JPH08230653A - Stream type retarder - Google Patents

Abstract

PURPOSE: To provide a steam type retarder capable of decreasing its receiving space by attempting the size reduction of an air-liquid converter as well as improving its reliability by stably obtaining its operation as the result of prevention of blockage of an operation liquid port by means of a flexible film. CONSTITUTION: An air-liquid converter 25 connected to an operational liquid flow passage 21 which provides connection between the operational liquid entrance 11a and the exit 11b of a steam type retarder 11 and makes increase/ decrease adjustment of the internal pressure of the stream type retarder 11 is subjected to partitioning of the inside of its air-liquid converter main body 25a inn an upper side operational liquid chamber 25c and a lower side air chamber 25d by means of an easily deformable flexible film 25b and a projection part 25f capable partitioning an operational liquid passage for providing communication between the operational liquid chamber 25c and an operational liquid port 25g is interposed between the flexible film 25b and the air-liquid converter main body 25a and around the operational liquid port 25g connected to the operational liquid flow passage 21.

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art It is known that a large vehicle such as a truck or a bus is always equipped with a fluid type retarder device which is filled with a fluid. The fluid retarder device generates a braking torque when descending a slope or decelerating from a high speed to prevent a fade due to an increase in temperature of the brake, thereby improving vehicle safety and durability of a friction material.

A conventional fluid type retarder device is disclosed in, for example, Japanese Patent Laid-Open No. 4-185759. This fluid type retarder device includes a rotor that can be fixed to a rotating shaft that rotates together with a wheel so that the rotor cannot rotate relative to the rotor, a stator that is provided so as to face the rotor and that is substantially fixed to a member on the vehicle body side, the rotating shaft and the rotor. And a clutch device capable of connecting and disconnecting the clutch device, the clutch device being fixed to the rotor, supporting the pressure plate and the plurality of separators movably in the central axis direction of the rotating shaft and rotatably supporting the case side. And a clutch plate that is disposed between the pressure plate and the separator and is movably supported on the rotary shaft side member in the central axis direction. It is housed in a case that is filled and fixed to the vehicle body side member.

In such a fluid type retarder device, the rotor is connected and fixed to the rotary shaft side by the clutch device, and the braking torque is generated by the velocity energy of the working liquid between the stator and the rotor. The case containing the stator and the rotor is constantly filled with the working liquid.
If the fluid-filled fluid-type retarder device is operated while the vehicle is running, the braking torque value rapidly increases due to the agitation of the filled working liquid at the beginning of the operation,
Reach maximum peak torque value. This peak torque value occurs in proportion to the pressure of the hydraulic fluid. After reaching the peak torque value, it converges to a substantially flat steady set torque value.

However, in the conventional fluid type retarder device, the working liquid flow path for connecting the working liquid inlet and the working liquid outlet of the fluid type retarder through the working liquid cooler and the working liquid flow path are provided. An air-liquid conversion device, which is connected to the flow path and can absorb an increase in the internal pressure of the fluid retarder, is provided.
In the air-liquid conversion device, the inside of the air-liquid conversion device is partitioned into a working liquid chamber and an air chamber by a flexible film that is easily deformable, and the working liquid chamber is connected to the working liquid flow path. This increases or decreases the pressure of the working liquid in the fluid retarder, adjusts the generated braking torque, and increases the pressure of the working liquid in the fluid retarder toward the peak torque value is It is adapted to be absorbed by the converter.

However, in such a conventional fluid type retarder device, air is supplied to the lower air chamber of the air-liquid conversion device, and the working liquid in the upper working liquid chamber is discharged from the upper working liquid port. It is a push-out structure, in which the flexible film is deformed upward. Therefore, in order to prevent the working liquid port from being blocked by the flexible film, a large volume of the working liquid chamber is ensured and the vertical deformation of the flexible film is allowed. as a result,
The air-liquid conversion device has become large in size and the storage space has been increased.

