JPH0565722U - Fluid type retarder - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a fluid type retarder device. [Structure] Provided on a rotary shaft 10 that rotates together with wheels,
A fluid type retarder 1 which is constantly filled with a working fluid, a working liquid inlet 11a and a working liquid outlet 11b of the fluid type retarder 1.
A closed circuit 21 that connects between and with a working liquid cooler 23, and a reservoir 25 that is connected to the closed circuit 21 and that can absorb an increase in internal pressure of the fluid retarder 1. Flexible film 25 that is easily deformable inside the main body 25a
It is divided into a working liquid chamber 25c and an air chamber 25d by b and 25g, and the working liquid chamber 25c is connected to the closed circuit 21. [Effect] Since the leakage of the working liquid and the mixing of air are prevented, the operation of the fluid retarder can be stably obtained. The peak torque value generated immediately after the start of the braking operation due to the expansion deformation of the flexible film is effectively reduced. Expansion and contraction deformation of the flexible film is facilitated, and a braking torque is stably obtained.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a fluid type retarder device.

[0002]

[Prior Art]

 It is known that large vehicles such as trucks and buses are equipped with a fluid retarder device. The fluid retarder device generates a braking torque when descending a slope or decelerating from a high speed to prevent fade due to temperature rise of the brake, improving vehicle safety and durability of friction material.

As a conventional fluid type retarder device, for example, there is one disclosed in JP-A-63-306956. This fluid retarder device is a fluid retarder that includes 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 non-rotatably fixed to the vehicle body. Therefore, the rotor is connected and fixed to the rotating shaft side, and the braking torque is generated by the kinetic energy of the working liquid between the stator and the rotor. The hydraulic retarder that houses the stator and rotor is constantly filled with working liquid.

It has been proposed that such a fluid type retarder should be provided with a closed circuit for connecting the working liquid inlet and the working liquid outlet of the fluid type retarder via a cooler for working liquid. There is.

Further, it has been proposed to add an air-liquid converter to the closed circuit and adjust the pressure of the working fluid in the closed circuit with pressurized air in order to adjust the braking torque by the fluid retarder. There is. In this type of air-liquid converter, the working liquid and pressure air are introduced through a baffle plate or filter into the air-liquid conversion chamber that also serves as the inner working liquid chamber and air chamber, and the working liquid and pressure A structure that directly contacts the air or a structure that separates the working liquid chamber and the air chamber in the conversion chamber by a piston is used.

[0006]

[Problems to be solved by the device]

 However, in such a conventional liquid-filled fluid type retarder device, when the air-liquid converter having the above structure is provided, an air-liquid converter having a structure in which the working liquid and the pressurized air are in direct contact with each other. In that case, there is a fatal technical problem that the working liquid and the pressurized air are insufficiently separated, the working liquid leaks out little by little, and the function of the liquid type fluid type retarder is gradually deteriorated. In an air-liquid converter with a structure in which the working liquid chamber and the air chamber are partitioned by a piston, the responsiveness between the pressure of the pressurized air and the pressure of the working liquid is poor, so a prescribed braking torque can be quickly applied. There is a technical problem that cannot be obtained.

In addition, when an air-liquid converter having a structure in which the working liquid chamber and the air chamber are partitioned by a piston is provided, the responsiveness between the pressure of the pressurized air and the pressure of the working liquid is poor, and in particular, the fluid type The relatively sharp reduction in peak torque value that occurs immediately after the retarder starts operating occurs slowly with the movement of the piston, which causes a large connection shock in the clutch device and gives an unpleasant braking feeling to the occupant. In addition, since the friction material of the clutch device is worn away, the durability is poor and a large-sized clutch device is required.

