KR20000033694A - Forward/backward movement controlling system of power trnsmission system - Google Patents

Abstract

PURPOSE: A forward/backward movement controlling system of power transmission system is provided to stably maintain forward/backward moving or neutral states without concerning to vibration or shaking of a vehicle or a ship. CONSTITUTION: A forward/backward movement controlling system of power transmission system comprises a forward/backward moving solenoid valve(39) and an accumulator(68) installed therein. The solenoid valve(39) is installed on a pressure line(32) between a direction converting valve(38) and a valve(30) and alternatively controls the direction converting valve(38) to left/right direction. The accumulator(68) is installed on a forward/backward movement pressure lines(58,62) connected to the direction converting valve(38) from forward/backward movement clutches(56,60) by forming a confluent pressure line(66) by using a shuttle valve(64). The forward/backward moving solenoid valve(39) has a forward moving solenoid valve(40) and a backward moving solenoid valve(44). The forward moving solenoid valve(40) is connected to a forward movement side hydraulic part of the direction converting valve(38) through a forward movement signal line(42). The backward moving solenoid valve(44) is connected to a backward movement side hydraulic part of the direction converting valve(38) through a backward movement signal line(44).

Description

Forward and Backward Control of Power Train

The present invention relates to a forward and backward control device for a power transmission device, and more specifically, to electrically control the hydraulic pressure acting on the clutch to maintain a stable forward, backward or neutral state regardless of vibration or shaking of the vehicle or ship. It relates to a forward and backward control device of a power transmission device that can be.

In general, industrial vehicles or ships, such as heavy equipment, are equipped with a power train for transmitting the power generated from their engines to the drive wheels or propulsion shafts, and such power trains basically transmit or block power from the engine. And a transmission provided between the clutch and the propulsion shaft to switch the rotational force and the speed to suit the driving state of the vehicle or the ship, and transmit the power of the engine to the propulsion shaft. On the other hand, the transmission employed in the power transmission device of such heavy equipment or ships is shifted to neutral, forward and / or forward by the operation lever.

A hydraulic circuit diagram showing a schematic configuration and operation of such a conventional power transmission device is shown in FIG. According to Fig. 1, the conventional power transmission device is operated in accordance with the operation of the engine in the case of the engine type or in the case of the electric type, according to the operation of the motor 1, the hydraulic pump 2 connected to the operating source is operated so that the hydraulic oil is main It is sent out via line (3). The pressurized oil sent in this way is supplied to a torque converter (not shown) through the main relief valve 4 to amplify the torque and transmit the torque to the drive shaft. In addition, the main line 3 is connected to an inching valve 5 which is operated and switched by the stepping force of the clutch pedal 5a. The inching valve 5 is connected with two inching hydraulic lines 7a and 7b for flowing the pressurized oil discharged therefrom, and one of the inching hydraulic lines 7b has an auxiliary clutch 8 connected thereto. Interrupt the pressure oil flowing through the line. In addition, the inching hydraulic line 7a is further supplied to the accumulator 9 for accumulating the hydraulic oil flowing therefrom, branching into two lines again. On the other hand, the other inching hydraulic line 7b connected to the inching valve is directly connected to the hydraulic oil line 10 drawn out from the accumulator 9. The pressure oil supplied through the pressure oil line 10 is supplied to the direction switching valve 11 in communication with the pressure oil line. On the other hand, an operation lever 12 is connected to the directional valve 11 to actually select the hydraulic oil applied to the clutch described later by moving the spool built in the directional valve. On the other hand, the positioning ball device 13 is provided between the directional limit valve and the operation lever. The positioning ball device 13 moves the operation lever 12 due to the shaking and vibration of the vehicle or the inattention of the driver. This is to prevent inadequate shifting. In addition, when the operation lever 12 is operated in the forward direction, the direction switching valve 11 is provided with a forward clutch 15 through which hydraulic pressure is applied through the forward signal line 14, and the operation lever is moved in the reverse direction. When operated, a reverse clutch 17 is installed through which the hydraulic pressure is applied through the reverse signal line 16. Of course, when the operation lever 12 is positioned in the neutral position, a separate drain line communicating with the oil pressure line 10 is provided without the oil pressure being supplied through the respective forward and backward signal lines 14 and 16. Is formed in the hydraulic is not to act on the clutch.

However, it has been shown that some problems arise in such a conventional forward and backward transmission.

