JP2547006Y2 - 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. BACKGROUND ART A fluid type retarder device is a fluid type retarder including 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 a vehicle body so as not to rotate, the rotor being rotated by a clutch device. Connected and fixed to the shaft side, a braking torque is generated by the kinetic energy of the working liquid between the stator and the rotor. The working liquid is filled in the fluid type retarder that houses the stator and the rotor.

[0003] In the conventional hydraulic retarder control device, the clutch device is disconnected by the drive device to give the inoperative state of the hydraulic retarder (1) position (OFF position), the clutch device is connected, One having a retarder switch sequentially having a position (2) for providing a low pressure state of the pressure reducing valve (low pressure position), and a position (3) for providing a high pressure state of the pressure reducing valve with the clutch device connected (high pressure position). Are known.

However, in this type of hydraulic retarder control device, when the retarder switch is instantaneously switched from the (1) position to the (3) position via the (2) position, an excessive load is applied to the clutch device. Therefore, it is necessary to use a large clutch device to ensure its durability, and a large peak torque value is generated in the hydraulic retarder in the early stage of the connection operation of the clutch device, thereby deteriorating the riding comfort of the vehicle. Let me. The peak torque value of the hydraulic retarder is
When a fluid-filled type hydraulic retarder is operated while a vehicle is running, the agitation of the filled working fluid causes an abrupt increase in the braking torque value at the beginning of the operation. Occurs in proportion to the pressure of
Then, after reaching the peak torque value, it converges to a substantially flat and steady set torque value.

[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 that applies air pressure to the working liquid in the closed circuit, a pressure reducing valve that can switch the pressure of air supplied from the pressure air source to the air-liquid converter to at least high pressure and low pressure, and When the clutch device is disconnected to provide an inoperative state of the hydraulic retarder, the clutch device is connected, the clutch device is connected, the pressure reducing valve is set to a low pressure position, and the clutch device is connected to the pressure reducing valve. A retarder switch having a high-pressure position for sequentially giving a high-pressure state, and when the retarder switch is switched to the high-pressure position, an on-delay timer for delaying a signal of the high-pressure position by a predetermined time during operation and outputting the signal is provided. It is a fluid type retarder control device characterized by the above-mentioned.

[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 fluid in the closed circuit, thereby responding to the control pressure. 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.

In operation of such a hydraulic retarder,
Since the signal of the high pressure position obtained by switching the retarder switch to the high pressure position is output from the on-delay timer with a delay of a predetermined time during operation, the braking torque state by the low pressure position is maintained during this time. As a result, even when the retarder switch is instantaneously switched from the OFF position to the high pressure position via the low pressure position, generation of high braking torque in the hydraulic retarder is prevented.

That is, the braking torque generated according to the control pressure of the working liquid of the hydraulic retarder generally rises rapidly at the beginning of braking when the retarder switch is switched from the OFF position to the low pressure position or the high pressure position, and has a peak. It decreases after reaching the torque value, and converges to a stable steady torque. Therefore, it is possible to reduce the peak torque value generated in the fluid type retarder by setting the above-mentioned predetermined time longer than the time required to generate a relatively low peak torque value corresponding to the relatively low control pressure. it can. This is because once the peak torque value is generated, even if the control pressure of the working liquid is increased, the braking torque value does not increase due to the rapid stirring of the working liquid.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. 1 to 5 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.

[0010] 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 cylindrical support member 19 rotatably supported via a, and spline-coupled to an appropriate pressure plate 14 so as to be slidably movable in the 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.

Thus, if the pressurized air from the pressurized air source 4 is supplied to the pressure chamber 17c of the pneumatic cylinder device 17 via the first switching valve 31, which will be described later, the diaphragm 17a, the connecting member 17b and the second bearing 13b 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 provided between the pressure air source 4 and the pressure chamber 17c of the pneumatic cylinder device 17 with a pressure reducing valve 35 interposed therebetween, and pressurizes the pressure air of the pressure air source 4 via the pressure reducing valve 35 into the pressure chamber 17c. And a position for draining the pressure chamber 17c. The second switching valve 32 includes a pair of pressure reducing valves 33 and 34 connected in parallel on the upstream side, and includes a pressure air source 4 and an air chamber 25d of the air-liquid converter 25 described later.
And a low-pressure position c and a high-pressure position d for supplying the pressurized air of the pressurized air source 4 to the air chamber 25d via one of the pressure reducing valves 33 or 34.