[0007]

The present invention has been made in view of the above conventional technical problems, and the structure thereof is as follows. According to the invention of claim 1, a fluid type retarder 11 which is provided on a rotating shaft 10 which rotates together with a wheel and which is constantly filled with a working liquid, and a working liquid inlet 11a and a working liquid outlet 11b of the fluid type retarder 11 are provided. A working liquid flow path 21 to be connected, and a connection to the working liquid flow path 21,
An air-liquid conversion device 25 for adjusting the internal pressure of the fluid-type retarder 11 to increase or decrease, and the air-liquid conversion device 25 uses an easily deformable flexible film 25b in the air-liquid conversion device body 25a to provide an upper working liquid chamber. 25c and the lower air chamber 25d,
The working liquid chamber 25c is connected to the working liquid flow path 21 through the working liquid port 25g of the air-liquid conversion device main body 25a, and operates between the flexible membrane 25b and the air-liquid conversion device main body 25a. A fluid type retarder device is characterized in that, around the liquid port 25g, a convex portion 25f capable of partitioning a working liquid flow path communicating the working liquid chamber 25c and the working liquid port 25g is interposed. The invention according to claim 2 is the fluid type retarder device according to claim 1, characterized in that the convex portion 25f has a rib shape and is formed in a plurality in a radial shape. The invention of claim 3 is the fluid type retarder device of claim 1 or 2, wherein the width of the convex portion 25f is formed smaller than the diameter of the working liquid port 25g.

[Action]

According to the invention of claim 1, the air-liquid conversion device 2
When pressurized air is supplied to the air chamber 25d on the lower side of 5, the flexible film 25b is stretched and deformed, and the working liquid of the same pressure generated in the working liquid chamber 25c flows through the working liquid port 25g of the air-liquid converter 25. It acts on the working liquid flow path 21 and thus on the fluid retarder 11, and a braking torque corresponding to the pressure is generated by the fluid retarder 11. And the air chamber 25
When pressurized air is supplied to d, the upper end of the flexible film 25b bulges like a balloon and tends to close the working liquid port 25g of the air-liquid conversion device 25.

However, the convex portion 25f is interposed between the inner surface of the air-liquid conversion device main body 25a and the flexible film 25b, and the working liquid flow path is formed between the convex portions 25f. This allows
The flow of the working liquid between the working liquid chamber 25c and the working liquid port 25g is ensured, and the normal function of the retarder device is ensured. If the pressure inside the air chamber 25d is reduced by stopping the operation of the retarder device, the working liquid port 25g
Since the pressure of the working liquid flowing back into the working liquid chamber 25c acts on the flexible film 25b, the flexible film 25b contracts and deforms, and the pressure air in the air chamber 25d flows out to the outside. Since such deformation of the flexible film 25b consumes almost no force, the expansion / contraction deformation does not cause hysteresis,
The air pressure in the air chamber 25d and the working liquid pressure in the working liquid chamber 25c are always substantially equal. In addition, the flexible film 25
Since b has airtightness, it is reliably prevented that the air in the air chamber 25d is mixed with the working liquid in the working liquid chamber 25c or the working liquid in the working liquid chamber 25c leaks to the outside.

According to the second aspect of the present invention, the plurality of convex portions 25f having a rib shape and radially formed define the working liquid flow passage that connects the working liquid chamber 25c and the working liquid port 25g. It Thereby, the working liquid chamber 25c
The flow of the working liquid between the inside and the working liquid port 25g is ensured, and the normal function of the retarder device is ensured.

According to the third aspect of the present invention, since the working liquid port 25g is not closed by the convex portion 25f, the working liquid flow passage that connects the working liquid chamber 25c and the working liquid port 25g is surely defined. . Thereby, the working liquid chamber 2
The flow of the working liquid between the inside of 5c and the working liquid port 25g is reliably ensured, and the normal function of the retarder device is ensured.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 4 show an 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.
A fluid type retarder unit 1, a cooler / pump unit 2, a pressure control device 3, a clutch control device 6, a pressure air source 4 and a retarder switch 5 are included as main components. The fluid type retarder 11 is provided with a non-rotating case 11c that is fixed to a body side member such as a frame side member (not shown) or a transmission rear cover.
A rotary shaft 10, one end of which is connected to a transmission output shaft or the like, rotatably and liquid-tightly penetrates through the center of c with an appropriate seal member and a bearing interposed. The other end of the rotary shaft 10 is connected to wheels via a propeller shaft (not shown) and rotates together with the wheels.

