JP2547005Y2 - Fluid retarder controller - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic retarder control device.

[0002]

2. Description of the Related Art There are known large vehicles such as trucks and buses equipped with a hydraulic retarder device. The fluid type retarder device generates braking torque when descending a slope, decelerating from a high speed, or the like, prevents fade due to a rise in brake temperature, and improves vehicle safety and durability of friction materials. The fluid type retarder device includes, for example, a rotor that can be fixed to a rotating shaft that rotates together with wheels such as a propeller shaft, and a stator that is fixed to the vehicle body so as not to rotate, and operates in a retarder chamber that houses the stator and the rotor. Using a fluid retarder filled with liquid,
The rotor is connected and fixed to the rotating shaft side by a clutch device, and a braking torque is generated by friction and collision loss of the working liquid between the stator and the rotor.

[0003] As a conventional fluid type retarder control device, a device having a liquid temperature detecting means is known. This type of liquid temperature detecting means is provided in a working liquid cooler provided in a circuit connecting the working liquid inlet and the working liquid outlet of the fluid type retarder, and detects the working liquid returning to the working liquid cooler. Monitors the temperature and detects when the temperature of the working fluid may rise abnormally (overheat),
Deactivate the hydraulic retarder.

However, such a conventional fluid type retarder apparatus has a structure in which a single liquid temperature detecting means is provided in the cooler for working liquid, so that the liquid temperature detecting means fails, or the liquid temperature detecting means fails. When the detection means is covered by foreign matter and malfunctions, abnormal temperature rise of the working fluid causes damage to the rubber seal, which not only causes a failure of the fluid retarder, but also causes a fire. Even fear of becoming.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of such a conventional technical problem, and its structure is provided on a rotating shaft that rotates together with wheels, and is always filled with a working liquid. And a hydraulic retarder having a rotor and a non-rotating stator, driven by a driving device,
A clutch device that connects or disconnects the rotor and the rotating shaft, a closed circuit that connects between a working liquid inlet and a working liquid outlet of the hydraulic retarder through a working liquid cooler,
An air-liquid converter for applying air pressure to the working liquid in the closed circuit, a pressure reducing valve capable of switching at least a high pressure and a low pressure of air supplied from a pressure air source to the air-liquid converter, and the fluid type retarder First liquid temperature detecting means provided on the outer peripheral half of the liquid crystal device and detecting a first predetermined temperature of the working liquid;
A second liquid temperature detecting means provided in the working liquid cooler, the second liquid temperature detecting means detecting a second predetermined temperature of the working liquid lower than the temperature detected by the first liquid temperature detecting means in accordance with a temperature decrease accompanying the flow of the working liquid; And when one of the liquid temperature detecting means detects that the working liquid has risen to one of the predetermined temperatures, the driving device is driven to disconnect the clutch device. This is a fluid type retarder control device.

[Action]

[0006] When the clutch device is connected by the driving device while the vehicle is running, the rotor starts rotating integrally with the rotating shaft, and the fluid type retarder operates. Then, the pressure of the air supplied from the pressurized air source to the air-liquid converter is switched to a high pressure or a low pressure by a pressure reducing valve, and a predetermined air pressure is applied to the working liquid in the closed circuit, thereby responding to this pressure. A braking torque is generated. That is, in a circulating state in which the working liquid also serving as cooling flows in from the working liquid inlet and flows out from the working liquid outlet by the self-pumping action of the rotor, the working liquid to which kinetic energy is given by stirring of the rotor is used. The braking action is obtained while colliding with the stator and being transmitted to the working liquid as heat.