Since a set pressure having a different size is set in the pair of pressure reducing valves 33 and 34, the pressure air of the pressure air source 4 is reduced to one of the pressures 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 and 32 can be selected and switched and connected. On the other hand, the working liquid inlet 11 a provided in the case 11 c is connected to the closed circuit 21 and the cooler / pump unit 2.
Is connected to the working liquid outlet 11b provided in the case 11c through the opening. That is, the closed circuit 21 includes a pump 22 for circulating the working liquid sequentially from the working liquid inlet 11a side.
And the working liquid cooler 23 are connected. Pump 2
2 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 provided on the outer peripheral half of the fluid type retarder 11 and comprising 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 the time when the working liquid flows out from the second working liquid outlet 11b to the time when the working liquid flows through the closed circuit 21 and flows into the working liquid cooler 23 is considered. The first predetermined temperature (eg, 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 uses the one liquid temperature detecting means 41 or 42 to indicate that the working liquid has risen to one of the predetermined temperatures. Upon detection, the pneumatic cylinder device 17 is driven to return by draining, and the clutch device 1 is driven.
3 functions to cut. When the pneumatic cylinder device 17 is driven to return, the switch 43 is actually turned off, the first switching valve 31 is switched to the position a, and the diaphragm 17a and the connecting member 17b are driven by a spring (not shown).
It is done by restoring.

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, a fourth liquid temperature detecting means 46 for detecting a relatively low fourth predetermined temperature (for example, 80 ° C.) of the working liquid is provided. 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 (1) position, (2) position and (3) position. The (1) position is an OFF position in which the exhaust brake switch 51 is closed and only the exhaust brake 54 is operated, and the (2) position is that the second switching valve 32 is set to the low pressure position c and one of the pressure reducing valves 33 is operated. Is a low pressure position in which a relatively low pressure is applied to the air chamber 25d of the air-liquid conversion device 25 via the second switching valve 32 in the high pressure position d. Is a high pressure position for applying a relatively high pressure to the air chamber 25d of the air-liquid conversion device 25. In the positions (2) and (3), the clutch device 13 is connected to the pneumatic cylinder device 1.
7 is connected and driven.

A signal indicating that the retarder switch 5 is in the (2) position or the (3) position is supplied 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 detects a predetermined temperature is inverted via a circuit 78 including a knot circuit 62 and connected to each other. Therefore, the 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 the circuit 84, and the switch 43 is closed by an output signal from the first AND circuit 60. By closing the switch 43, the retarder switch 5 of the first switching valve 31
And the opening operation switches the retarder switch 5 to the position a regardless of the switching 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.

Further, the three input terminals of the second AND circuit 68 receive the signal of the retarder switch 5 at the position (3) via the circuit 79 and the output signal of the first AND circuit 60 via the circuit 80. Then, 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 circuit 8
5 and the second AND circuit 68
The switch 45 is given a closing operation by an output signal from the switch 45. By the closing operation of the switch 45, the operation of the second switching valve 32 by the retarder switch 5 is ensured,
Further, the opening operation causes the second switching valve 32 to assume the position c regardless of the switching position of the retarder switch 5 so that the air chamber 25d of the air-liquid conversion device 25 has a relatively low pressure only from one pressure reducing valve 33. Low pressure air is supplied.
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.

The circuit 79 includes an on-delay timer 59 (TDE) that delays during operation by a predetermined time t (for example, about 1 second). 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 pump 2
2, the working liquid such as the closed circuit 21, the hydraulic retarder 11, etc. is circulated, and 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, the retarder switch 5 is set to, for example, (2)
Switching to the position, the pressurized air from the pressurized air source 4
It 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, when the first switching valve 31 is switched to introduce the pressurized air from the pressurized air source 4 into the pressure chamber 17c, the connecting member 17b is pushed in through the diaphragm 17a, so that the clutch plate rotating integrally with the rotary shaft 10 is formed. The pressure plate 14 supported by the second bearing 13b is pressed against 18, 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 the same time, the clutch device 13 is cooled by the working liquid.

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

Since the on-delay timer 59 (TDE) is interposed in the circuit 79, the retarder switch 5
Is switched to the position (3) (high pressure position), the signal at the high pressure position is output from the on-delay timer 59 with a delay of a predetermined time t (1 second) as shown by a solid line in FIG. The signal is input to the AND circuit 68. During this time, the switch 45 is turned off and the second switching valve 32 takes the position c to substantially (2) despite the fact that the retarder switch 5 is switched to the position (3). The braking torque state of the position is maintained. A broken line shown in FIG. 3 indicates a second AND circuit 68 obtained when the on-delay timer 59 is not provided.
Is the input signal. As a result, even when the retarder switch 5 is instantaneously switched from the position (1) to the position (3) via the position (2), the generation of high torque within a predetermined time is prevented.

The fluid type retarder 1 thus obtained
The control pressure of the first working liquid will be described with reference to FIG. If the retarder switch 5 is set to the (1) position (or the (2) position), the second switching valve 32 takes the c position,
The pressure of the pressurized air from the pressurized air source 4 is reduced by a pressure reducing valve 33 to a relatively low set pressure, and the air-liquid conversion device 2
5 is supplied to the air chamber 25d, the control pressure of the working liquid of the hydraulic retarder 11 becomes relatively low (1 kgf / cm ² ) correspondingly, but the retarder switch 5 is set to (3). The predetermined time t (1
Second), the second switching valve 32 maintains the c position, so that the control pressure is also relatively low (1 kgf / cm ² ) during this time.
After a lapse of a predetermined time t (1 second), the second switching valve 32
Is switched to the d position, and is switched to a relatively high control pressure ( ² kgf / cm ² ) as shown by the solid line.