In this manner, the rotary shaft 10 is partitioned by the case 11c so as to always operate liquid (oil or water).
Liquid-tightly define the filled and filled retarder chamber 12. In the retarder chamber 12, a stator 15 having radial blades centered on the rotary shaft 10 is provided, and the stator 15 has radial blades centered on the rotary shaft 10.
A rotor 16 that is fixed to a member on the rotating shaft 10 side so as not to be rotatable relative to the stator 15 is provided. The stator 15 is integrated with the case 11c and is fixed to the vehicle body-side member in a substantially non-rotatable manner.

Further, the case 11c includes a retarder chamber 12
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, on the inner peripheral portion of the rotor 16, the rotary shaft 1
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 is
A plurality of annular separators 14b and the rotor 16
And a cylindrical separator case 19 which is fixed to the case 11c and is rotatably supported by the case 11c via the first bearing 13a, and supports an appropriate number of separators 14b by spline coupling so as to be slidably supported in the central axis direction. , A series of separators 1
Movable pressure plate 14 located at one end of 4b
A second bearing 13b that rotatably supports a is provided, and a fixed pressure plate 14c that is located at the other end of the series of separators 14b and that is fixed to the first bearing 13a.

A pneumatic cylinder device 17, which is a drive device, is attached to the clutch device 13. 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 with. 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 4a, 14c and the separator 14b.

However, if the pressure air from the pressure air source 4 is supplied to the pressure chamber 17c of the pneumatic cylinder device 17 via the first switching valve 31 described later, the diaphragm 17a, the connecting member 17b and the second bearing 13b. Since the movable pressure plate 14a located at one end is pushed in via the clutch plate 18 and the pressure plates 14a, 14c and the separator 14b are pressed against the clutch plate 18 rotating integrally with the rotating shaft 10, the clutch device 13 is connected. To do. As a result, the cylindrical separator case 19 rotatably supported by the case 11c via the first bearing 13a rotates, so that the rotor 16 integrated with the separator case 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 heat energy to generate a braking torque.

The clutch control device 6 has a first switching valve 31 and a pressure reducing valve 35. This first switching valve 3
1 is provided with a pressure reducing valve 35 between the pressure air source 4 and the pressure chamber 17c of the pneumatic cylinder device 17, and the pressure air of the pressure air source 4 is reduced through the pressure reducing valve 35 to reduce the pressure chamber 1
7b, and a position for draining the pressure chamber 17c.

The pressure control device 3 also has a second switching valve 32 and a third switching valve 95. The second switching valve 32 and the third switching valve 95 include a first pressure reducing valve 33, a second pressure reducing valve 34, and a low speed pressure reducing valve 93, which are pressure reducing means arranged in parallel on the upstream side, and are connected to the pressure air source 4. Switching for interposing with the air chamber 25d of the air-liquid conversion device 25, which will be described later, and supplying the pressure air of the pressure air source 4 to the air chamber 25d via any of the pressure reducing valves 33 or 34 or the low pressure reducing valve 93. It has a function as a valve. Therefore, the second switching valve 32 has the low pressure position d and the intermediate pressure / high pressure position c, and the third switching valve 95 has the intermediate pressure position e and the high pressure position f. The pipe 3 is provided between the second switching valve 32 and the air chamber 25d.
Connected by 6. And the second pressure reducing valve 3
4 and the low pressure reducing valve 93 are connected to one inlet port of the second switching valve 32 via the third switching valve 95.