That is, although the operating lever is moved by the carelessness of the driver or the operating lever is moved by the shaking, vibration, or impact of the vehicle, and the operation of the clutch is prevented, the operating lever has a positioning ball device 14. Although it is installed, the positioning ball device 14 may cause abnormal wear or breakage due to frequent operation of the operation lever, and in this case, there is a problem in that the driver cannot maintain a predetermined shift state.

In addition, when the above-mentioned phenomenon is caused, the driver has to be inconvenient to hold the operating lever by hand, and furthermore, even when the operating lever is in the neutral position, even though each clutch does not operate the friction plate of the clutch. Due to fluid viscosity and fluid rotational flow between the disk and the disk, a drag phenomenon occurs, which causes the output shaft to rotate, thereby causing undesired driving of a vehicle or a ship, which adversely affects safety and operability. .

Accordingly, the present invention has been invented to solve the above-described problems, and an object of the present invention is to provide a power that can optimally maintain a forward, backward or neutral state regardless of vibration, shaking, or carelessness of the vehicle when the operation lever is operated. It is to provide a forward and backward control device of the delivery device.

Another object of the present invention is to control the forward and backward control of the power transmission device which can prevent the operation of the clutch by dragging the hydraulic pressure is formed in the inching hydraulic line and the auxiliary clutch even when the operating lever is in the neutral position. To provide a device.

Another object of the present invention is to provide a power transmission having two pistons and two spools, and having a directional valve capable of stably maintaining a predetermined switching state among forward, backward or neutral by using a hydraulic pressure and a hydraulic pressure area difference. It is to provide a forward and backward control device.

1 is a hydraulic circuit diagram showing the configuration and operation of the forward and backward control device of the conventional power transmission device.

Figure 2a and 2b is a hydraulic circuit diagram of one embodiment and another embodiment showing the configuration and operation of the forward and backward control device of the power transmission device according to the present invention.

Figure 3 is a cross-sectional view showing the configuration of the direction switching valve applied to the power transmission device according to the present invention.

♣ Explanation of symbols for the main parts of the drawing ♣

20: motor 22: hydraulic pump

24: mainline 28: clutch pedal

30: inching valve 32, 34: inching hydraulic line

38: Directional Valve 40: Forward Solenoid Valve

42: Forward signal line 44: Reverse solenoid valve

46: reverse signal line 48: forward piston

50: reverse piston 52: forward spool

54: reverse spool 56: forward clutch

60: reverse clutch 68: accumulator

These objects include a hydraulic pump for sending pressure oil, a main line for supplying the pressure oil discharged by the hydraulic pump, an inching valve connected to the main line to control the pressure oil, and to be switched by the pedal force of the clutch pedal. A forward clutch to which the inching hydraulic line connected to supply the pressurized oil from the inching valve to the inching clutch, the directional valve for switching the pressure oil from the inching hydraulic line, and the pressurized oil supplied from the directional valve are applied. And a forward and backward control device of a power transmission device including a reverse clutch, wherein the forward and backward solenoid switches the left and right direction switching control on the inching hydraulic line between the direction switching valve and the inching valve in accordance with a forward and backward signal. Interposed through the valve, the forward and reverse clutch supplied from the direction switching valve And reverse hydraulic lines may be achieved by a forward-reverse control apparatus for a power transmission system, characterized in that to install the accumulator to form a hydraulic line joining the shuttle valve.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2a and 2b is a hydraulic circuit diagram showing one embodiment and another embodiment of the forward and backward control device of the power transmission device according to the present invention, Figure 3 is shown in the forward and backward control device of the power transmission device according to the invention A cross-sectional view showing in detail the configuration and operation of the divert valve applied is shown.

The power transmission device according to the present invention basically supplies a hydraulic pump 22 which is operated by a motor 20 driven by the operation of an engine of a vehicle or a ship, and delivers the hydraulic oil, and the hydraulic oil output by the hydraulic pump. And a main relief valve 26 provided in a line for supplying the hydraulic oil in the main line 24 to a torque converter (not shown). The main line 24 further includes a main relief valve 26. The inching valve 30 which is actuated and switched by the stepping force of the clutch pedal 28 is connected. The inching valve 30 is connected with two inching hydraulic lines 32 and 34 for flowing the hydraulic oil discharged therefrom, and one of the inching hydraulic lines 32 is connected with the inching clutch 36. Interrupt the pressure oil flowing through the line. On the other hand, the other inching hydraulic line 34 is joined after the inching clutch 36 of one inching hydraulic line 32. In addition, the inching hydraulic line 32 is provided with a directional valve 38 for controlling the actual supply of pressure oil to the forward and backward clutches, which will be described later.