[0008]

[Means for Solving the Problems]

 The present invention has been made in view of the above-mentioned conventional technical problems, and the structure thereof is a fluid type retarder which is provided on a rotating shaft that rotates together with a wheel and which is constantly filled with a working liquid, and the fluid type retarder. A closed circuit that connects the working liquid inlet and the working liquid outlet of the hydraulic retarder with a cooler for the working liquid interposed, and a reservoir that is connected to the closed circuit and can absorb an increase in the internal pressure of the fluid retarder. A fluid characterized in that the reservoir is divided into a working liquid chamber and an air chamber by a flexible membrane that is easily deformable inside the reservoir body, and the working liquid chamber is connected to the closed circuit. It is a retarder device. Then, the air chamber of the reservoir can be connected to a pressurized air source capable of supplying pressurized air of a predetermined pressure.

[Action]

If the fluid type fluid retarder device is operated while the vehicle is traveling, the braking torque value rapidly increases due to the agitation of the filled working liquid at the beginning of the operation, and the maximum peak value is reached. Reach torque value. This peak torque value occurs in proportion to the pressure of the hydraulic fluid. Then, after reaching the peak torque value, it converges to a substantially flat and steady set torque value.

[0010] Accordingly, according to this fluid type retarder device, the pressure increase of the working liquid in the fluid type retarder toward the generation of the peak torque value is absorbed by the reservoir. That is, as the internal pressure of the fluid retarder rises, the working liquid in the fluid retarder flows into the working liquid chamber, and the flexible membrane expands and deforms toward the air chamber. As a result, the rise in internal pressure of the fluid type retarder is suppressed, and the peak torque value generated immediately after the start of operation is significantly reduced.

In the circulation state in which the function of the retarder device is exerted as described above and the working liquid that also serves as a cooling due to the self-pumping action or the like flows in from the working liquid inlet and flows out from the working liquid outlet, Is absorbed and transferred as heat to the hydraulic fluid to obtain control. The working liquid flowing out from the working liquid outlet is cooled and circulated in the working liquid cooler.

When the operation of the fluid retarder is stopped, the pressure rise due to the agitation of the working liquid in the fluid retarder decreases, and the flexible membrane contracts and deforms. Since almost no force is consumed for such deformation of the flexible film, the expansion / contraction deformation does not cause hysteresis, and the air pressure in the air chamber and the working liquid pressure in the working liquid chamber are always equal. .. Since the flexible film has airtightness, it is surely prevented that the air in the air chamber mixes with the working liquid in the working liquid chamber or the working liquid in the working liquid chamber leaks to the outside.

Further, when the air chamber of the reservoir is connected to a pressure air source capable of supplying pressure air of a predetermined pressure, the flexible membrane is deformed by the pressure air from the pressure air source, and the same pressure is applied. Since the liquid is obtained in the working liquid chamber of the reservoir, the braking torque according to this pressure can be generated in the fluid type retarder.

[0014]

【Example】

 Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1 to 6 show an embodiment of the present invention. As shown in FIG. 1, the fluid type retarder device has a fluid type retarder 1, a cooler / pump unit 2, a pressure control device 3, a pressure air source 4 and a retarder switch 5 as main components. The fluid retarder 1 includes a non-rotating case 11 that is fixed to a vehicle body-side member such as a transmission rear cover (not shown), and has a center portion of the case 11 whose one end is connected to a transmission output shaft or the like. The shaft 10 is rotatably and liquid-tightly penetrated with an appropriate seal member and a bearing interposed. The other end of the rotating shaft 10 is connected to a wheel via a propeller shaft (not shown) and rotates together with the wheel.

In this way, the retarder chamber 12 which is partitioned by the case 11 and which is constantly filled with the working liquid (oil or water) is liquid-tightly defined around the rotary shaft 10. Inside the retarder chamber 12, a stator 15 having radial blades centering on the rotating shaft 10 is provided, and having radial blades centering on the rotating shaft 10 is opposed to the stator 15. Then, the rotor 16 which can be fixed so as not to be relatively rotatable is provided on the member on the side of the rotating shaft 10. The stator 15 is integrated with the case 11 and is fixed to the vehicle body-side member so as not to rotate substantially.