Since the first and second pressure reducing valves 33, 34 and the low pressure reducing valve 93 are set to different set pressures, the pressure is changed by the low pressure position d in the normal state of the second switching valve 32. The pressure air of the air source 4 is decompressed and adjusted to a relatively low set pressure by the first decompression valve 33 and supplied to the air chamber 25d of the air-liquid conversion device 25. Also, the second
By making the switching valve 32 take the intermediate pressure / high pressure position c and making the third switching valve 95 take the intermediate pressure position e which is the normal state, the pressure air of the pressure air source 4 is made to flow by the second pressure reducing valve 34. The pressure is reduced to an intermediate pressure and introduced into the air chamber 25d of the air-liquid conversion device 25, and the second switching valve 32
By taking the intermediate pressure / high pressure position c and the third switching valve 95 at the high pressure position f, the pressure air of the pressurized air source 4 is depressurized to a high pressure by the low speed depressurizing valve 93, and the empty liquid is discharged. It is introduced into the air chamber 25d of the converter 25.

Therefore, the three pressure reducing valves 33 provided in the second switching valve 32 and the third switching valve 95,
34 and 93 function as pressure reducing valves capable of switching the pressure of the air supplied from the pressure air source 4 to the air chamber 25d of the air-liquid conversion device 25 to low pressure, intermediate pressure, and high pressure. The pressure reducing valves 33, 34 and the low pressure reducing valve 93
Can relieve the pressure on the secondary side, that is, on the air chamber 25d side of the air-liquid conversion device 25.

The first switching valve 31, the second switching valve 32, and the third switching valve 95 are connected to the retarder switch 5, and each valve 31, 32, or 95 is selected by a control circuit (not shown). Then, it can be switched and connected.

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, the closed circuit 21 is connected to the pump 22 and the working liquid cooler 23 that sequentially circulate the working liquid from the working liquid inlet 11a side. Pump 22
Is rotatably driven by an electric motor 22a, and the hydraulic fluid cooler 23 is air-cooled by a fan 23a.

Further, a pneumatic liquid for exerting air pressure on a suitable portion of the closed circuit 21 (one end portion of the working liquid cooler 23 in the illustrated embodiment) on the working fluid of the closed circuit 21 and by extension of the hydraulic 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 a pressure air source via either the second switching valve 32 or the third switching valve 95 described above and the three pressure reducing valves 33, 34, 93 arranged in parallel on the upstream side of both switching valves 32, 95. 4 air chamber 25d
Since the pressurized air having a predetermined pressure is supplied to the closed circuit 21, the pressure of the working liquid in the closed circuit 21 and further in the hydraulic retarder 11 can be adjusted to a high or low level. The working liquid chamber 25c also functions as a working liquid reservoir.

As shown in FIGS. 2 and 3, the flexible membrane 25b of the air-liquid conversion device 25 is fixed at the periphery of the opening at the lower end around the air port 25e of the air-liquid conversion device main body 25a to convert the air-liquid conversion device. A working liquid chamber 25c is defined between the apparatus body 25a and the flexible film 25b, and an air chamber 25d is provided inside the flexible film 25b.
Is partitioned. The working liquid chamber 25c communicates with the working liquid port 25g at the upper end of the air-liquid conversion device body 25a.

Then, near the upper end of the flexible film 25b,
The rib-shaped convex portions 25f are formed radially (three in the figure), and radial working liquid flow paths can be defined between the convex portions 25f. However, the width of each convex portion 25f is set to be smaller than the diameter of the working liquid port 25g of the air-liquid conversion device main body 25a, and the convex portion 25f allows the working liquid port 25g to be formed.
Is prevented from being blocked. In addition, each convex portion 25f
Is formed radially avoiding the central portion, and the upper end portion of the flexible membrane 25b, that is, the working liquid port 25 of the air-liquid conversion device main body 25a.
The convex portion 25f is prevented from being located at a position corresponding to g, and when the flexible film 25b is brought into close contact with the vicinity of the working liquid port 25g of the air-liquid conversion device main body 25a, the working liquid port 25g.
Is surely prevented from being blocked. The working liquid port 25g is always connected to the working liquid flow path 21, and the air port 25e is the both switching valve 3 described above.
2, 95 and a pressure reducing valve 33 connected in parallel to the upstream side,
It is connected to the pressurized air source 4 via one of 34 and 93, and pressurized air having a predetermined pressure is supplied.