The temperature of the working liquid rises with the operation of the fluid type retarder, and the first or second predetermined temperature (for example, about 130 to 150 ° C.) of the working liquid is changed to the first liquid temperature detecting means or the second liquid. If the temperature is detected by one of the temperature detecting means, the first switching valve is switched to disconnect the clutch device. As a result, the operation of the hydraulic retarder is stopped, so that troubles caused by overheating of the hydraulic retarder, in particular, fire are prevented. In this way, the first or second liquid temperature detecting means or the second liquid temperature detecting means in which the relatively high first or second predetermined temperature of the working liquid is slightly different in detection temperature according to the temperature decrease accompanying the flow of the working liquid. Since the first liquid temperature is detected by either one of them, the first liquid temperature detecting means is provided on the outer peripheral half of the fluid type retarder, and the temperature of the working liquid in the fluid type retarder in the agitated state by the rotor is provided. In combination with the relatively accurate detection, the possibility of overheating of the hydraulic retarder can be accurately detected.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 show one embodiment of the present invention.
As shown in FIG. 1, the hydraulic retarder includes a hydraulic retarder 11, a clutch device 13, and a pneumatic cylinder device 17.
The main components are a hydraulic retarder unit 1, a cooler / pump unit 2, a pressure control device 3, a pressure air source 4, and a retarder switch 5 including The hydraulic retarder 11
A non-rotating case 11c is fixed to a vehicle body-side member such as a side member of a frame (not shown) or a transmission rear cover. A rotating shaft 10 having one end connected to a transmission output shaft or the like is provided at the center of the case 11c. ,
It penetrates freely and in a liquid-tight manner with an appropriate seal member and bearing interposed. The other end of the rotating shaft 10 is connected to wheels via a propeller shaft (not shown) or the like, and rotates together with the wheels.

In this manner, the retarder chamber 12 which is partitioned around the rotary shaft 10 by the case 11c and is always filled with the working liquid (oil or water) is liquid-tightly defined. In the retarder chamber 12, there is provided a stator 15 having radial blades formed around the rotation shaft 10, and has radial blades formed around the rotation shaft 10, and rotates in opposition to the stator 15. A rotor 16 that can be fixed to the member on the shaft 10 side so as not to rotate relatively is provided. Stator 15
Is integrally formed with the case 11c, and is fixed to the vehicle body side member so as to be substantially non-rotatable.

The case 11c has a retarder chamber 12 therein.
The working liquid inlet 11a is provided at the center of the
The working liquid outlet 11 is located at the outer periphery of the retarder chamber 12.
b is provided.

Further, a rotating shaft 1 is provided on an inner peripheral portion of the rotor 16.
A wet multi-plate clutch device 13 capable of connecting or disconnecting the 0-side member and the rotor 16 is provided. The clutch device 13
A plurality of annular pressure plates 14, a first bearing 13 fixed to the rotor 16 and mounted on the case 11c;
a supporting member 19 which is rotatably supported via a, and spline-connects an appropriate pressure plate 14 to movably support the central pressure in a central axis direction, and a movable pressure plate 14 located at one end. A second bearing 13b rotatably supported.

The clutch device 13 is provided with a pneumatic cylinder device 17 as a driving device. The pneumatic cylinder device 17 includes a pressure chamber 17c defined by a diaphragm 17a, a diaphragm 17a and a second bearing 13b.
And a connecting member 17b for connecting On the other hand, a plurality of clutch plates 18 are spline-coupled to the rotating shaft 10 so as to be movable in the axial direction, and each pressure plate 1
It is sandwiched between four.

When the compressed air from the compressed air source 4 is supplied to the pressure chamber 17c of the pneumatic cylinder device 17 through the first switching valve 31, which will be described later, the diaphragm 17a, the connecting member 17b and the second bearing 13b are provided. The movable pressure plate 14 located at one end is pushed in through the clutch plate 1 and rotates integrally with the rotating shaft 10.
Since each pressure plate 14 is pressed against 8,
The clutch device 13 is connected. Thereby, Case 1
Since the cylindrical support member 19 rotatably supported by 1c via the first bearing 13a rotates, the rotor 16 integrated with the support member 19 rotates integrally with the rotary shaft 10. Then, the kinetic energy of the liquid filled between the rotor 16 and the stator 15 is converted into thermal energy to generate a braking torque.