The braking torque (Kgf · m) generated by the hydraulic retarder 11 according to the control pressure of the working liquid of the hydraulic retarder 11 is determined by setting the retarder switch 5 to the (1) position as shown by the solid line in FIG. Instantaneously switches to the (3) position and rises at the same time as the peak torque value (about 70 kgf
m) and reaches a minimum value (approximately 40 kgf · m) corresponding to the relatively low control pressure (1 kgf / cm ² ) within a predetermined time t (1 second), that is, the retarder switch 5. Converges toward a steady torque value obtained by switching to the position (2), but after a lapse of a predetermined time t (1 second), the second switching valve 32 is switched to the position d. ) The torque rises to a steady torque value (about 50 kgf · m) obtained by switching to the position and stabilizes. FIG.
The dashed line shown in (3) indicates that the retarder switch 5 is instantly moved from the position (1) to the position (3) without the on-delay timer 59.
Shows the braking torque characteristics obtained when switching to the position,
(2) Since the clutch device 13 is connected at the same time as the switching to the position and the working liquid is rapidly stirred, and the control pressure of the working liquid is instantaneously switched to a relatively high control pressure ( ² kgf / cm ² ). It is known that high peak torque values (about 100 kgf · m) occur.

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 this state, the second
As long as the signals from the two circuits 79 and 80 are input to the AND circuit 68, the switch 45 is opened, so that the second switching valve is provided even though the retarder switch 5 is switched to the position (3). Let 32 take the c position,
One pressure reducing valve 3 is provided in the air chamber 25d of the air-liquid converter 25.
Only relatively low pressure air from 3 is supplied.

When 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 position (3) and the second AND circuit 68 When the signal from the circuit 80 is input to the second switching valve 32, the switching of the second switching valve 32 to the position d is possible. 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 if a signal that the retarder switch 5 takes the position (2) or (3) is input to the other input terminal of the first AND circuit 60, the switch 43 is disconnected and the first switch is cut off. Since the switching valve 31 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), and the clutch device 13 is returned.
Is disconnected.

In this way, the operation of the hydraulic retarder 11 stops even though the retarder switch 5 takes the position (2) or (3), so that the hydraulic retarder 1
The problem caused by the overheating of No. 1, especially fire, is 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, and the temperature of the working liquid in the fluid type retarder 11 in the agitated state by the rotor 16 is provided. In addition to the relatively accurate detection, the possibility of overheating of the fluid 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 disengaged, the rotation of the rotor 16 is stopped, and the second switching valve 32, which takes the d position, moves to the c position. Return.

In the above embodiment, when the retarder switch 5 is switched to the high-pressure position (3), an on-delay timer 59 is provided which delays the signal during operation and outputs it with a predetermined time t. Therefore, regardless of the time when the retarder switch 5 takes the position (2), (2)
The position state is extended for a predetermined time t. However, when the retarder switch 5 takes the (2) position,
After stabilizing to the steady torque value (about 40 kgf · m) shown in FIG. 5, a predetermined peak torque value (about 70 kgf
· After the occurrence of (m), even if the retarder switch 5 is subsequently switched to the position (3), an excessive peak torque value (approximately 100 kgf · m) due to rapid stirring of the working liquid may not occur. Absent. Thus, the above-mentioned predetermined delay time t depends on the time when the retarder switch 5 takes the position (2).
Can also be reduced.

[0044]

[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) When the retarder switch is switched to the high pressure position,
Since the signal at the high pressure position is output with a delay for a predetermined time during operation, the fluid type retarder prevents a sudden connection operation of the clutch device in a high pressure state, and wear of the friction material is reduced, so the clutch device is downsized. And improvement of durability can be satisfactorily compatible.

(2) Since the peak torque value of the braking torque generated in the fluid type retarder is effectively reduced, the braking feeling of the vehicle equipped with the fluid type retarder is improved by a simple structure to improve the riding comfort. can do.

[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.

FIG. 3 is a diagram showing switching positions of a time-retarder switch and input characteristics of a second AND circuit.

FIG. 4 is a diagram showing time-fluid retarder control pressure characteristics.

FIG. 5 is a graph showing time-braking torque characteristics.

[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, 59: on-delay timer,
60: first AND circuit, 61, 62, 69: knot circuit, 64: OR circuit, 68: second AND circuit, t: predetermined time.

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 the pressure of the air supplied to the converter to at least a high pressure and a low pressure, an OFF position for disconnecting the clutch device by the driving device to give an inoperative state of the hydraulic retarder, and connecting the clutch device. And a low pressure position for sequentially providing a low pressure position for providing a low pressure state of the pressure reducing valve, and a high pressure position for providing a high pressure state for the pressure reducing valve with the clutch device connected. And a switch, when the retarder switch is switched to the high-pressure position, hydraulic retarder control system and providing a on-delay timer for outputting delayed by a predetermined time during the operation of the signal of the high-pressure position.