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.

The first liquid temperature detecting means 41, which is provided in the outer half of the fluid type retarder 11 and includes a switch for detecting a relatively high first predetermined temperature (for example, 150 ° C.) of the working liquid, and the working liquid. The cooler 23 for a vehicle is provided with a temperature slightly higher 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 why the liquid temperature detecting means 41 is provided in the outer peripheral side half of the fluid type retarder 11 is that the inner peripheral side half of the fluid type retarder 11 in the agitated state due to the rotor 16 easily causes cavitation, and thus the working liquid in the agitated state. This is because it is difficult to accurately grasp the temperature of. 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 during the period of flowing out from the second working liquid outlet 11b, flowing through the closed circuit 21 and flowing into the working liquid cooler 23 is taken into consideration. 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 indicates that one of the liquid temperature detecting means 41 or 42 indicates that the working liquid has risen to any one of the predetermined temperatures. When it is detected, the pneumatic cylinder device 17 is drained so as to be driven to return, and the clutch device 13 is disengaged. In the return driving of the pneumatic cylinder device 17, the switch 43 is actually cut off to switch the first switching valve 31 to the a position, and the diaphragm 17a and the connecting member 17 are driven by a spring (not shown).
It is done by returning b.

Further, 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 is provided. 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, it causes the second switching valve 32 to take the low pressure position d and supplies the air to the air-liquid conversion device 25. Switch the pressure of to the low pressure side. Actually, the switch 45 is cut off, the second switching valve 32 is set to the low pressure position d, and the switching to the intermediate pressure / high pressure position c 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. Fourth liquid temperature detecting means 46
The detection signal from the electric motor 22a and the fan 2
3a is driven to circulate the working fluid such as the closed circuit 21, the fluid type retarder 11 and the like by the pump 22 and the cooler 23 for the working fluid is operated. A pressure switch 55 detects a pressure drop of the pressurized air source 4.

The retarder switch 5 has a (1) position,
It has switching positions of (2) position and (3) position.
The (1) position is the OFF position of the fluid retarder 11 that closes the exhaust brake switch to operate only the exhaust brake, and the (2) position causes the second switching valve 32 to take the low pressure position d to perform the first pressure reduction. At the low pressure position where a relatively low pressure is applied to the air chamber 25d of the air-liquid conversion device 25 via the valve 33, the (3) position allows the second switching valve 32 to take the intermediate pressure / high pressure position c, The air chamber 25d of the air-liquid conversion device 25 is supplied with intermediate or high pressure through the second pressure reducing valve 34 or the low pressure reducing valve 93 and the third switching valve 95.
This is the intermediate pressure / high pressure position applied to. Also, this (2)
In the position and the position (3), the clutch device 13 is connected and driven by the pneumatic cylinder device 17. Thus, the (2) position and the (3) position form the ON position of the fluid retarder 11.

Reference numeral 100 is a traveling speed detecting means, which is used when the vehicle exceeds a predetermined traveling speed.
00 is turned off, and the running speed detecting means 100 is turned on when the running speed of the vehicle is a predetermined running speed or less (for example, a vehicle speed of 50 km / h or less), and outputs a detection signal.