The pressure control device 3 includes a first switching valve 31
And a second switching valve 32. The first switching valve 31 is interposed between the pressure air source 4 and the pressure chamber 17c of the pneumatic cylinder device 17 with a pressure reducing valve 35, and supplies the pressure air from the pressure air source 4 to the pressure chamber 17c. , A position for draining the pressure chamber 17c. The second switching valve 32 is interposed between the pressure air source 4 and an air chamber 25d of the air-liquid conversion device 25 described later via a pair of pressure reducing valves 33 and 34 connected in parallel on the upstream side, It has a low pressure position c and a high pressure position d for supplying the pressurized air from the pressurized air source 4 to the air chamber 25d via one of the pressure reducing valves 33 or 34.

Since the pair of pressure reducing valves 33 and 34 are set to different pressures, the pressure of the pressure air source 4 is reduced by the pressure of the pressure air source 4 depending on the normal position c of the second switching valve 32. The pressure is adjusted to a relatively low set pressure by the valve 33 and supplied to the air chamber 25d of the air-liquid conversion device 25. The second switching valve 32 is switched to the d position, whereby the pressure air of the pressure air source 4 is changed. Is reduced to a relatively high set pressure by the other pressure reducing valve 34 and supplied to the air chamber 25 d of the air-liquid conversion device 25. Thus, the pair of pressure reducing valves 33 and 34 provided with the second switching valve 32 function as pressure reducing valves capable of switching the pressure of the air supplied from the pressurized air source 4 to the air-liquid conversion device 25 to at least high pressure and low pressure. I do. The pressure reducing valves 33 and 34 can relieve the pressure on the secondary side, that is, on the air chamber 25 d side of the air-liquid converter 25.

The first switching valve 31 and the second
The switching valve 32 is connected to the retarder switch 5,
The two valves 31 or 32 are selected and switched. On the other hand, the working liquid inlet 11a provided in the case 11c
Is connected to the working liquid outlet 11b provided in the case 11c via the closed circuit 21 and the cooler / pump unit 2. That is, in the closed circuit 21, the working liquid inlet 11a
A pump 22 for circulating the working liquid sequentially from the side and a cooler 23 for the working liquid are connected. The pump 22 is rotationally driven by an electric motor 22a, and the working liquid cooler 23 is air-cooled by a fan 23a.

In addition, an air-liquid for applying air pressure to an appropriate portion of the closed circuit 21 (one end of the working liquid cooler 23 in the illustrated embodiment) and to the working liquid of the fluid type retarder 11. The conversion device 25 is connected via a pipe 28. The air-liquid converter 25 includes an air-liquid converter main body 25.
The inside of a is divided into a working liquid chamber 25c for storing a working liquid and an air chamber 25d by a rubber film 25b which is an airtight and easily deformable flexible film. This working liquid chamber 25c is always connected to the closed circuit 21, and the air chamber 25c
d is connected to the pressure air source 4 via one of the above-described second switching valve 32 and a pair of pressure reducing valves 33 and 34 connected in parallel to the upstream side, and pressurized air of a predetermined pressure is supplied to the air chamber 25d. Therefore, the pressure of the working liquid of the closed circuit 21 and thus of the hydraulic retarder 11 can be adjusted. The working liquid chamber 25c also functions as a working liquid reservoir.

A working liquid reservoir 27 is connected to the working liquid chamber 25c via a manual switching valve 26.
By the switching operation of the manual switching valve 26, the working liquid in the working liquid reservoir 27 can be supplied to the working liquid chamber 25c of the air-liquid conversion device 25.

A first liquid temperature detecting means 41 which is provided on the outer peripheral half of the fluid type retarder 11 and comprises a switch for detecting a relatively high first predetermined temperature (for example, 150 ° C.) of the working liquid; Is slightly lower than the temperature detected by the first liquid temperature detecting means 41 (10 to 20).
A second liquid temperature detecting means 42 comprising a switch for detecting a second predetermined temperature of the working liquid which is low. First
The reason that the liquid temperature detecting means 41 is provided in the outer half of the fluid type retarder 11 is that the inner half of the fluid type retarder 11 in the agitated state by the rotor 16 is liable to generate cavitation, and the working liquid in the agitated state. This is because it is difficult to accurately grasp the temperature of the air. Further, the temperature detected by the second liquid temperature detecting means 42 is slightly smaller than the temperature detected by the first liquid temperature detecting means 41 (10
-20 ° C), but this is because the retarder room 1
This is because the temperature drop of the working liquid from flowing out of the working liquid outlet 11b to flowing through the closed circuit 21 and flowing into the working liquid cooler 23 was considered. The first predetermined temperature (for example, 150 ° C.) is set slightly lower than the actual temperature at which overheating occurs so that an instantaneous temperature rise can be detected.

