JP2002087222A - Fluid type retarder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To sufficiently shorten the length of an output shaft in a structure for installing a fluid type retarder on the output shaft of a transmission. SOLUTION: This fluid type retarder 2 is installed on the output shaft 28 of the transmission in a motive power transmission system including the transmission and a propeller shaft. The fluid type retarder 2 has an output flange 29, a stator 25, a rotor 24 and a hydraulic fluid supply device. The output flange 29 is relatively nonrotatably installed on an outer peripheral surface of the output shaft 28, and outputs motive power to the propeller shaft. The rotor 24 is relatively nonrotatably installed on an outer peripheral surface of the output flange 29. The stator 25 is oppositely arranged to the rotor 24. The hydraulic fluid supply device is a device for supplying a hydraulic fluid to a space between the rotor 24 and the stator 25.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a hydraulic retarder,
In particular, the present invention relates to a device attached to an output shaft of a transmission.

[0002]

2. Description of the Related Art Conventionally, a hydraulic retarder has been used as an auxiliary brake for a large vehicle such as a truck, a sightseeing bus, and a crane truck.

A hydraulic retarder is mounted, for example, on the output shaft of a transmission and hydrodynamically brakes rotation. Such a retarder is mainly composed of a pair of impellers housed in a working chamber and facing each other. Each impeller is used, for example, in a fluid coupling, and a plurality of radially extending blade members are arranged in an annular shape. One of the impellers is a rotating impeller (rotor) fixed to the rotating body, and the other is a fixed impeller (stator) non-rotatably fixed to the housing, and both constitute a torus-shaped retarder chamber. are doing. An oil sump that stores oil is disposed below the working chamber. When compressed air is sent from outside to the oil sump, the hydraulic oil in the oil sump is sent to the retarder chamber. Hydraulic oil flowing from the rotating impeller moves radially outward due to centrifugal force and flows in the rotating direction. Then, the operating oil collides with the blade member of the fixed impeller, flows in a direction opposite to the rotation direction of the rotating impeller, and returns to the rotating impeller. Hydraulic oil flowing from the fixed impeller impedes rotation of the rotating impeller and brakes the output shaft.

[0004]

A method of mounting a hydraulic retarder includes a propeller shaft intermediate type in which a hydraulic retarder is mounted between two propeller shafts, and a hydraulic retarder attached to a rear end of a transmission shaft. There is a direct transmission type.

In the latter direct transmission type, for example, a spline is formed on a rear end outer peripheral surface of the transmission shaft, and an output flange for outputting power to the propeller shaft is engaged with the spline. Further, the rotor of the hydraulic retarder is spline-engaged with the spline of the transmission shaft.

In the above structure, when the retarder chamber is filled with hydraulic oil, the braking force acts on the rotor, and then acts on the transmission output shaft, output flange, propeller shaft, axle, and tire in this order. To go.

Here, considering a structure in which only the output flange is mounted on the transmission shaft,
In order to mount a hydraulic retarder, it is necessary to extend the length of the transmission shaft for mounting the rotor. This necessitates modification of the transmission, which reduces the mountability, and may cause a problem due to the vibration of the drive system.

An object of the present invention is to suppress the length of the output shaft sufficiently short in a structure in which a fluid type retarder is mounted on the output shaft of a transmission.

[0009]

According to a first aspect of the present invention, in a power transmission system including a transmission and a propeller shaft, a hydraulic retarder is mounted on an output shaft of the transmission and is braked by hydraulic oil. The fluid type retarder includes an output flange, a fixed impeller, a rotary impeller, and a hydraulic oil supply device. The output flange is a member that is attached to the outer peripheral surface of the output shaft so as not to rotate relatively, and outputs power to the propeller shaft. The rotary impeller is attached to the outer peripheral surface of the output flange so as not to rotate relatively. The fixed impeller is arranged to face the rotary impeller. The hydraulic oil supply device is a device for supplying hydraulic oil between the rotary impeller and the fixed impeller.