In particular, the direction switching valve 38 is provided with a forward and backward solenoid valve 39 in communication with the inching hydraulic line 32, as shown in Figures 2a and 2b, the forward and backward solenoid valve 39 It consists of a forward solenoid valve 40 and a reverse solenoid valve 44. Here, the forward solenoid valve 40 is connected to the forward pressure receiving portion of the direction switching valve 38 through the forward signal line 42, the reverse solenoid valve 44 is directed through the reverse signal line 44 It is connected to the reverse pressure receiving part of the selector valve 38. In addition, a reverse solenoid valve 44 communicating with the inching hydraulic line 32 is connected by an electric reverse signal line 46. Here, each of the solenoid valves (40, 44) serves to control the hydraulic pressure acting on the direction switching valve 38, and also to control the hydraulic supply of the forward and backward, respectively.

Further, the directional valve 38 is supplied from the inching hydraulic line 32 in the same manner as the forward piston 48 interlocked by the operation of the pressure oil or the forward solenoid valve 40 supplied from the inching hydraulic line 32. The reverse piston 50 is interlocked by the operation of the pressure oil or the reverse solenoid valve 44, and the forward piston 48 is connected to the forward spool 52, and similarly to the reverse piston 50. The reverse spool 54 is linked.

In this way, the direction switching valve 38 is actually connected with a hydraulic line for supplying the control and the hydraulic pressure controlled therefrom to each clutch, that is, the forward hydraulic line 58 for actuating the hydraulic pressure on the forward clutch 56. ) And a reverse hydraulic line 62 for applying hydraulic pressure to the reverse clutch 60. In addition, a shuttle valve 64 is provided in each of the hydraulic lines 58 and 62 between the directional valve 38 and the respective clutches 56 and 60. The shuttle valve 64 has two inlets for each hydraulic line 58, 62 from the direction change valve 38 to the respective clutches 56, 60. It selects the inlet and takes the hydraulic pressure from the inlet and supplies it to the accumulator 68 through the joining hydraulic line 66 to be accumulated there. Of course, the direction switching valve 38 is connected to the drain line 70 for draining the hydraulic oil when the operating lever is neutral.

Referring to the operation of the forward and backward control device of the power transmission device according to the present invention configured as described above, first, in the neutral state, the pressure oil of the inching hydraulic line 32 is the forward pistons 48 and 50 of the directional control valve 38. And through the inner hole of the reverse piston 50 so that each of these pistons are pushed to both sides. As such, when the respective pistons 48 and 50 are pushed to both sides, the inching hydraulic line 32 does not communicate with both the forward hydraulic line 58 and the reverse hydraulic line 62, so that the forward clutch 56 transmits rotational force. And it is to maintain the neutral state so that the hydraulic pressure required for the forward and reverse to both the reverse clutch 60 is not applied. Of course, since the hydraulic pressure is formed in the inching clutch 36 and the inching hydraulic line 32 in this neutral state, drag phenomenon is prevented in the forward and backward clutches 56 and 60, thereby preventing the vehicle or the ship from being driven in the neutral state. I will back.

Then, when the driver switches to the forward direction, the electric signal is input to the forward solenoid valve 40 associated with the direction switching valve 38 to generate the hydraulic pressure in the forward signal line 42. This hydraulic pressure acts on the outer surface of the forward piston 48 at the same pressure as the pressure of the inching hydraulic line 32. At this time, since the hydraulic pressure receiving area at the outer surface of the forward piston 48 is always larger than the area of the inner surface of the forward piston 48, the forward piston 48 is directed toward the inside of the directional valve 38. Moments are moved and adhered momentarily. In this case, of course, the reverse piston 52 is in close contact with the outside simultaneously. Such close adhesion to the inside of the forward piston 48 is allowed only up to a predetermined limited range by the forward spool 52 so that pressure equal to the difference in the hydraulic pressure area of the forward piston 48 acts on the forward piston 48. As a result, the direction switching valve 38 is converted in the forward direction to supply and actuate the oil from the inching hydraulic line 32 to the forward clutch 56 through the forward hydraulic line 58 to perform the forward control. will be.

