JP2532869B2 - Fluid type retarder with parking brake - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention relates to a retarder to be installed in an automobile, and in particular, it is made compact by being integrated with a parking brake.

[Prior Art] In an automobile such as a large-sized bus or truck that currently has a large load weight along with its own weight, when going down a long slope, there is a possibility that the heat generated on the friction surface will be large and the fade phenomenon will occur only with the regular foot brake. Therefore, the foot brake is assisted by using a reduction device such as an exhaust brake, an electromagnetic retarder, or a fluid retarder. Of these, a fluid retarder (hereinafter simply referred to as a retarder) forms a blade chamber (3) around a drive shaft (2) as shown in FIG. 2, and a rotor blade that rotates together with the drive shaft (2). A rotor blade (9) which rotates by supplying cooling oil (A) between the stator blade (8) fixed to the blade chamber (3) and the stator blade (8).
Causes a swirl in the cooling oil (A), converts the kinetic energy of rotation into heat and absorbs it, and has a good deceleration characteristic because the absorbed horsepower sharply increases as the rotation speed increases. . In the figure, (22) is a cooling oil tank,
(23) shows an oil pump that sends the cooling oil to the retarder. Such a retarder is usually incorporated in a transmission or a rear wheel drive device.

In addition, the brake for parking the car or fixing it on slopes is called a parking brake and is operated by a manual lever, and it is also used as a spare for a foot brake failure or a brake for an emergency stop, Generally, a duo servo type drum brake is used. This duo-servo type drum brake stops the rotation of the drum by expanding two half-moon shaped leading shoes with the brake lining attached to the inside of the rotating drum to the inner side of the drum by expanding inward. Compared to other drum brakes, it has a high effect.

For this reason, in medium- and heavy-duty trucks, the above-mentioned duo-servo type drum brake is attached to a transmission or a propeller shaft as a center brake for parking.

[Problems to be solved by the invention]

Due to the structure of the retarder, the duo-servo type drum brake dedicated to parking as described above was difficult to configure integrally, but there is a strong demand for compactness by integrating the two in terms of space saving. It was

Further, the retarding action of the retarder is adjusted by the flow rate of the cooling oil (A) in the blade chamber (3) as shown in FIG. 2, and is controlled by controlling the oil level in the blade chamber (3). Therefore, even when the operation of the retarder is stopped, that is, when the supply of the cooling oil into the blade case is stopped, some drag torque is generated due to the residual oil, which is a problem. In addition, the oil level control required expensive equipment.

[Means for solving problems]

As a result of various studies in view of the above, the present invention has developed a fluid type retarder with a parking brake that integrates a retarder and a parking brake and can eliminate drag torque of the retarder. A blade chamber of the fluid retarder is formed between the shafts or independently, and stator blades are integrally formed in the blade chamber. On the circular side plate of the brake drum fixed to the drive shaft, a clutch plate that rotates integrally with the rotor blades of the fluid retarder around the drive shaft or the propulsion shaft is provided as a pair, and further, a clutch plate facing the clutch plate is provided. A plate-shaped pressure plate is provided, the outer circumference of the plate is attached to the outer circumference of the circular side plate of the brake drum, which is extended to the retarder side, and the inner circumference is fixed to the outer ring of the clutch release bearing. The inner ring is attached to a ring-type clutch piston fixedly mounted on the backing plate, and the piston is operated to clamp the clutch plate between the pressure plate and the circular side plate of the brake drum to rotate the drive shaft or the propulsion shaft to rotate the rotor blade. The rotor blades are also made to self-pump.
A support shaft of a parking lever of a parking brake, which stops the rotation of a drive shaft or a propulsion shaft by internally pressing the brake shoe on the inner surface of the outer peripheral plate of the brake drum, is attached to the backing plate. Is.

[Action]

The backing plate forms the blade chamber of the retarder because a new member for the blade chamber is unnecessary and space is saved. The integral formation of the clutch plate and the rotor blades of the retarder means that the drive shaft and rotor blades are immediately cut off by disengaging the clutch when the retarder operation is stopped, so that the drive shaft receives the retarder braking. This is because the generation of drag torque can be eliminated altogether. Cooling oil is supplied / drained by the self-pumping action of the rotor blades, but clutch on / off and cooling oil supply / drain to / from the retarder may be performed independently, or they may be interlocked. . The control can be performed by using it as the service brake pedal and the control lever for the exhaust brake, which is very convenient in terms of usability.

Further, the reason why the parking lever for operating the brake shoe of the parking brake is attached to the backing plate forming the retarder is to integrate the retarder and the parking brake, and such a structure can make the whole compact.

Further, since these devices are provided outside the transmission or in an independent part, the clutch facing and the brake lining can be replaced easily.

〔Example〕

 The present invention will be described in more detail with reference to examples.