Further, the case 11 is provided with a working liquid inlet 11 a at the center of the retarder chamber 12, and a working liquid outlet 11 b at the outer periphery of the retarder chamber 12.

Further, a wet multi-plate clutch device 13 capable of connecting and disconnecting the member on the rotary shaft 10 side and the rotor 16 is arranged on the inner peripheral portion of the rotor 16. The clutch device 13 is fixed to a plurality of annular pressure plates 14 and a rotor 16 and is rotatably supported by the case 11 via a first bearing 13a so that the pressure plate 14 is spline-coupled. And a second supporting member 13b that rotatably supports the movable pressure plate 14 located at one end. 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, and a connecting member 17b connecting the diaphragm 17a and the second bearing 13b.

On the other hand, the plurality of clutch plates 18 are spline-coupled to the rotating shaft 10 so as to be movable in the axial direction, and are sandwiched between the pressure plates 14.

Therefore, 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 member 17b. The movable pressure plate 14 located at one end is pushed in via the bearing 13b, and the pressure plate 14 is pressed against the clutch plate 18 that rotates integrally with the rotating shaft 10, so that the clutch device 13 is connected. As a result, the cylindrical support member 19 rotatably supported by the case 11 via the first bearing 13a rotates, so that 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 has 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, and the position where the pressure air of the pressure air source 4 is supplied to the pressure chamber 17c and the pressure chamber 17c are drained. And a position to do. Further, the second switching valve 32 is interposed between the pressure air source 4 and an air chamber 25d of a reservoir 25, which will be described later, via a pair of pressure reducing valves 33, 34 connected in parallel on the upstream side. 4 has a position to supply the pressure air of No. 4 to the air chamber 25d through one of the pressure reducing valves 33 or 34.

Since the paired pressure reducing valves 33, 34 are set to different set pressures, the pressure air of the pressure air source 4 is changed depending on the normal position of the second switching valve 32. The pressure is adjusted to a relatively low set pressure by the pressure reducing valve 33 and is supplied to the air chamber 25d of the reservoir 25, and the pressure air of the pressure air source 4 is changed by the switching operation of the second switching valve 32. The pressure is adjusted to a relatively high set pressure by 34 and is supplied to the air chamber 25d of the reservoir 25.

The first switching valve 31 and the second switching valve 32 are connected to the retarder switch 5 so that both valves 31 or 32 can be selectively switched. On the other hand, the working liquid inlet 11 a provided in the case 11 is connected to the working liquid outlet 11 b provided in the case 11 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 circulate the working liquid sequentially from the working liquid inlet 11a side. The pump 22 is rotationally driven by an electric motor 22a, and the hydraulic fluid cooler 23 is air-cooled by a fan 23a.

A reservoir 25 for absorbing an increase in the internal pressure of the fluid retarder 1 is provided with a pipe 28 at an appropriate position of the closed circuit 21 (in the illustrated embodiment, an upstream portion of the working liquid cooler 23). Connected through. As shown in FIGS. 2 and 3, the reservoir 25 includes a working liquid chamber 25c for storing working liquid and an air inside the reservoir body 25a by a rubber film 25b which is an airtight and easily deformable flexible film. It is configured to be divided into a chamber 25d. The working liquid chamber 25c is always connected to the closed circuit 21 through the through hole 25e, and the air chamber 25d is connected to the second switching valve 32 and the upstream side in parallel through the through hole 25f. It is connected to the pressure air source 4 through either of the pressure reducing valves 33 and 34 and is supplied with pressure air of a predetermined pressure. The rubber film 25b is given a wavy shape in the free state shown in FIGS. 2 and 3 to facilitate expansion / contraction deformation.

A working liquid reservoir 27 is connected to the working liquid chamber 25 c via a manual switching valve 26, and the working liquid in the working liquid reservoir 27 is stored in the reservoir 25 by the switching operation of the manual switching valve 26. It can be supplied to the working liquid chamber 25c.