The first liquid temperature detecting means 41 or the second liquid temperature detecting means 42 determines whether the operating liquid is either the first liquid or the second liquid.
When either one of the liquid temperature detecting means 41 or 42 detects that the temperature has risen to the predetermined temperature, the pneumatic cylinder device 17 is drained to drive the device to return, and the clutch device 13 is disconnected. I do. The return driving of the pneumatic cylinder device 17 is actually performed by the switch 43.
Is cut off to switch the first switching valve 31 to the position a, and the diaphragm 17a and the connecting member 17b are returned by a spring (not shown).

Further, there is provided a third liquid temperature detecting means 44 comprising a switch for detecting an intermediate third predetermined temperature (for example, 120 ° C.) of the working liquid. The third liquid temperature detecting means 44 is usually provided in the fluid type retarder 11, but may be provided in the closed circuit 21 such as the working liquid cooler 23. When the third liquid temperature detecting means 44 detects that the working liquid has risen to the third predetermined temperature, the third liquid temperature detecting means 44 sets the second switching valve 32 to c.
Then, the pressure of the air supplied to the air-liquid converter 25 is switched to the low pressure side. Actually, the switch 45 is turned off, the second switching valve 32 is set to the position c, and the switching to the position d is prohibited.

Further, there is provided a fourth liquid temperature detecting means 46 for detecting a relatively low fourth predetermined temperature (for example, 80 ° C.) of the working liquid. The fourth liquid temperature detecting means 46 is usually provided in the working liquid cooler 23, but may be provided in the hydraulic retarder 11 or the closed circuit 21.

The first to fourth liquid temperature detecting means 41,
Reference numerals 42, 44, and 46 are incorporated in the control circuit shown in FIG. First, the power supply 50 includes an exhaust brake switch 51 for operating the exhaust brake 54, an accelerator switch 52 that closes when the accelerator pedal is not depressed,
A clutch switch 57 that closes when the clutch pedal for connection and disconnection of the driving force for driving is not depressed, an antilock switch 53 that closes when the antilock brake system is inactive, and an exhaust brake 54 are connected in series. Further, the power supply 50 is connected to a pressure switch 55 which is closed by the pressure drop of the pressurized air source 4 and an alarm lamp 56 for warning the pressure drop.

The retarder switch 5 is connected between the exhaust brake switch 51 and the accelerator switch 52,
It has each switching position of position, position 2, and position 3. The first position is a position where the exhaust brake switch 51 is closed and only the exhaust brake 54 is operated, and the second position has the second switching valve 32 take the low pressure position c and is relatively low via one pressure reducing valve 33. The pressure is applied to the air chamber 25d of the air-liquid conversion device 25. The third position causes the second switching valve 32 to take the high pressure position d, and the other pressure reducing valve 3
4 is a position where a relatively high pressure is applied to the air chamber 25 d of the air-liquid conversion device 25 via the air pressure chamber 4. In addition, these two positions and three
In the position, the clutch device 13 is connected and driven by the pneumatic cylinder device 17.

