JPH03260421A - Speed change gear of fluid joint - Google Patents

Abstract

PURPOSE:To shorten speed change time remarkably from the maximum number of revolution to the minimum number of revolution or from the minimum number of revolution to the maximum number of revolution by providing a valve, which opens or closes an oil exhaust port by the differential pressure of working fluid, on the periphery of the impeller or the impeller casing of the fluid joint coupled to a driving shaft. CONSTITUTION:In the stoppage condition before start or in the condition that only the driving shaft 1 is rotating, neither working fluid nor valve working fluid is supplied. Next, when the driving shaft 1 rotates in the condition that the working fluid is supplied from a hole E into the circuit formed by an impeller 2 and a runner 3, and that valve working fluid is supplied to the valve 8 which is provided on the periphery of the impeller 2 or the impeller casing 5 and opens or closes by the differential pressure of working fluid, the valve 8 closes completely the oil exhaust port B of working fluid inside the circuit by the difference between the force operating in the closing direction by the valve working fluid acting on the valve 8 and the force working in the opening direction by the working fluid inside the circuit, and rotates the driven shaft 4 at the maximum number of revolution.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a transmission mechanism for a fluid coupling, and more particularly to a transmission device that shortens the shifting time of an oil-fill/discharge type transmission mechanism.

Conventionally, there are two types of fluid couplings: one is a fixed-filling type that operates with one circuit always filled with fluid (hydraulic oil), and the other is a type that operates with fluid (hydraulic oil) constantly filled in one circuit, and a type that changes the transmission torque capacity by adjusting the amount of fluid (hydraulic oil) in the circuit. There is a variable filling type that can be used, and the variable filling type includes a variable speed type and an oil filling/discharging type.

FIG. 9(a) is a schematic diagram of the variable coupling type fluid coupling, showing an impeller (pump impeller) 102 connected to a drive shaft 101 and a runner (turbine impeller) connected to a driven shaft 104. 103 are mounted facing each other to form a fluid circuit, and the hydraulic oil in the circuit passes through an oil tank 105, an oil pump 106, and an oil cooler 107, and then reaches the operating device 10.
It is possible to partially replace (increase or decrease) via a scoop tube 109 operated by 8.

This functions for the purpose of controlling the rotational speed of the driven motor and starting the drive-side electric motor without load, and has the effect of reducing running costs and driving machine costs.

FIG. 9(b) is a schematic diagram of the above-mentioned oil charging/discharging type fluid joint, in which the hydraulic oil in the circuit flows into the circuit via the charging/discharging oil switching valve 111 connected to the outlet of the oil cooler 107. Oil is charged and drained through the replenishment pipe 112 or the return pipe 113 to the oil tank 105, and the oil in the circuit is constantly passed through the nozzle 114.
The oil is returned to the oil tank 105 in fixed amounts.

This device functions to cut off power (clutch action), absorb torsional vibration, start the prime mover without load, and reduce starting resistance, allowing independent operation of the engine, on/off operation of the driven machine, and easy starting of the prime mover. It has effects such as acceleration.

FIG. 9(c) is a schematic diagram of the constant speed type (constant filling type) fluid coupling, which is operated with the circuit always filled with fluid. This functions to reduce starting resistance, reduce and absorb vibrations and shocks, absorb torsional vibrations, and act as a torque limiter, and has the effect of protecting the motor and connecting equipment.

[Problem to be solved by the invention]

The above-mentioned conventional variable joint fluid coupling (Fig. 9(a)) is as follows:
Any rotation speed can be set by changing the position of the scoop tube 109, and the rotation speed control range is wide and suitable for multi-purpose operation, but the speed change response speed between the maximum and minimum rotation speeds is not fast. It took about 10 seconds.