As shown in FIG. 1, the transmission case (1)
The side plate through which the drive shaft (2) penetrates is one side plate of the blade chamber (3) of the retarder, and the blade chamber (3) is attached to the transmission case (1) with the bolt (4). The blade chamber (3) is provided with a supply port (6) for supplying cooling oil from the lower part and a discharge port (7) for discharging cooling oil from the upper part, and the blade of the backing plate (5) A semicircular stator blade (8) is formed radially or curved around the drive shaft (2) on the side of the chamber (3), and further faces the stator blade (8) so as to face the drive shaft (2). A half-moon shaped rotor blade (9) that freely rotates around is also provided in a radial or curved shape.

One end of the rotor blade (9) on the drive shaft (2) side is extended from the backing plate (5) and the drive shaft (2) to the outside of the blade chamber while maintaining the airtightness of the blade chamber (3). A disc-shaped clutch plate (10) is raised at right angles to the shaft (2), and a circle of a brake drum (11) that rotates integrally with the drive shaft (2) outside the plate (10). Shape side plate (1
2) are installed oppositely, the circular outer periphery of the side plate (12) is extended to the transmission (1) side to form the outer peripheral plate (13) of the brake drum (11), and the clutch plate (10) is a circular side plate. A disc-shaped pressure plate (14) is attached to the outer peripheral plate (13) so as to be sandwiched between it and (12), and its inner periphery is fixed to the circular outer ring of the clutch release bearing (15).

Further, one end of the circular inner ring of the clutch release bearing (15) is fixed to a ring type clutch piston (16) fixedly mounted on the backing plate (5), and the piston (16) is operated to operate the pressure plate (14). Press the circular side plate (1) of the brake drum (11).
The clutch plate (10) is sandwiched between 2) and the pressure plate (14) so that the rotation of the drive shaft (2) is transmitted to the rotor blades (9) of the retarder.

Two half-moon shaped leading shoes (18) to which a brake lining (17) is attached are provided inside the outer peripheral plate (13) of the brake drum (11), and the leading shoe (18) is attached to the outer peripheral plate (13). ) To the inner expansion type to stop the rotation of the brake drum (11) to form a duo servo type drum brake, and the leading shoe (18)
The support shaft (21) of the parking lever (20) having the brake cam (19) for internally expanding the shaft is pivotally supported on the backing plate (5).

The fluid retarder with a parking brake as described above engages the clutch with the clutch piston (16) when decelerating the vehicle, transmits the rotation of the drive shaft (2) to the rotor blades (9) of the retarder, and immediately rotates the rotor blades (9). The rotation of the rotor blades (9), i.e. the drive shaft (2), can be damped by self-pumping or by supplying cooling oil into the blade chamber (3). When the retarder is disengaged, the clutch piston (16) is activated to disengage the clutch, so that the rotation of the drive shaft (2) is not subject to retarder braking instantaneously.
Therefore, the drag torque is also irrelevant. Response at the time of reacceleration is improved. When parking, the brake lining (17) is pressed against the outer peripheral plate (13) of the brake drum (11) by operating the manual parking lever (20) to stop the drive shaft (2).

〔The invention's effect〕

As described above, according to the present invention, since the fluid retarder and the parking brake are integrated with each other, the weight and the size can be reduced, the cost can be reduced, the maintenance is easy, and the performance of the fluid retarder is improved. It is effective.

[Brief description of drawings]

FIG. 1 is a side sectional view showing an embodiment of the present invention, and FIG. 2 is a side sectional view showing a fluid type retarder. 1 ... Transmission case or mounting member 2 ... Drive shaft 3 ... Blade chamber 4 ... Bolt 5 ... Backing plate 6 ... Supply port 7 ... Discharge port 8 ... Stator blade 9 ... Rotor blade 10 ... Clutch plate 11 …… Brake drum 12 …… Circular side plate 13 …… Outer peripheral plate 14 …… Pressure plate 15 …… Clutch release bearing 16 …… Ring type clutch piston 17 …… Brake lining 18 …… Leading shoe 19 …… Brake Cam 20 …… Parking lever 21 …… Support shaft 22 …… Cooling oil tank 23 …… Oil pump A …… Cooling oil

Claims (1)

(57) [Claims] 1. A backing plate in which a blade chamber of a fluid type retarder is formed around a drive shaft outside a transmission with a transmission case or between propulsion shafts or independently, and stator blades are integrally formed in the blade chamber. Provided integrally or separately with the transmission case or independently, and a clutch plate that rotates around the drive shaft or propulsion shaft integrally with the rotor blades of the above fluid retarder on the circular side plate of the brake drum fixed to the drive shaft. And further, a disc-shaped pressure plate is provided to face the clutch plate,
The outer periphery of the plate is attached to the outer periphery of the circular side plate of the brake drum, which is extended to the retarder side, and the inner periphery is fixed to one side of the clutch release bearing,
The other side of the bearing is attached to a ring-type or spot-type clutch piston fixed to the backing plate, and the piston is operated to hold the clutch plate between the pressure plate and the circular side plate of the brake drum to drive the drive shaft or propulsion. The rotation of the shaft is transmitted to the rotor blades, the brake shoe is internally expanded to press the inner surface of the outer peripheral plate of the brake drum, and the rotation of the drive shaft is stopped. A fluid retarder with a parking brake that is characterized by being installed.