Next, the operation of the above embodiment will be described. When the retarder switch 5 is switched to, for example, the (2) position, the pressure air from the pressure 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 set to the b position so that the pressure chamber 17c
When the pressure air from the pressure air source 4 is introduced into the clutch plate 18, the connecting member 17b is pushed through the diaphragm 17a, so that the clutch plate 18 that rotates integrally with the rotating shaft 10
On the other hand, the movable pressure plate 14a 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.
Since the separator case 19 that is rotatably supported via the like rotates, the rotor 1 that is integral with the separator case 19
6 starts rotating integrally with the rotating shaft 10. At that time, the second switching valve 32 adopts the low pressure position d, the pressure air of the pressure air source 4 is decompressed and adjusted to a relatively low set pressure by the first decompression valve 33, and the air chamber 25d of the air-liquid conversion device 25 is reduced. And a relatively small braking torque corresponding to a relatively low set pressure is generated in the hydraulic retarder 11. That is,
Due to the self-pumping action 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, the operation in which the kinetic energy is applied by the stirring of the rotor 16 The liquid collides with the stator 15 and is transferred as heat to the working liquid to obtain a braking action. At the same time, the clutch device 13 is cooled by the working liquid.

Next, when the retarder switch 5 is switched to the (3) position, the switch 45 is closed by a signal from a control circuit (not shown), so that the second switching valve 32 is kept connected with the clutch device 13. Is switched to the intermediate pressure / high pressure position c. At that time, if the vehicle exceeds a predetermined traveling speed and the traveling speed detecting means 100 is OFF,
The pressure air from the pressure air source 4 is decompressed and adjusted to an intermediate set pressure by the second pressure reducing valve 34 and supplied to the air chamber 25d of the air-liquid conversion device 25, so that a slightly large braking torque according to the intermediate set pressure is generated. It is generated in the fluid retarder 11.

In this manner, when the vehicle decelerates or the traveling speed detecting means 100 is ON when the retarder switch 5 is switched to the (3) position, the detection signal of the traveling speed detecting means 100 is detected. Thus, the third switching valve 95 switches from the intermediate pressure position e to the high pressure position f. However, it is assumed that the third liquid temperature detecting means 44 has not detected that the working liquid has risen to the third predetermined temperature (for example, 120 ° C.).

When the third switching valve 95 is in the high pressure position f, the second switching valve 32 is in the intermediate pressure / high pressure position c, so that the high pressure air is converted into the air-liquid through the low pressure reducing valve 93. It is supplied to the air chamber 25d of the device 25.
As a result, while the vehicle is traveling at a predetermined traveling speed or less, the pressure air higher than the set pressure at the traveling speed exceeding the predetermined traveling speed is supplied to the air chamber 25d, and a larger braking is performed according to the high pressure air. Torque is generated in the fluid retarder 11. As a result, the shortage of the braking torque of the hydraulic retarder 11 at a predetermined traveling speed or less is compensated for, and an appropriate deceleration is obtained.

During operation of the fluid retarder 11, the working liquid has a relatively low fourth predetermined temperature (for example, 80).
° 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.

Further, if the temperature of the working liquid rises and the third predetermined temperature (for example, 120 ° C.) in the middle of the working liquid is detected by the third liquid temperature detecting means 44, it is not shown in the drawing based on the detection signal. Since the switch 45 is opened by the control circuit of No. 3, the low pressure position d is applied to the second switching valve 32 even though the retarder switch 5 is switched to the position (3).
As a result, relatively low pressure air is supplied only from the first pressure reducing valve 33 to the air chamber 25d of the air-liquid conversion device 25. Of course, even when the traveling speed detecting means 100 is ON, the second switching valve 32 takes the low pressure position d, so that high pressure air is supplied to the air chamber of the air-liquid conversion device 25 via the low pressure reducing valve 93. It is not supplied to 25d.

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 which is relatively high is the first liquid temperature detecting means 41 or the second liquid temperature detecting means 42.
If it is detected by either one of the above, the switch 43 is disconnected even if the detection signal is input to the retarder switch 5 in the (2) position or the (3) position. The first switching valve 31 is switched to the a position, 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),
The clutch device 13 is disengaged.

In this way, the operation of the fluid retarder 11 is stopped regardless of whether the retarder switch 5 is in the (2) position or the (3) position, so that the fluid retarder 1 is operated.
Problems caused by overheating of No. 1 are prevented. In this way, the relatively high first or second predetermined temperature of the working liquid is
The first liquid temperature detection means 41 or the second liquid temperature detection means 42 detects the temperature drop in consideration of the temperature drop accompanying the flow of the working liquid.
1 is provided in the outer peripheral side half of the fluid type retarder 11 so that the temperature of the working liquid in the fluid type retarder 11 in a stirring state can be detected relatively accurately by the rotor 16. The possibility of overheating of the expression retarder 11 can be accurately detected.