Next, the operation of the above embodiment will be described. While the vehicle is running, the retarder switch 5 is turned on, the pressure air from the pressure air source 4 is introduced into the pressure chamber 17c of the pneumatic cylinder device 17 through the first switching valve 31, and the clutch device 13 is engaged. Let That is, when the first switching valve 31 is switched to introduce the pressure air from the pressure air source 4 into the pressure chamber 17c, the connecting member 17b is pushed in via the diaphragm 17a, so that the rotation is performed via the second bearing 13b. The pressure plate 14 is pressed against the clutch plate 18 that rotates integrally with the shaft 10, and the clutch device 13 is connected. As a result, the support member 19 rotatably supported by the case 11 via the first bearing 13 and the like rotates, so that the rotor 16 integral with the support member 19 starts integral rotation with the rotary shaft 10.

At the beginning of the operation of such a fluid-filled fluid type retarder device, as shown in FIG. 6, the agitation of the working fluid filled by the rotor 6 causes the braking torque value to rapidly increase and reach the maximum value. The peak torque value a is reached. This peak torque value a occurs in proportion to the pressure of the working liquid. After reaching the peak torque value a, it converges to a substantially flat and steady set torque value (c).

Therefore, according to this fluid retarder device, the increase in the pressure of the working liquid in the fluid retarder 1 toward the generation of the peak torque value a is absorbed by the reservoir 25. That is, as the internal pressure of the fluid type retarder 1 rises, the working liquid in the fluid type retarder 1 flows into the working liquid chamber 25c. The inflow of the working liquid elastically expands and deforms the rubber film 25b as shown in FIG. 5, and the air is compressed by the pressure reducing valve 33 (or 34) in the air chamber 25d. As a result, the rise in the internal pressure of the fluid retarder 1 is suppressed, and the peak torque value a generated immediately after the start of operation is significantly reduced as compared with the conventional product b indicated by the broken line. As a result, a large connection shock is generated in the clutch device 13 and an unpleasant braking feeling is prevented from being given to an occupant, and wear of the friction material is suppressed by the small-sized clutch device 13 to improve durability. improves.

In this way, the function of the retarder device is exerted. That is, by the self-pumping action of the rotor 16 and the pump 22, the working liquid also serving as cooling flows in from the working liquid inlet 11a and flows out from the working liquid outlet 11b, so that the rotor 16 is stirred. Then, the working liquid to which the kinetic energy is applied collides with the stator 15 and is transmitted to the working liquid as heat to obtain a braking action. At that time, the clutch device 13 is also cooled by the working liquid. The working liquid flowing out from the working liquid outlet 11b is cooled and circulated in the working liquid cooler 23 which is air-cooled by the fan 23a.

Further, the retarder switch 5 is operated to switch the second switching valve 32, and the pressure air of the pressure air source 4 is decompressed and adjusted by the other decompression valve 34 to a relatively high set pressure, and the reservoir 25 If the rubber film 25b is supplied to the air chamber 25d, the expanded rubber film 25b contracts and deforms, and the pressure of the working liquid stored in the working liquid chamber 25c rises, and the hydraulic retarder 1 responds to this rise in pressure. Generated braking torque.

When the retarder switch 5 is turned off, the clutch device 13 is disengaged, the rotation of the rotor 16 is stopped, and the pressure increase due to the agitation of the working liquid in the fluid retarder 1 is reduced. Air corresponding to a relatively low set pressure by the one pressure reducing valve 33 flows into the air chamber 25d, and the rubber film 25b contracts and deforms as shown in FIG. Since such deformation of the rubber 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 pressure in the working fluid chamber 25c are always equal to each other. Becomes Since the rubber film 25b has airtightness, it is reliably prevented that the air in the air chamber 25d mixes with the working liquid in the working liquid chamber 25c or the working liquid in the working liquid chamber 25c leaks to the outside. It

7 to 9 show other structural examples of the reservoir 25, and since the parts other than the shape of the easily deformable rubber film 25g are substantially the same as the reservoir 25, the same reference numerals are given. And their description is omitted. In the free state, the rubber film 25g has a mountain shape in which the lower center is bent upward toward the inside of the rubber film 25g as shown in FIG.