A signal indicating that the retarder switch 5 is in the second or third position is input to the four input terminals of the first AND circuit 60 via the circuit 75 via the exhaust brake switch 5.
1. The signal that the accelerator switch 52, the clutch switch 57, and the antilock switch 53 are all closed is inverted through a circuit 76, and the signal that the pressure switch 55 is opened is inverted through a circuit 77 having a knot circuit 61. And the first liquid temperature detecting means 41 or the second liquid temperature detecting means 4
A signal when at least one of the two has detected the first or second predetermined temperature is inverted via a circuit 78 including a knot circuit 62 and connected to each other. For this reason,
A pair of first liquid temperature detecting means 41 and second liquid temperature detecting means 42
Are connected to the input terminals of the OR circuit 64, respectively, and the output terminal of the OR circuit 64 is connected to the circuit 78. The output terminal of the first AND circuit 60 is connected to the switch 43 via a circuit 84, and the switch 43 is closed by an output signal from the first AND circuit 60. By the closing operation of the switch 43, the operation of the first switching valve 31 by the retarder switch 5 is ensured, and by the opening operation, a is independent of the switching position of the retarder switch 5a.
Switch to position.

When at least one of the first liquid temperature detecting means 41 and the second liquid temperature detecting means 42 detects the first or second predetermined temperature, the buzzer 65 emits an alarm sound. ing. Also, the exhaust brake switch 51,
When the accelerator switch 52, the clutch switch 57, and the antilock switch 53 are all closed, the lamp 66 such as a pilot lamp or a brake lamp is turned on, and the exhaust brake 54 (or the hydraulic retarder 11) is operating. To inform.

The three input terminals of the second AND circuit 68 receive a signal indicating that the retarder switch 5 is located at the three positions via the circuit 79 and the output signal of the first AND circuit 60 is applied to the circuit 8.
0 and the detection signal from the third liquid temperature detection means 44 is inverted and connected via a circuit 81 having a knot circuit 69. The output terminal of the second AND circuit 68 is connected to the switch 45 via the circuit 85, and the switch 45 is closed by an output signal from the second AND circuit 68.
By the closing operation of the switch 45, the operation of the second switching valve 32 by the retarder switch 5 is ensured, and by the opening operation, the second switching valve 32 takes the position c regardless of the switching position of the retarder switch 5. As a result, the air chamber 25 d of the air-liquid converter 25 is supplied with the relatively low-pressure air from only one of the pressure reducing valves 33.
The generation of the detection signal by the third liquid temperature detecting means 44 turns on the warning lamp 70 such as a yellow lamp.

Further, the electric motor 22a and the fan 23a are driven via the circuit 82 by the detection signal from the fourth liquid temperature detecting means 46, and the closed circuit 21 is
While circulating the working liquid such as the fluid type retarder 11,
The working liquid cooler 23 is operated.

Next, the operation of the above embodiment will be described. First, when the exhaust brake switch 51 is closed while the vehicle is running, the accelerator switch 52 is closed without the accelerator pedal being depressed, the clutch switch 57 is closed without the clutch pedal being depressed, and the anti-lock brake system is activated. When the antilock switch 53 is closed in a non-operating state, the exhaust brake 54 starts operating. In the following description, the vehicle is in a normal deceleration running state by the exhaust brake 54, the exhaust brake switch 51, the accelerator switch 52, the clutch switch 57, and the anti-lock switch 53 are all closed and the pressure switch 55 is in the operating state. Assume that it is in the opening operation state.

Next, when the retarder switch 5 is switched to, for example, two positions, the compressed air from the compressed air source 4 is introduced into the pressure chamber 17c of the pneumatic cylinder device 17 via the first switching valve 31, and the clutch device 13 is connected.
That is, the first switching valve 31 is switched to switch the pressure chamber 17
When the pressurized air from the pressurized air source 4 is introduced into the connection member 17b through the diaphragm 17a, the clutch plate 18 that rotates integrally with the rotary shaft 10 is pressed.
Then, the pressure plate 14 supported by the second bearing 13b is pressed, and the clutch device 13 is connected.

