JPH0777227A - Fluid type retarder - Google Patents

Abstract

PURPOSE: To provide a fluid type retarder having a reduced outer dimension and weight and facilitating adjustments of braking torque. CONSTITUTION: This fluid type retarder includes an adjustment means 12 for moving a fixed impeller 4 to an eccentric position, and at each position of the fixed impeller 4, balance is maintained between a braking reaction on the fixed impeller 4 and an opposite adjusting force exerted by the adjustment means 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fixed casing which can be filled with a working fluid, and a rotary impeller connected to a drive shaft.
The present invention relates to a fluid type retarder including a fixed impeller that can be moved so as to move away from a concentric position with respect to a rotary impeller.

[0002]

2. Description of the Related Art Retarders of this type are patented in West Germany.
No. 3,113,408. This retarder
It is used as an energy exchanger in a wind turbine for exchanging wind energy into heat via a heat exchanger.
In this case, it is necessary to adapt the characteristic of the retarder to the characteristic curve of the prime mover, eg a wind turbine.

This is done in known retarders by means of a device for moving the fixed impeller radially to a non-concentric position with respect to the rotary impeller. Therefore, the fixed impeller is eccentrically fixed on the shaft. Therefore, when the fixed impeller is rotated with respect to the rotary impeller, eccentricity occurs. When the shaft supporting the fixed impeller is rotated, the rotary impeller and the fixed impeller are aligned at a certain position. Furthermore, linear guides for fixed impellers are known, which guides cause an eccentricity between the two impellers.

The fact that the retarder cooperates with the wind turbine means that two fluid machines having the same basic characteristic that the generated or absorbed output changes parabolicly with respect to the rotational speed. Means In the known retarder, such a situation means a control in which the maximum value of the braking torque or the braking output of the retarder is always fixedly set. By virtue of its unique characteristics, this causes the retarder to absorb only a small amount of power if the wind power plant can generate only a small amount of power.

Other controls, for example for safety reasons, do not require continuous operation apart from completely draining the casing.

Furthermore, methods are known for operating retarders in various operating states by means of pressure control, ie by influencing an annular working space surrounded by a fixed impeller and a rotary impeller. .

It must also be taken into account that, depending on the operating situation to be achieved, that is to say for example to obtain a constant braking torque over a wide rotational speed range, the typical diameter of the retarder must be relatively large. Goodbye. This has a detrimental effect when using retarders in vehicles, especially with regard to overall height and weight.

[0008]

The problem on which the invention is based is to improve a retarder of the known type in such a way that it is possible to adapt it to various operating situations with simple measures and at a minimum technical cost. To do.

[0009]

According to the present invention, this problem is solved by *.

By adjusting the mutual positions of the two impellers of the fluid retarder, a retarder adjusting device with little pressure interference is achieved. The fixed impeller is configured such that the fluid force acting on the blade row is converted into a braking torque as a reaction force and at the same time converted into a tangential force proportional to the braking torque. In this case, the fixed impeller produces a force that tends to move the impeller to an eccentric position with respect to the rotary impeller.

The fixed impeller is associated with an adjusting means, which produces an adjusting force opposite to the force exerted by the fixed impeller. In this way, by varying the pressure acting on the adjusting means, the fixed impeller is moved to any predetermined position with respect to the axis of the rotary impeller, and thus a predetermined braking torque is produced. Will be possible.

The force derived from the fixed impeller on the basis of the braking torque is in balance with the adjusting force of the adjusting means. Therefore, this adjusting force represents the magnitude of the generated braking torque. Thus, the adjustment of the braking torque concerns only the formation of the variable adjustment force. This makes the retarder adjustment extremely simple.

Claims 2 and below describe advantageous configurations of the invention.

According to claims 2 to 4, the fixed impeller is guided by longitudinal guide means, which guide means is directly provided with adjusting means which is constructed as a piston-cylinder unit with an adjusting piston. It is working. In order to obtain a tangential force proportional to the braking torque, in the vicinity of the reference plane passing through the center of the fixed impeller with respect to the longitudinal axis of the linear guide means, on one side of the blade row of the fixed impeller,
A vaneless region is provided, and in the vaneless region,
At least one blade is missing. This causes an imbalance of the tangential force parallel to the axis of the vertical guiding means, and a force proportional to the resulting braking torque is generated along the axis of the vertical guiding means. Become.

In the fifth and sixth aspects, the fixed impeller is
It is capable of turning around a center of rotation located outside the blade row. The braking torque generated in the stator-blade row effectively acts also as the rotation torque around the rotation center point located outside the stator. Also in this embodiment, in connection with the fixed impeller, adjusting means are provided which are configured as cylinders with adjusting pistons. Therefore, the variable adjustment pressure enables the swivel movement of the fixed impeller around the eccentric center of rotation.