In this way, when the pressure air from the pressure air source 4 is supplied to the air chamber 25d of the air-liquid conversion device 25 with its height adjusted, the flexible film 25b is expanded or contracted to be deformed into the working liquid chamber 25c. The generated working liquid of the same pressure acts on the working liquid flow path 21 and further on the retarder chamber 12 of the fluid type retarder 11 via the working liquid port 25g at the upper end portion of the air-liquid conversion device 25 and the pipe 28, and responds to the pressure. Braking torque is generated by the fluid retarder 11. When pressurized air is supplied to the air chamber 25d, the upper end of the flexible film 25b bulges like a balloon as shown in FIG. 4, and closes the working liquid port 25g at the upper end of the air-liquid conversion device 25. Exhibit a tendency.

However, between the inner surface of the upper end of the air-liquid conversion device main body 25a and the flexible film 25b, the convex portions 25f formed in the flexible film 25b in the shape of a rib are radially interposed, and each convex portion is formed. Radial working liquid flow paths are formed between the portions 25f. This ensures the flow of the working liquid between the working liquid chamber 25c and the working liquid port 25g. As a result, the normal function of the retarder device is ensured. Also,
The width of the convex portion 25f is set to be smaller than the diameter of the working liquid port 25g of the air-liquid conversion device main body 25a to prevent the working liquid port 25g from being blocked by the convex portion 25f,
Further, the convex portions 25f are formed radially avoiding the central portion to prevent the convex portions 25f from being located at the upper end portion of the flexible film 25b, that is, at a position corresponding to the working liquid port 25g of the air-liquid conversion device main body 25a. , The flexible film 25b is the air-liquid conversion device main body 2
It is prevented that the working liquid port 25g is closed when it comes into close contact with the vicinity of the working liquid port 25g of 5a. As a result, the working liquid chamber 25c is constantly connected to the working liquid flow path 21, and the normal function of the retarder device is reliably ensured.

Of course, when 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 intermediate pressure / high pressure position c is used. Returns to the low pressure position d. As a result, the velocity energy of the working liquid does not act on the stator 15, and the operation of the retarder device stops.

When the pressure in the air chamber 25d is reduced by stopping the operation of the retarder device, the pressure of the working liquid flowing back from the working liquid port 25g into the working liquid chamber 25c is changed.
5b, the flexible film 25b contracts and deforms, and the pressure air in the air chamber 25d is relieved from the first pressure reducing valve 33. Since the deformation of the flexible film 25b consumes almost no force, the expansion / contraction deformation does not cause hysteresis, and the air pressure in the air chamber 25d and the working liquid chamber 2 are not changed.
The working liquid pressure within 5c is always substantially equal. Further, since the flexible film 25b has airtightness, the air chamber 25
The air in d mixes with the working liquid in the working liquid chamber 25c,
Alternatively, the working liquid in the working liquid chamber 25c is prevented from leaking to the outside.

In the above embodiment, when the traveling speed detecting means 100 receives a detection signal in the traveling state in which the second switching valve 32 is set to the intermediate pressure / high pressure position c, the third switching is performed. Although the valve 95 is switched to the high pressure position f, in the traveling state in which the second switching valve 32 is set to the low pressure position d, when the traveling speed detecting means 100 receives a detection signal, the second switching valve 32 is set to the intermediate state. The pressure and high pressure position c is set and the third switching valve 95
It is also possible to switch to the high pressure position f, switch from the operating position of the first pressure reducing valve 33 to the operating position of the low pressure reducing valve 93, and apply high pressure air to the air chamber 25d of the air-liquid conversion device 25.