The peak torque value a generated immediately after the start of the operation of the fluid retarder 1 is such that the working liquid in the fluid retarder 1 flows into the working liquid chamber 25c as the internal pressure of the fluid retarder 1 rises. The membrane 25g expands and deforms as shown in FIG. 9, and the air in the air chamber 25d is compressed and alleviated. Further, when the retarder switch 5 is turned off, the pressure increase due to the agitation of the working liquid in the fluid retarder 1 decreases, so that a relatively low set pressure by the pressure reducing valve 33 in the air chamber 25d of the reservoir 25 is set. Corresponding air flows in, and the rubber film 25g contracts and deforms as shown in FIG. Therefore, also with this structural example, it is possible to obtain an operation substantially similar to that of the above-described embodiment.

[0033]

[Effect of the device]

 As can be understood from the above description, the following effects can be obtained by the fluid type retarder device according to the present invention. (1) Since the leakage of the working liquid and the mixing of air into the working liquid are prevented, the operation of the fluid type retarder can be stably obtained and its reliability is improved.

(2) The peak torque value generated immediately after the start of the braking operation due to the expansion deformation of the flexible film is effectively reduced. As a result, the connection shock is reduced, the braking feeling is improved, the wear of the friction material of the clutch device of the fluid retarder is reduced, and the durability is improved by adopting a small clutch device. .. (3) Expansion and contraction deformation of the flexible membrane is facilitated, and the air pressure on both sides of the flexible membrane and the working liquid pressure are well equalized, so a stable braking torque is obtained and the reliability of the fluid retarder device is improved. The property is improved.

[Brief description of drawings]

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

FIG. 2 is a sectional view showing a reservoir of the same.

3 is a sectional view taken along line III-III of FIG.

FIG. 4 is an explanatory view of the action of the reservoir.

FIG. 5 is an explanatory view of the action of the reservoir.

FIG. 6 is a diagram similarly showing generated torque-time characteristics.

FIG. 7 is a cross-sectional view showing a reservoir according to another structural example.

FIG. 8 is an explanatory view of the action of the reservoir.

FIG. 9 is an explanatory view of the action of the reservoir.

[Explanation of symbols]

1: Fluid type retarder, 2: Cooler / pump unit,
3: pressure control device, 4: pressure air source, 5: retarder switch, 10: rotating shaft, 11: case, 11a: working liquid inlet, 11b: working liquid outlet, 12: retarder chamber, 1
3: clutch device, 13a: first bearing, 13b: second bearing, 14: pressure plate, 15: stator, 1
6: rotor, 17: pneumatic cylinder device, 17a: diaphragm, 17c: pressure chamber, 18: clutch plate,
19: support member, 21: closed circuit, 22: pump, 22
a: electric motor, 23: cooler for working liquid, 25: reservoir, 25a: reservoir body, 25b, 25g: rubber film (flexible film), 25c: working liquid chamber, 25d: air chamber, 2
5e, 25f: through holes, 31: first switching valve, 32:
Second switching valve, 33, 34: pressure reducing valve.

Claims (2)

[Scope of utility model registration request] 1. A rotary shaft that rotates together with a wheel,
A fluid type retarder filled with a working fluid at all times, a closed circuit for connecting a working liquid inlet and a working liquid outlet of the fluid type retarder through a working liquid cooler, and a closed circuit connected to the closed circuit, A reservoir capable of absorbing an increase in internal pressure of the fluid type retarder, the reservoir being partitioned into a working liquid chamber and an air chamber by a flexible membrane that is easily deformable in the reservoir body, and the working liquid chamber is A fluid type retarder device, which is connected to a closed circuit. 2. The fluid type retarder device according to claim 1, wherein the air chamber of the reservoir of claim 1 is connected to a pressure air source capable of supplying pressure air of a predetermined pressure.