Claims 7 to 9 show other structural features. At one end position of the adjusting means, the fixed impeller concentrically faces the rotary impeller. In this case, when the force generated by the adjusting pressure of the adjusting means is larger than the force generated by the braking torque of the fixed impeller, the aligned state of both impellers is always achieved. The minimum braking torque is obtained when the casing is drained and the fixed impeller occupies an extremely out-of-turn swivel position, so that only air circulation takes place in the braking casing. This state is necessary for safety reasons.

[0017]

[Operation] Based on the braking torque generated in the fixed impeller,
Expressing the magnitude of the braking torque, a force used as a characteristic value for torque control is obtained.

[0018]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 schematically shows a retarder (1) with a casing (2).

A drive shaft (not shown) is provided in the casing (2).
A rotary impeller (3) connected to the casing faces a fixed impeller (4) which is non-rotatably provided in the casing (2).
The blade rows facing each other form an annular working space that can be filled with the working fluid. Fixed impeller (4)
Can be eccentrically moved in the vertical direction with respect to the rotation axis (5) of the rotary impeller (3) along the vertical axis (11) by the vertical guide means (10). In this case, the fixed shaft (6) is aligned with the rotating shaft (5) at one end position of the guide means (10).

The longitudinal guide means (10) has an adjusting means (12).
Are combined. The adjusting means (12) comprises a cylinder (13) with a piston (14) and is controllable by a variable pressure pst.

The pressure source (16) configured as a pump is connected to the control-adjusting means (15), the control-adjusting means being the same.
(15) produces a variable adjustment pressure according to a control command from the outside. The drive medium can be the working fluid of the retarder or the compressed air of the braking system in a vehicle retarder, for example.

The blade row (7) of the fixed impeller (4) is provided with a bladeless region (9). This vaneless area (9)
It is located on one side of the blade row (7) in the reference plane (8) which passes through the fixed shaft (6) and is associated with the axis (11) of the longitudinal guide means (10). This causes the blade row (7) to be asymmetric on both sides of the axis (11).

When the rotary impeller (3) rotates in the direction of the arrow,
An unbalanced reaction force in the direction of the axis (11) is generated in the bladeless region (9) (the rotary impeller (3) is shown in an open state). This unbalanced reaction force tends to push the fixed impeller (4) from a position concentric with the rotary impeller (3). This reaction force is a force that is directly proportional to the braking torque.

In order to move the fixed impeller (4) to a predetermined position with respect to the rotary impeller (3) and generate a predetermined braking torque according to its eccentricity, the adjusting means (12) is used. , It is necessary to generate a corresponding counter force. This force balance is achieved by the piston (14) with a variable adjustment pressure. The maximum torque is always generated when the rotating shaft (5) and the fixed shaft (6) are aligned when the rotation speed is constant.

As the eccentricity increases, the braking torque becomes smaller and the counterforce of the adjusting means (12) required to hold the fixed impeller (4) in place becomes smaller. In order to achieve a constant transition of the braking torque by shifting the force balance position by the variable adjustment pressure pst,
The operating point can be easily changed over a wide characteristic range.

FIG. 2 shows the retarder according to FIG. 1, in which the fixed impeller (4) is moved to the other limit position by means of the longitudinal guide means (10). Fixed impeller (4)
Are offset by the radial height of the vanes, where the braking torque is substantially minimal.

3 and 4 show another structure of the adjusting means. The fixed impeller (4) is rotatably supported at a rotation center (17) located outside the blade row (7). The blade row (7) of this fixed impeller does not have a bladeless region. The generated torque is also effective at the eccentric rotation center (17), and acts on the fixed impeller (4) in the rotation direction of the rotary shaft. This causes eccentricity of the impellers.

Via the adjusting means comprising the cylinder (13) and the piston (14), the fixed impeller (4) is moved to the position to be adjusted on the basis of the variable adjusting pressure pst acting on the lever (18). be able to. The fixed impeller (4) swivels in the W direction. In this case, again, in one end position, the axes (5) and (6) of the impellers (3) and (4) are aligned, and in the other end position, as in the embodiment of FIG. In addition, the eccentric distance corresponds to the height of the blade.

If the working space is full, the end position is not sufficient to reduce the braking torque. For example, for safety reasons, drain means (19) are used in both embodiments. The casing (2) can be drained.

FIG. 5 shows the characteristics of this retarder and shows the change of the braking torque M with respect to the rotation speed n of the rotary impeller. Curve a is the braking torque curve of a known pressure-controlled retarder. From the zero point to the operating point B, the torque changes parabolically. From there to driving point A,
There is a gradual transition to a nearly constant braking torque.

If the retarder is designed to include the operating point A, that is, to obtain the maximum torque at the minimum rotation speed, a typical dimension corresponding to the parabola up to the operating point B, that is, a relatively large dimension, is obtained. It necessarily has a large diameter, high weight, and large external dimensions.

