in the size of the pump 22.

Next, a second embodiment according to the present invention will be described. As a transmission, as shown in FIG. 3, a transmission case 1 is provided with an input shaft 2, an intermediate shaft 3, and an output shaft 4,
The input shaft 2 is provided with a reverse first speed clutch 50 and a reverse first speed gear 51, a reverse second speed clutch 52 and a reverse second speed gear 53, and an input shaft gear 54 is fixed. . Further, the intermediate shaft 3 is provided with a forward first speed clutch 55 and a forward first speed gear 56, a forward second speed clutch 57 and a forward second speed gear 58, and is further connected to the input shaft gear 54. The mating intermediate shaft gear 59 is fixed. Further, the output shaft 4 is provided with the reverse gear 1 gear 51.
Output shaft first gear 60 that engages with the forward first speed gear 56
And the output shaft second gear 61 that engages with the reverse second speed gear 53 and the forward second speed gear 58 is fixed.

With this configuration, the rotation on the engine side is transmitted to the input shaft 2, and in the input shaft 2, the reverse first speed clutch 50 through the reverse first speed gear 51 and the output shaft first gear 60. To the output shaft 4 or from the reverse 2nd speed clutch 52 to the output shaft 4 via the reverse 2nd speed gear 53 and the output shaft second gear 61, or from the input shaft gear 54 to the intermediate shaft gear 59. In the intermediate shaft 3, it is transmitted from the forward first speed clutch 55 to the output shaft 4 via the forward first speed gear 56 and the output shaft first gear 60, or the forward second speed clutch 57. Is transmitted to the output shaft 4 via the second forward speed gear 58 and the output shaft second gear 61, and is transmitted from the output shaft 4 to the drive wheels.

The reverse first speed clutch 50 and the reverse 2
The lubricating hydraulic circuit that supplies lubricating oil to the lubricating portions of the speed clutch 52, the forward first speed clutch 55, and the forward second speed clutch 57 is the first embodiment from the tank 20 to the first lubricating switching valve 40. The configuration is similar to the example, and the first switching valve for lubrication 4
The second switching valve 62 for lubricating the pipe from the first outlet port c of 0.
At the same time, the pipe line is connected to the third lubrication switching valve 63 from the second outlet port d of the first lubrication switching valve 40. The configuration of the second lubrication switching valve 62 and the third lubrication switching valve 63, and the connection of the second lubrication switching valve 62 and the pipe or the third lubrication switching valve 63 and the pipe are the same as those of the first lubrication valve. It has the same configuration as the switching valve 40.

The forward movement 1 formed inside the intermediate shaft 3 from the first outlet port c of the second lubricating switching valve 62.
A pipe line is connected to the speed hole portion 64, and the forward speed 1 hole 64 is provided from the longitudinal first end surface of the intermediate shaft 3 to the forward speed clutch 55.
It opens to the vicinity in the longitudinal direction, and at its tip, it opens radially toward the first forward speed clutch 55 to the lubrication portion on the outer peripheral surface of the intermediate shaft 3. On the other hand, a pipe line is connected from the second outlet port d of the second lubrication switching valve 62 to the second forward speed hole 65 formed inside the intermediate shaft 3, and the second forward speed hole 65 is an intermediate hole. The shaft 3 opens longitudinally from one end face in the longitudinal direction to the vicinity of the second forward speed clutch 57, and the intermediate shaft 3 radially extends toward the second forward speed clutch 57 at its tip.
To the lubrication part on the outer peripheral surface of. Also, the advance 1
A sealing body 66 is inserted into one end of the speed hole portion 64 in the longitudinal direction to seal one end of the forward first speed hole portion 64, and the conduit from the second lubricating switching valve 62 is connected to the forward first speed hole. By connecting to the 64 part in the radial direction, the forward movement 1 formed on the intermediate shaft 3
The speed hole portion 64 and the forward second speed hole portion 65 do not communicate with each other.

A pipe line is connected from the first outlet port c of the third switching valve for lubrication 63 to the reverse gear 1 hole 67 formed inside the input shaft 2, and the reverse gear 1 hole is formed. 67 is opened in the longitudinal direction from one longitudinal end surface of the input shaft 2 to the vicinity of the reverse first speed clutch 50, and at the tip thereof, radially toward the reverse first speed clutch 50 to the lubrication portion of the outer peripheral surface of the input shaft 2. It is open. On the other hand, the lubricating third switching valve 6
The second reverse speed hole 68 formed in the input shaft 2 through the second outlet port 3 of FIG. 3 is connected to a pipe line, and the second reverse speed hole 68 extends backward from one longitudinal end surface of the input shaft 2. It opens in the longitudinal direction up to the vicinity of the second speed clutch 52, and at the tip thereof, it opens radially toward the reverse second speed clutch 52 to the lubrication portion of the outer peripheral surface of the input shaft 2, and the reverse first speed hole portion 67. Insert the sealing body 69 at one longitudinal end of the
One end of the speed hole 67 is sealed, and the third switching valve for lubrication 6
By connecting the conduit from 3 to the reverse gear 1 hole 67 in the radial direction, the reverse gear 1 hole 67 and the reverse gear 2 hole 68 formed on the input shaft 2 do not communicate with each other. The configuration.