As a result, the first bearing 13 is attached to the case 11c.
The support member 19, which is rotatably supported via the like, rotates, so that the rotor 16 integrated with the support member 19 starts rotating integrally with the rotating shaft 10. At this time, the second switching valve 32 takes the position c, and the pressure air of the pressurized air source 4 is reduced in pressure by one of the pressure reducing valves 33 to a comparatively low set pressure, and is sent to the air chamber 25 d of the air-liquid conversion device 25. A relatively small braking torque corresponding to the supplied and relatively low set pressure is generated in the hydraulic retarder 11. That is, the kinetic energy is given by the stirring of the rotor 16 in a circulating state in which the working liquid also serving as cooling flows in from the working liquid inlet 11a and flows out from the working liquid outlet 11b by the self-pumping action of the rotor 16. Working liquid collides with the stator 15,
A braking action is obtained while being transmitted to the working liquid as heat. At this time, the clutch device 13 is also cooled by the working liquid.

Next, when the retarder switch 5 is switched to the 3 position, the second switching valve 32 is switched to the d position while the clutch device 13 remains connected, and the pressure air of the pressure air source 4 is supplied to the other pressure reducing valve. The pressure in the air chamber 25 of the air-liquid conversion device 25 is adjusted to a relatively high set pressure by the pressure reducing device 34.
d, and a relatively large braking torque corresponding to a relatively high set pressure is generated in the hydraulic retarder 11.

During the operation of the fluid type retarder 11, the working liquid has a relatively low fourth predetermined temperature (for example, 80 ° C.).
° C) is detected by the fourth liquid temperature detecting means 46, the pump 22 is driven to rotate by the electric motor 22a, and the working liquid cooler 23 is
The air is cooled by 3a.

When the temperature of the working liquid rises and a third predetermined temperature (for example, 120 ° C.) in the middle of the working liquid is detected by the third liquid temperature detecting means 44, the detection signal is sent to the knot circuit 69. The signal is supplied to the second AND circuit 68 in an inverted manner, and the alarm lamp 70 is turned on. In addition, as long as the signals from the two circuits 79 and 80 are input to the second AND circuit 68, the switch 45 is provided with an opening operation, so that the switch 45 is switched to the third position even though the retarder switch 5 is switched to the third position. By causing the 2 switching valve 32 to assume the position c, the air chamber 25d of the air-liquid converter 25 is supplied with the relatively low-pressure air only from one of the pressure reducing valves 33.

If there is no detection signal from the third liquid temperature detecting means 44, the switch 45 is closed, so that the retarder switch 5 is switched to the third position and the second AND circuit 68 is connected to the circuit. When the signal from 80 is input, the second switching valve 32 can be switched to the d position. However, when the signal from the circuit 80 is not input to the second AND circuit 68, the switch 43 is opened and the first switching valve 31 is switched to the position a as described later, and the operation of the fluid type retarder 11 is performed. Is stopped.

Further, the temperature of the working liquid rises, and the first or second predetermined temperature (for example, about 130 to 150 ° C.) of the working liquid is changed to the first liquid temperature detecting means 41 or the second liquid temperature detecting means 42.
, The detection signal is input to the first AND circuit 60 via the OR circuit 64 and the knot circuit 62, and the buzzer 65 emits an alarm sound. Therefore, even when a signal indicating that the retarder switch 5 takes the 2 or 3 position is input to the other input terminal of the first AND circuit 60, the switch 43 is disconnected and the first switching valve 31 is turned off. Since the position is switched to the position a, the pressure chamber 17c of the pneumatic cylinder device 17 is drained, and the diaphragm 17a and the connecting member 17b are returned by a spring (not shown), so that the clutch device 13 is disconnected.

Although the retarder switch 5 takes two or three positions in this way, the hydraulic retarder 11
Of the fluid retarder 11 is prevented, so that troubles caused by overheating of the fluid type retarder 11, particularly fire, are prevented. In this way, the relatively high first or second predetermined temperature of the working liquid is applied to one of the first liquid temperature detecting means 41 and the second liquid temperature detecting means 42 while taking into account the temperature decrease accompanying the flow of the working liquid. Therefore, the first liquid temperature detecting means 41
Is provided on the outer peripheral half of the fluid-type retarder 11 so that the temperature of the working liquid in the fluid-type retarder 11 in the agitated state is relatively accurately detected by the rotor 16. The possibility of overheating of the type retarder 11 can be accurately detected.