In addition, the oil charging/discharging type fluid coupling (FIG. 2(b)) switches only two points, the maximum rotation speed and the minimum rotation speed, by opening and closing the oil charging/discharging switching valve 111. However, when the driven machine is operated, hydraulic oil is constantly discharged from the nozzle 114, which reduces efficiency in small models, and there is a limit to the amount of hydraulic oil discharged from the nozzle 114. Therefore, there was a problem that the speed change response speed was slow.

Further, a constant speed type fluid coupling (FIG. 3(C)) is mainly suitable for absorbing and mitigating impact force, but cannot control speed.

Therefore, if these conventional structures are applied to equipment that performs intermittent operation such as descaling pumps used to remove scale from the surface of steel materials being manufactured in steel factories, the speed change response speed is slow, making it extremely difficult to put them into practical use. The problem was that it was difficult.

For this reason, during no-load operation, the driven shaft was operated continuously at maximum rotational speed and throttled by a valve, etc.

An object of the present invention is to solve the above-mentioned problems of the prior art and to significantly improve the speed change response speed from the highest rotational speed to the lowest rotational speed and from the lowest rotational speed to the highest rotational speed of the transmission mechanism of a fluid coupling. Furthermore, the purpose is to set the rotational speed control range to two points, the maximum rotational speed and the minimum rotational speed, and to enable the minimum rotational speed to be set depending on the application.

[Means for Solving the Problems] In order to achieve the above-mentioned problems, the present invention creates an oil drain hole in the outer periphery of the impeller or impeller casing of a fluid coupling connected to the drive shaft using a differential pressure of hydraulic oil. It is characterized by a valve that opens and closes so that oil can be charged and drained in a short time.In addition, a dam (dam) is installed near the oil drain hole in the impeller casing, usually inside, and the shape of the dam allows for a minimum It is characterized by being able to set the rotation speed.

[For production]

Since the present invention is configured as described above, neither hydraulic oil nor valve hydraulic oil is supplied in a stopped state before starting or in a state in which only the drive shaft is rotating.

Next, hydraulic oil is supplied into the circuit formed by the impeller and the runner, and the valve is driven with the hydraulic oil supplied to a valve that is provided on the outer periphery of the impeller or the impeller casing and opens and closes depending on the differential pressure of the hydraulic oil. When the shaft rotates, the valve closes the drain hole for the hydraulic oil in the circuit due to the difference between the force acting on the valve in the closing direction due to the valve hydraulic oil and the force acting in the opening direction due to the hydraulic oil in the circuit. Fully close and rotate the driven wheels at maximum speed.

Next, when the supply of valve hydraulic oil is stopped, the force acting in the direction of closing the valve becomes zero, while the pressure of the hydraulic oil in the circuit acting in the direction of opening the valve instantly fully opens the valve. Therefore, the hydraulic oil in the circuit is drained from the oil drain hole in an extremely short time.

At this time, near the oil drain hole in the impeller casing,
A minimum speed setting dam, usually located at the front, keeps the hydraulic fluid in the circuit at the level of the dam, and the driven wheels are operated at a minimum speed.

In this way, by opening and closing the above valve (control valve),
The driven wheels can shift between two operations at the highest and lowest rotational speeds in a very short time.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a longitudinal cross-sectional view showing the upper half of a fluid coupling equipped with a transmission mechanism, showing one embodiment of the present invention.

In the figure, an impeller 2 is attached to a drive shaft 1, and a runner 3, which constitutes a fluid circuit, is attached to a driven shaft 4 in opposition to the impeller 2. An impeller casing 5 surrounding the outer periphery of the runner 3 is attached to the impeller 2, and the impeller casing 5 further includes an inner casing 6 on the side and a valve seat 7 on the radially outer side of the oil drain hole B.
A valve body (valve disk) 8 and a valve cover 9 are respectively attached.

A valve operating pressure chamber 9a is formed by the inner surface of the valve cover 9 on the side of the valve body 8 opposite to the valve seat, and the radially outer side of the pressure chamber 9a is opened to the outside through a small hole C. The inside communicates with a hydraulic oil supply nozzle 10 attached to the bearing casing 11 . Note that the oil supply nozzle 10 is omitted, and the valve hydraulic oil supply hole F is bypassed from the hydraulic oil supply chamber E formed in the bearing casing 11.
The hydraulic oil for the valve body 8 may be supplied from the above.