Conversely, when switching to the reverse direction, the electrical signal is input to the reverse solenoid valve 46 associated with the direction switching valve 38 to generate the hydraulic pressure in the reverse hydraulic line 46. This hydraulic pressure acts on the outer surface of the reverse piston 50 at the same pressure as the pressure of the inching hydraulic line 32. At this time, since the hydraulic pressure receiving area at the outer surface of the reverse piston 50 is always larger than the area of the inner surface of the reverse piston 50, the reverse piston 50 is directed toward the inside of the directional valve 38. Moments are moved and adhered momentarily. In this case, of course, the forward piston 48 is in close contact with the outside. Such close contact with the reverse piston 50 is allowed only to a predetermined limited range by the reverse spool 54 so that the pressure corresponding to the difference in the hydraulic pressure area of the reverse piston 50 acts on the reverse piston 50. Therefore, as a result, the direction switching valve 38 is switched in the reverse direction so that the oil pressure from the inching hydraulic line 32 is supplied to and acted on the reverse clutch 60 through the Junin hydraulic line 62 so that the reverse control can be performed. Will be.

For each of these forward and reverse movements, the hydraulic pressure required to actually turn the directional valve in a predetermined direction is controlled even at a relatively low pressure by the respective operations of the solenoid valve, the spool, the inching valve, and the like. The predetermined direction can be easily changed.

As a result, in the neutral state, the hydraulic pressure is formed in the inching hydraulic line and the inching clutch, and the braking function that actually restrains the forward and backward clutch is prevented, and the drag phenomenon of the forward and backward clutch is prevented. By the action of the reversing pistons and the respective spools associated with them, the shift to forward and reverse can be kept stable by utilizing the difference between the hydraulic pressure area and the hydraulic pressure formed on the outside of them.

As described above, according to the forward and backward control apparatus of the power transmission device according to the present invention, in the neutral state, it is possible to stably maintain the neutral, forward and backward positions regardless of the vibration and shaking of the operating lever, and in particular, in the neutral state Since the drag phenomenon of the clutch is prevented, the vehicle or the ship can be completely prevented from being abnormally rotated or driven, thereby improving driving performance.

While a preferred embodiment according to the present invention has been described above, it will be understood by those skilled in the art that various modifications and changes can be made without departing from the scope of the appended claims.

Claims (4)

A hydraulic pump 22 for sending pressure oil, a main line 24 for supplying pressure oil discharged by the hydraulic pump, and a main line 24 connected to the main line 24 to control the oil pressure and press the pedal pedal 28. To control switching between the inching valve 30 which is operated by the switching operation, the inching hydraulic line 32 connected to supply the hydraulic oil from the inching valve 30 to the inching clutch 36, and the hydraulic oil from the inching hydraulic line. In the forward and backward control device of the power transmission device including a direction switching valve 38 and a forward clutch 56 and a reverse clutch 60 to which pressure oil supplied from the direction switching valve is applied, respectively, On the inching hydraulic line 32 between the direction switching valve 38 and the inching valve 30, a forward and backward solenoid valve 39 for controlling the switching of the direction switching valve 38 in the left and right directions according to the forward and backward signals. In the forward and backward hydraulic lines (58, 62), which are supplied to the forward and backward clutches (56, 60) from the direction switching valve (38), a conjoined hydraulic line (66) is formed by the shuttle valve (64). A forward and backward control device for a power transmission device, characterized in that a cumulator (68) is provided. The forward piston (48) of claim 1, wherein the direction switching valve (38) is provided with an oil pressure generated in the forward signal line (42) applied to the outer side surface so as to be in close contact with the inside of the direction switching valve (38). In addition, the hydraulic pressure generated in the reverse signal line 46 is applied to the outer hydraulic pressure (受壓) surface is instantaneously in close contact with the inside of the directional valve 38, and the forward piston 48 It is built in the forward spool 52 and the backward piston 50 to limit the close movement to the inside and the hydraulic pressure acts on the forward piston by the difference in the pressure area of the outside thereof, the close movement inward And a reverse spool (54) for restricting and causing hydraulic pressure to act on the reverse piston by the difference in the hydraulic pressure area of the outside thereof. The inching valve of claim 1, wherein the inching valve is configured to generate hydraulic pressure in the inching hydraulic line 32 and the inching clutch 36 to prevent dragging of the forward clutch and the reverse clutch in a neutral state. The forward and backward control device of the power train, characterized in that. According to claim 1, wherein the forward and backward solenoid valve 39 is divided into a forward solenoid valve 40 and a reverse solenoid valve 44, the forward solenoid valve 40 through the forward signal line 42 A power transmission device, characterized in that connected to the forward pressure receiving portion of the directional valve 38, the reverse solenoid valve 44 is connected to the reverse pressure receiving portion of the directional valve 38 via the reverse signal line (44). Forward and backward control.