In this fluid type retarder, since the rotary impeller is mounted on the outer peripheral surface of the output flange, there is no need to secure a mounting portion for the rotary impeller on the output shaft. That is, the output shaft can be kept sufficiently short.

[0011]

FIG. 1 is an overall schematic diagram of a retarder system 1 employing the present invention. Retarder system 1
Is mainly composed of a retarder 2 composed of two impellers and a control system 3 for controlling the operation of the retarder 2.

The retarder 2 is of a transmission direct mounting type which is attached to the rear end of the transmission output shaft 28. As shown in FIG. 2, the retarder 2 includes a working chamber 21 and an oil sump 2 provided below the working chamber 21.
And 2. The working chamber 21 is provided with an output flange 29 and an outer peripheral side of the output flange 29.
1 includes a housing 23 for securing one space, and a rotor 24 and a stator 25 disposed in the working chamber 21.

The output flange 29 is a member for transmitting power from the output shaft 28 of the transmission to a propeller shaft (not shown). The output flange 29 is a cylindrical member, and a first spline 29a that engages with a spline 28a formed on the outer peripheral surface of the output shaft 28 is formed on the inner peripheral surface of the output flange 29. Also, the output flange 29
A second spline 29b that engages with a spline formed on the inner peripheral surface of the rotor described later is formed on the outer peripheral surface of the rotor. The output flange 29 is axially sandwiched between the bearing 30 and a stop member 31 fixed to the output shaft 28, and cannot move in the axial direction with respect to the output shaft 28.

The housing 23 is provided on the outer peripheral surface of the output flange 29, and forms the annular working chamber 21 together with the outer peripheral surface of the output flange 29. Specifically, the housing 23 has a hollow annular shape in which only the inner peripheral side is open, and both ends of the inner peripheral edge are in contact with the outer peripheral surface of the output flange 29 via the oil seal 32 having a spring.

In the working chamber 21, a rotor 24 and a stator 25 are arranged to face each other. The rotor 24 (rotating impeller) and the stator 25 (fixed impeller) are impellers in which a plurality of blades extending radially are arranged in an annular shape. The stator 25 is non-rotatably fixed to the housing 23. The rotor 24 is disposed to face the stator 25 in the axial direction, and forms a torus-shaped retarder chamber 26.

A cylindrical hub 24a is provided on the inner peripheral portion of the rotor 24.
Is provided. A spline 24b that engages with a second spline 29b formed on the outer peripheral surface of the output flange 29 is formed on the inner peripheral surface of the hub 24a. Due to this spline engagement, the rotor 24 cannot rotate relative to the outer peripheral surface of the output flange 29. Since the hub 24a has a larger inner diameter than the conventional one, the force acting on the spline 24b can be reduced, so that the axial dimension of the hub 24a can be greatly reduced as compared with the conventional one. In particular,
The axial dimension of the hub 24a is 以下 or less of the axial dimension of the first spline 29a of the output flange 29, and is actually about 程度. As described above, the axial dimension of the hub 24a is greatly reduced as compared with the conventional case, and the overall size and weight are reduced.

The hub 24a of the rotor 24 is sandwiched between a snap ring 34 fixed to the outer peripheral surface of the output flange 29 and an axial surface 35 of the output flange 29 which faces one side (left side in FIG. 3) in the axial direction. It cannot move in the axial direction.

A predetermined amount of hydraulic oil is stored in the oil sump 22. One end of the first oil supply pipe 40 is open near the bottom of the oil sump 22, and the other end is open to the retarder chamber 26. In addition, the oil sump 22
An opening (not shown) through which compressed air sent from the control system 3 to be described later flows is formed in the upper part of the upper part.

An oil cooler (not shown) is provided on a side of the oil sump 22. The oil cooler collects hot oil between the rotor 24 and the stator 25, cools the oil, and returns the oil to the rotor 24 and the stator 25 again. An oil return pipe and a second oil supply pipe (not shown) are provided between the working chamber 21 and the oil cooler. The oil cooler circulates cooling water of the vehicle inside, and heat transferred from the oil to the cooling water is radiated to the atmosphere by a radiator of the vehicle.