According to the invention, the operating point A is adjustable. By controlling the torque directly, a horizontal adjustment curve c, d is possible, which is a relatively gentle parabola b between the zero point and the operating point A. Because it is limited. This relatively gentle parabola b corresponds to a relatively small representative diameter of the retarder, which gives a relatively advantageous retarder size.

In this case, the parabola b corresponds to the aligned state of the rotary shaft (5) and the fixed shaft (6). When the eccentricity of each axis increases, the parabola e that is relatively gentle with respect to the braking torque
~ H occurs. In this case, the parabola h corresponds to the maximum eccentricity. The transition at this time is constantly performed steplessly.
Since the adjusting pressure pst is directly proportional to the braking torque M, the adjusting force of the adjusting piston, that is to say the adjusting pressure pst, is likewise constant, for example along the adjusting curve c. However, as a result, the eccentricity is variable even when the adjustment pressure pst is constant and the braking torque is constant.

When braking is started during high speed rotation, first, the eccentricity between the rotary shaft (5) and the fixed shaft (6) is set to a large value at a predetermined adjusting pressure. When the rotation speed decelerates, the eccentricity decreases, and the braking torque shifts to the parabola g to e. When the axes are engaged, the steepest parabola b passing through the design point A is reached. The process of automatically reducing the eccentricity is a balance pendulum process that automatically proceeds.

The flow state in the retarder and the degree of fluid contact with the blade row (7) of the fixed impeller are properly controlled. As a result, when the rotational speed is high, the rotational speed is low and the blade rows are significantly overlapped, that is, the eccentricity is relatively small,
In order to generate the same braking torque as when they are substantially aligned, it is sufficient that the blade rows overlap slightly, that is, the eccentricity is increased.

[0036]

The external dimensions are reduced, the weight is reduced, and the braking torque can be easily adjusted.

[Brief description of drawings]

FIG. 1 is a schematic view of a fluid retarder with stator guide means in one end position.

FIG. 2 is a schematic view of a fluid retarder with stator guide means in the other end position.

FIG. 3 is a schematic view of a fluid retarder including a fixed impeller that can swivel.

FIG. 4 is a schematic diagram of a fluid retarder with a swivel fixed impeller.

FIG. 5 is a diagram of various characteristic curves for comparison.

[Explanation of symbols]

(1) Fluid type retarder (2) Casing (3) Rotating impeller (4) Fixed impeller (5) Rotating shaft (6) Fixed shaft (7) Blade row (8) Reference plane (9) Bladeless area (10 ) Guide means (11) Axis (12) Adjusting means (13) Cylinder (14) Piston (15) Control adjusting means (16) Pressure source (17) Center of rotation (18) Lever (19) Drain means

Front Page Continuation (72) Inventor Klaus Vogelsank Germany Day 7180 Crailsheim Wilhelm von Kettererstrasse 17

Claims (9)

[Claims] 1. A fixed casing capable of being filled with a working fluid, a rotary impeller connected to a drive shaft, and a fixed impeller movable to move out of a concentric position with respect to the rotary impeller. The fluid retarder is provided with an adjusting means (12) for moving the fixed impeller (4) to an eccentric position, and at each position of the fixed impeller (4), a braking reaction acting on the fixed impeller (4). A hydrodynamic retarder, characterized in that a balance is maintained between the force and the opposite adjusting force exerted by the adjusting means (12). 2. The fixed impeller (4) has a linear guide means (1).
Fluid retarder according to claim 1, guided by 0). 3. A linear guide means (10) for adjusting piston
Adjusting means (1) configured as a cylinder (13) with (14)
3. The fluid retarder according to claim 1, which is directly connected to 2). 4. The blade row (7) of the fixed impeller (4) is orthogonal to the axis (11) of the linear guide means (10) and is fixed to the fixed shaft (6) of the same impeller (4). The fluid retarder according to any one of claims 1 to 3, wherein at least one blade is reduced on one side of the blade row (7) near the passing reference plane (8). 5. The fixed impeller (4) according to claim 1, wherein the adjusting means (12) allows it to swivel about a center of rotation (17) which is off the fixed axis (6). 4. The fluid type retarder according to any one of 4 to 4. 6. Cylinder (13) of the adjusting means (12) is controlled-
A pressure source (16) in communication via the adjusting means (15), whereby the pressure acting on the adjusting piston (14) of the adjusting means (12) can be adjusted. 1 to 5
The fluid-type retarder according to any one of 1 to 3 above. 7. The fixed impeller (4) in the casing (2) at one end position of the adjusting means (12) is a rotary impeller.
The fluid type retarder according to any one of claims 1 to 6, which concentrically faces (3). 8. When the maximum pressure is supplied to the cylinder (13) of the adjusting means (12), the fixed impeller (4) turns into a rotating impeller (3).
8. A hydraulic retarder according to any of claims 1 to 7, adapted to reach a position concentric with respect to. 9. The casing according to claim 1, wherein the casing (2) having a working space between the rotary impeller (3) and the fixed impeller (4) is drainable. The described fluid retarder.