On the other hand, the runner 3 has a hydraulic oil supply chamber E on the inside in the radial direction.
A hydraulic oil supply hole A is provided in the impeller casing 5, and the impeller casing 5 is provided with the oil drain hole B and the oil drain hole B.
A minimum rotation speed setting dam D is provided axially inwardly so as to protrude radially inwardly. In addition, 12 in the figure
is a bearing.

Next, the effect will be explained.

(1) In a pre-start stopped state or a state in which only the drive shaft 1 is rotating, as shown in FIG. Neither valve operating oil is supplied, and the valve body 8 opens the oil drain hole B.

(ii) Next, while the drive shaft 1 is being driven, the hydraulic oil is supplied to the oil supply chamber E.
When the circuit is filled through the oil supply hole A and the valve operating oil is supplied from the oil supply nozzle 10 to the pressure chamber 9a on the back side of the valve body 8 (on the right side in the figure), as shown in FIG. As shown in FIG. 3a, which is an enlarged view, the valve seat 7 is quickly closed, the circuit is filled with hydraulic oil as shown by the diagonal lines, and the driven shaft 4 rotates at 100% speed.

At this time, the force F acting in the direction of closing the valve body 8 in FIG. =γ/2g×ω
"xR" xi/10A1 Pressure-receiving area T on the back surface of the two valve bodies 8 (right side in the figure): Specific gravity of the hydraulic oil ω: Rotation angular velocity of the impeller 2 R: Radius of the valve body 8 On the other hand, it acts in the direction of opening the valve body 8 The force F2 is F, = P,
XA2... ■Here, F2 is the pressure that acts in the direction of opening the valve body 8, F2 = r/2gxω2xR2
×1/10A2: Pressure-receiving area of the front surface of the valve body 8 (left side in the figure) From both formulas, F+ Fz = P + XAI P z X
AzHere, if the small hole C, pressure receiving area A, and A2 are determined so that P, XAI -F2 XA2 >O, then F
+ Fz>O, that is, F + > F! and valve body 8
is fully closed.

In this state, a small amount of valve hydraulic oil q1 is constantly leaking from the small hole C, but the valve hydraulic oil Q becomes Q+>q+.
1 is supplied, the pressure drop of P is small.

(iii) Next, as shown in FIG.
When the supply of valve hydraulic oil from 0 is stopped, a force F acting in the direction of closing the valve body 8, as shown in the enlarged view of FIG.
, becomes zero, and the force F2 acting in the direction of opening the valve body 8 is:
F z = P z XA> Or:, therefore, F2>F,
Therefore, the valve body 8 will be opened at the next moment as shown in FIG.

(iv) In the state shown in FIGS. 5 and 5a above, the valve body 8 is open, the hydraulic oil (indicated by diagonal lines in the figure) is maintained at the level of the lowest speed setting dam D, and the remaining The driven shaft 4 is discharged as shown by the arrow and operated at the minimum rotation speed.

The system of the above-mentioned hydraulic oil and valve hydraulic oil will be explained with reference to Figs. 6 to 8. Fig. 6 shows a basic system diagram, in which hydraulic oil is pumped from oil tank a through strainer b to oil pump C. and valve hydraulic oil are supplied, and a relief valve d for oil pressure adjustment and an oil cooler e are installed as necessary.

When the control valve f is fully open, both hydraulic oil and valve hydraulic oil are supplied, the valve body 8 in FIG. 1 is closed, and the driven shaft 4 is operated at the maximum rotation speed (FIGS. 3 and 3a).

When the control valve f is fully opened from this state, the valve operating oil (
Indicated by dashed lines in the figure. ) is not supplied, the valve hydraulic oil is discharged from the small hole C in FIG. Operated at minimum rotation speed. That is, the state shown in FIGS. 5 and 5a is reached through the states shown in FIGS. 4 and 4a.