The first switching valve for lubrication 40, the second switching valve for lubrication 62, and the third switching valve for lubrication 63 are electrically connected to the controller 45, as in the first embodiment. The switching operation is controlled by 45.

With this structure, the clutch switching operation and the half-clutch operation are performed in the forward first speed clutch 55, the forward second speed clutch 57, the reverse first speed clutch 50, and the reverse second speed clutch 52. In this case, a large amount of lubricating oil is supplied to the lubrication part of the clutch that generates a large amount of frictional heat by the above-mentioned operation, and a small amount of lubricating oil is supplied to the lubrication part of the other clutch to reduce the frictional heat. By cooling the generated clutch, like the first embodiment, seizure and wear of the clutch due to frictional heat can be reduced, damage of the clutch can be prevented, and it is not necessary to upsize the pump 22. , While preventing an increase in the size of the entire transmission,
Elimination of a reduction in the driving force for running the vehicle of the engine due to the upsizing of the pump 22.

[0025]

EFFECTS OF THE INVENTION A lubricating switching valve is provided which supplies a large amount of oil to the lubricating portion of a clutch that operates in contact and supplies a small amount of oil to the lubricating portion of another clutch. In particular, a large amount of oil is supplied to the lubrication part of the clutch where a large amount of frictional heat is generated when switching the clutch, etc.
The clutch can be cooled, seizure and wear of the clutch due to frictional heat can be reduced, and damage to the clutch can be prevented. Further, since a large amount of lubricating oil can be supplied without increasing the size of the pump, it is possible to prevent the size of the entire transmission from increasing due to the size of the pump.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a lubricating hydraulic circuit in a conventional transmission.

FIG. 2 is an explanatory diagram of a lubricating hydraulic circuit in the transmission of the first embodiment according to the present invention.

FIG. 3 is an explanatory diagram of a lubricating hydraulic circuit in the transmission of the second embodiment according to the present invention.

[Explanation of symbols]

1 ... Mission case, 2 ... Input shaft, 3 ... Intermediate shaft, 4 ...
Output shaft, 5 ... Forward clutch, 6 ... Forward gear, 7 ... Reverse clutch, 8 ... Reverse gear, 9 ... Intermediate shaft first gear,
10 ... Intermediate shaft second gear, 11 ... Inversion gear, 12 ... Output shaft gear, 20 ... Tank, 21 ... Motor, 22 ... Pump,
23 ... Inching valve, 24 ... Modulate valve,
25 ... Directional valve, 26 ... Main relief valve, 27 ... Torque converter inlet relief valve, 28 ... Torque converter, 29 ... Torque converter outlet relief valve, 30 ... Lubrication relief valve, 31 ... Hole portion, 40 ... Lubrication first switching valve , 41 ... Orifice, 42 ... Forward hole, 43 ... Reverse hole, 44 ... Sealing body, 45 ... Controller, 46 ...
Switching lever, 50 ... 1st reverse clutch, 51 ... 1 reverse
High speed gear, 52 ... Reverse 2nd speed clutch, 53 ... Reverse 2nd speed gear, 54 ... Input shaft gear, 55 ... Forward 1st speed clutch, 56 ... Forward 1st speed gear, 57 ... Forward 2nd speed clutch, 58 ... Forward second speed gear, 59 ... Intermediate shaft gear, 60 ...
Output shaft first gear, 61 ... Output shaft second gear, 62 ... Lubrication second switching valve, 63 ... Lubrication third switching valve, 64 ... Forward first speed hole portion, 65 ... Forward second speed hole portion, 66 ... Sealing body, 67 ...
1st reverse speed hole, 68 ... 2nd reverse speed hole, 69 ... Sealing body.

Claims (1)

[Claims] 1. In a lubrication hydraulic circuit for supplying oil in a tank 20 by a pump 22 to each lubrication part of each clutch provided in a transmission case 1 of a transmission, a large amount of lubrication part of a clutch operated in contact is provided. A lubrication hydraulic circuit in a transmission, comprising a lubrication switching valve that supplies oil and supplies a small amount of oil to the lubrication portion of another clutch.