Next, the control system 3 (pneumatic supply device)
Will be described. The control system 3 has an air tank 4 in which compressed air is filled, and a proportional solenoid valve 5 provided between the air tank 4 and the oil sump 22. A first pipe 1 is provided between the air tank 4 and the proportional solenoid valve 5.
0, the proportional solenoid valve 5 and the oil sump 22 are provided.
A second pipe 11 is provided between the first and second pipes. Second pipe 1
1 is connected to the opening of the oil sump 22. The proportional solenoid valve 5 can select whether to supply or shut off the compressed air from the air tank 4 into the oil sump 22, and can adjust the supply pressure in five stages when supplying air.

The control system 3 includes, for example, a CPU, RA
It further has a control unit 8 composed of a microcomputer having M, ROM and the like. Control unit 8
Is connected to a proportional solenoid valve 5. Further, a hand lever switch 9 provided in the driver's seat of the vehicle is connected to the control unit 8. The hand lever switch 9 is a device for the driver to determine the braking force of the retarder 2, and can shift the braking force in five stages. Further, a temperature sensor 12 provided on the cooling water outlet side of the oil cooler is connected to the control unit 8. Although not shown, the control unit 8 is connected to an overheat warning light provided in the driver's seat.

Next, the operation of the retarder system 1 will be described. In the non-braking state, no air pressure is supplied into the oil sump 22, and thus no hydraulic oil is supplied into the retarder chamber 26.

When detecting that the hand lever switch 9 is turned on, the control unit 8 sends a signal to the proportional solenoid valve 5 to supply the compressed air in the air tank 4 to the oil sump 22. The supply pressure of the proportional solenoid valve 5 at this time is determined by the hand lever switch 9.

When air pressure is supplied to the oil sump 22, the oil level is depressed, and hydraulic oil is supplied to the working chamber 21. As a result, the braking of the rotor 24 is started. When the retarder chamber is filled with hydraulic oil, the braking force is applied to the rotor 2
4 and then the output flange 29, the propeller shaft, the axle, and the tire.

The control unit 8 includes the temperature sensor 1
Then, it is determined whether or not the temperature of the cooling water has exceeded a predetermined temperature based on the signal from the control unit 2. If the water temperature exceeds a predetermined temperature, a warning light (not shown) in the driver's seat is turned on.

In this retarder 2, since the rotor 24 is mounted on the outer peripheral surface of the output flange 29, it is not necessary to secure a mounting portion for the rotor 24 on the output shaft 28 of the transmission. That is, the output shaft 28 can be kept sufficiently short. As a result, the modification of the transmission is not required, so that the mountability is improved, and further, the problem is hardly caused by the vibration of the drive system. Further, the hub 24a of the rotor 24 is reduced in size and weight. As described above, the cost can be significantly reduced as compared with the related art.

[0027]

In the hydraulic retarder according to the present invention, since the rotary impeller is mounted on the outer peripheral surface of the output flange, there is no need to secure a mounting portion for the rotary impeller on the output shaft of the transmission. That is, the output shaft can be kept sufficiently short.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a control configuration of a retarder according to an embodiment of the present invention.

FIG. 2 is a sectional view of a retarder.

FIG. 3 is a partially enlarged view of FIG. 2;

[Explanation of symbols]

 1 Retarder system 2 Retarder 24 Rotor 25 Stator 28 Transmission output shaft 29 Output flange

Claims (1)

[Claims] In a power transmission system including a transmission and a propeller shaft, a hydraulic retarder mounted on an output shaft of the transmission and braked by hydraulic oil, and mounted on an outer peripheral surface of the output shaft so as to be relatively non-rotatable. An output flange for outputting power to the propeller shaft, a rotary impeller attached to the outer peripheral surface of the output flange so as to be relatively non-rotatable, and a fixed impeller arranged to face the rotary impeller, A hydraulic oil supply device for supplying the hydraulic oil between the rotary impeller and the fixed impeller.