When the control valve f is fully opened again from this state, both the hydraulic oil and the valve hydraulic oil are supplied, the valve body 8 shown in FIG. 1 is opened, and the driven shaft 4 is operated at the maximum rotation speed.

In this way, by opening and closing the control valve f, the driven shaft 4
The system transitions between the two operations of maximum rotation speed and minimum rotation speed in a very short time.
・Repeat the action.

Oil in the bypass line to perform heat exchange of the hydraulic oil when the control valve f is fully open! Via the adjustment orifice h,
Supply an appropriate amount of hydraulic oil. The bypass line can be omitted if the operating time at the lowest rotational speed is short, or if the working oil calorific value at the lowest rotational speed is small.

FIG. 7 is an example of a system in which the control valve f in FIG. 6 is divided into a hydraulic oil control valve f and a valve hydraulic oil control valve g for the purpose of improving and adjusting responsiveness.

FIG. 8 shows the simplest system that is applied when the power is small. In this case, the oil supply nozzle IO shown in FIG. 1 is unnecessary, and the valve hydraulic oil is supplied from the valve hydraulic oil supply hole F branching from the hydraulic oil supply chamber E.

〔Effect of the invention〕

As explained above, according to the present invention, a valve that opens and closes the oil drain hole using the differential pressure of the hydraulic oil is provided on the outer periphery of the impeller or impeller casing of the fluid coupling connected to the drive shaft, and the valve can be filled in a short time. By draining the oil, the shift time can be significantly shortened from the highest rotational speed to the lowest rotational speed and from the lowest rotational speed to the highest rotational speed.

In addition, a dam is installed inside the oil drain hole in the impeller casing, and the shape of the dam allows the minimum rotation speed to be set depending on the application. For example, a pump for a descaling device or the like can be operated at the minimum rotation speed during no-load operation, and a great energy saving effect can be obtained with simple control.

[Brief explanation of drawings]

Fig. 1 Fig. 2 is a longitudinal cross-sectional view showing different operating states of a fluid transmission equipped with a transmission mechanism according to an embodiment of the present invention, Fig. 3, Fig. 4, and Fig. 5 are operation explanatory diagrams. , Fig. 3a, Fig. 4
Figure a and Figure 5a are action explanatory diagrams showing the main parts enlarged;
6, 7, and 8 are different system diagrams of hydraulic fluid and valve hydraulic fluid, and FIGS. 9(a), 9(b), and 9(c) are explanatory diagrams of a conventional fluid coupling. 1... Drive shaft, 2... Impeller, 3... Runner,
4... Driven shaft, 5... Impeller casing, 6...
・Internal casing, 7... Valve seat, 8... Valve body, 9.
... Valve cover, 1゜... Oil supply nozzle, 11... Bearing casing, A... Hydraulic oil supply hole, B... Oil drain hole,
C: Small hole, D: Minimum speed setting dam, E: Hydraulic oil supply chamber, F: Valve hydraulic oil supply hole. Fig. 1 Fig. 3a Fig. 1 Fig. r5a Fig. 6 □ I 乍壷力〉由bulb made by Umari fig. ---Valve made I7I gon

Claims (1)

[Claims] 1. In a transmission mechanism of a fluid coupling, a valve is provided on the outer periphery of the impeller or impeller casing of the fluid coupling connected to the drive shaft to open and close the drain hole using a differential pressure of the hydraulic fluid. A transmission device for a fluid coupling, characterized in that oil is charged and drained in a timely manner, and the shift time from the highest rotational speed to the lowest rotational speed and from the lowest rotational speed to the highest rotational speed is significantly shortened. 2. The transmission device for a fluid coupling according to claim 1, wherein a dam is provided inside the oil drain hole in the impeller casing, and the minimum rotation speed can be set by the shape of the dam.