5 to 7 show another structural example of the air-liquid conversion device 25, and the substantially same parts as those in the above-mentioned embodiment are designated by the same reference numerals. The air-liquid conversion device 25 is different from the above-described embodiment only in that the lower part of the air-liquid conversion device main body 25a is formed by a spherical surface portion 25h having an upward convex shape. With this air-liquid conversion device 25, the same operation as that of the air-liquid conversion device 25 of the above embodiment can be obtained.

By the way, in the above embodiment, the flexible film 2 is used.
A rib-shaped convex portion 25f was radially formed near the upper end portion of 5b, and a radial working liquid flow path was formed between the convex portions 25f. The working liquid flow path is secured between the flexible film 2 and the device body 25a.
It suffices to have a function of preventing the working liquid port 25g from being blocked by 5b. Then, even if the convex portions 25f are formed radially around the working liquid port 25g on the inner surface of the upper end portion of the air-liquid conversion device main body 25a, substantially the same action can be obtained.

[0050]

As can be understood from the above description,
According to the fluid retarder device of the present invention, the following effects can be obtained. According to the invention of claim 1, since the working liquid flow path is defined by the convex portion between the flexible film and the air-liquid conversion device main body, the working liquid port is blocked by the flexible film. This is prevented, and the working liquid chamber and the working liquid port are in constant communication. As a result, the operation of the fluid retarder can be stably obtained, the reliability is improved, and the space for the liquid can be reduced by downsizing the air-liquid conversion device.

[Brief description of drawings]

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

FIG. 2 is a sectional view showing an air-liquid conversion device of the same.

FIG. 3 is a plan view showing the air-liquid conversion device.

FIG. 4 is an explanatory view of the operation of the air-liquid conversion device.

FIG. 5 is a sectional view showing another structural example of the air-liquid conversion device.

FIG. 6 is a plan view showing another structural example of the air-liquid conversion device.

FIG. 7 is an operation explanatory view of another structure example of the air-liquid conversion device.

[Explanation of symbols]

1: Fluid type retarder unit, 2: Cooler / pump unit, 3: Pressure control device, 4: Pressure air source, 5: Retarder switch, 10: Rotating shaft, 11: Fluid type 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, 14a: movable pressure plate, 14b: separator, 14a: fixed pressure plate, 15: stator, 16: rotor,
18: Clutch plate, 19: Separator case, 2
1: working liquid flow path, 22: pump, 22a: electric motor, 23: cooler for working liquid, 25: air-liquid conversion device, 2
5a: Air-liquid conversion device main body, 25b: Flexible membrane, 25c: Working liquid chamber, 25d: Air chamber, 25f: Convex portion, 25g: Working liquid port, c: Intermediate pressure / high pressure position, d: Low pressure position,
e: intermediate pressure position, f: high pressure position.

Claims (3)

[Claims] 1. A fluid type retarder (1) which is provided on a rotating shaft (10) which rotates together with a wheel and which is always filled with a working liquid.
1) and the working liquid inlet (1) of the fluid retarder (11)
1a) and a working liquid flow path (21) connecting between the working liquid outlet (11b) and an empty space connected to the working liquid flow path (21) to increase or decrease the internal pressure of the fluid type retarder (11). A liquid conversion device (25), and the air-liquid conversion device (25)
Is partitioned into an upper working liquid chamber (25c) and a lower air chamber (25d) by an easily deformable flexible film (25b) inside the air-liquid conversion device body (25a). 25
c) is connected to the working liquid flow path (21) through the working liquid port (25g) of the air-liquid conversion device main body (25a), and the flexible membrane (25b) and the air-liquid conversion device main body (25).
a) between the working fluid port (25g) and the working fluid chamber (25c) and the working fluid port (25g).
Convex portion (25f) capable of partitioning the working liquid flow path communicating with
A fluid-type retarder device characterized by interposing a valve. 2. The fluid type retarder device according to claim 1, wherein the convex portion (25f) has a rib shape and is formed in a plurality in a radial shape. 3. The fluid type retarder device according to claim 1, wherein the width of the convex portion (25f) is smaller than the diameter of the working liquid port (25g).