Of course, if the retarder switch 5 is switched to the 1 position and turned off, the clutch device 13 is disconnected,
When the rotation of the rotor 16 is stopped, the second
The switching valve 32 returns to the position c.

[0039]

[Effect of the Invention] As understood from the above description,
According to the fluid type retarder control device of the present invention, the following effects can be obtained. (1) Since the temperature of the working liquid of the fluid type retarder device is detected at two points, that is, the fluid type retarder and the working liquid cooler, it is difficult to cause non-uniform heat distribution and malfunction due to foreign matter adhesion. Since the overheating of the fluid retarder is well prevented, the failure of the fluid retarder due to damage to the rubber seal is effectively prevented, and a fire is avoided, and the safety and reliability of the fluid retarder are reduced. The sex is improved together.

(2) Since the temperature of the working liquid of the fluid type retarder device is detected at two points, that is, the fluid type retarder and the working liquid cooler, and the temperature detected by the working liquid cooler is set lower, It is possible to accurately detect the abnormal temperature rise of the liquid and prevent the fluid retarder from overheating. Further, since the temperature of the working liquid in the fluid type retarder is detected in the outer peripheral half of the fluid type retarder, the abnormal temperature rise of the working liquid can be detected more accurately.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a hydraulic retarder device according to an embodiment of the present invention.

FIG. 2 is a circuit diagram showing a hydraulic retarder control device.

[Explanation of symbols]

1: fluid retarder unit, 2: cooler / pump unit, 3: pressure controller, 4: pressure air source, 5: retarder switch, 10: rotary shaft, 11: fluid retarder, 1
1a: working liquid inlet, 11b: working liquid outlet, 11c:
Case, 12: retarder chamber, 13: clutch device, 13
a: first bearing, 13b: second bearing, 14: pressure plate, 15: stator, 16: rotor, 17: pneumatic cylinder device (drive device), 17a: diaphragm, 1
7c: pressure chamber, 18: clutch plate, 19: support member, 21: closed circuit, 22: pump, 22a: electric motor, 23: cooler for working liquid, 25: air-liquid converter, 2
5a: air-liquid converter main body, 25b: rubber film, 25c: working liquid chamber, 25d: air chamber, 31: first switching valve,
32: second switching valve, 33, 34: pressure reducing valve, 4
1: first liquid temperature detecting means, 42: second liquid temperature detecting means, 4
3, 45: switch, 44: third liquid temperature detecting means, 46:
Fourth fluid temperature detecting means, 50: power supply, 51: exhaust brake switch, 52: accelerator switch, 53: antilock switch, 54: exhaust brake, 55: pressure switch,
57: clutch switch, 60: first AND circuit, 6
1, 62, 69: knot circuit, 64: OR circuit, 68:
Second AND circuit.

Claims (1)

(57) [Scope of request for utility model registration] Claims: 1. A rotating shaft that rotates with a wheel,
A hydraulic retarder that is always filled with a working liquid and includes a rotor and a non-rotating stator, a clutch device driven by a driving device to connect or disconnect the rotor and the rotating shaft, and the hydraulic retarder A closed circuit connecting the working liquid inlet and the working liquid outlet of the working liquid via a working liquid cooler, a pneumatic-liquid conversion device for applying air pressure to the working liquid in the closed circuit, and a pneumatic liquid from the pressurized air source. A pressure reducing valve capable of switching at least a high pressure and a low pressure of air supplied to the conversion device, and a first liquid temperature detection provided at an outer peripheral half of the fluid type retarder and detecting a first predetermined temperature of the working liquid. Means for detecting a second predetermined temperature of the working liquid which is provided in the working liquid cooler and which is lower than the temperature detected by the first liquid temperature detecting means in accordance with a temperature decrease accompanying the flow of the working liquid. Detection means And when one of the liquid temperature detecting means detects that the working liquid has risen to one of the predetermined temperatures, the driving device is driven to disconnect the clutch device. Hydraulic retarder control device.