JPH0585390B2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Object of the Invention [Field of Industrial Application] This invention relates to a braking device for a hoisting machine that hoists cables of a cableway.

[Prior Art] Cableways are important as a means of transportation in mountainous areas, and they are an endless cableway with carriers such as gondolas and chairs suspended at regular intervals, and are connected between a lower terminal at the foot of a mountain and a lower terminal at the top of a mountain. Passengers such as skiers and mountain climbers, as well as cargo, are transported by circulation in a fixed direction around two pulleys located at the upper terminal of the train.

At least one of the two pulleys is a drive pulley and is rotationally driven by a drive device, and the regular or emergency braking device is configured to control the rotation of this drive pulley.

On a cableway, stopping with a sudden shock is dangerous because it causes the carrier to sag, and especially on a chair lift, there is a risk of passengers or objects falling, so even if the drive device is stopped, it is dangerous.
Note that sudden stopping methods cannot be used to brake a pulley that continues to rotate due to inertia.

However, since quick response is the most important requirement for cableway safety, a braking system that is quick to respond and has no shock is required. Conventionally, this type of braking involves pressing brake discs, which are braking members fixed to the upper and lower surfaces of the drive pulley that is hoisting up the cable, from above and below with brake shoes, and using frictional force to gradually move the drive pulley. A method has been adopted to stop it.

Conventionally, methods for pressing this shoe against the brake disc include a spring type, a weight type, an active tightening type, and others.

In addition, when the cableway is stopped, the shoe of this braking device is in a state of pushing the pulley and the brake is applied, so when operating the cableway, the shoe must be released from the brake disk of the pulley. This method of releasing the braking device cannot be separated when considering the braking device, and conventionally a pusher, magnet, hydraulic device, etc. have been used. .

Conventional braking devices tend to cause sudden shocks, and those that do not cause sudden shocks either take a long time to stop and lack quick response, or the braking devices are slow to release, resulting in an unreasonable load on the pulley drive device. However, there are problems such as high pressure, and a fully satisfactory braking device has not yet been obtained.

[Problems to be Solved by the Invention] This invention has been made in view of the above-mentioned circumstances. Therefore, it is an object of the present invention to provide a braking device for a hoisting machine that can quickly perform braking without a shock and also has excellent quick response in opening the braking device.

(B) Structure of the Invention [Means for Solving the Problem] In response to this object, the braking device for a hoisting machine of the present invention includes a brake that controls and releases the brake member by approaching and separating it from the brake member of the pulley. a pressing device that presses the brake shoe in the braking direction; and a pressure oil supply having a hydraulic pressure higher than the operating pressure of the sequence valve to open the brake shoe against the pressing force of the pressing device. A braking device comprising a hydraulic cylinder device that can be driven in a direction, and a hydraulic circuit that controls the hydraulic cylinder device, the hydraulic circuit being connected from a tank to the hydraulic cylinder via a pump and a first switching valve. The first switching valve further includes a main circuit connected to a hydraulic pressure release circuit and a hydraulic pressure accumulating circuit, and is configured to intermittent oil flow from the pump in synchronization with braking/release operations of a braking device, The discharge circuit reaches the main circuit from the tank via a parallel circuit of a second switching valve and throttle valve and a first sequence valve, and the hydraulic pressure accumulator circuit connects an accumulator to a second sequence valve and a check valve. The first switching valve and the second switching valve are configured to open and close in opposite phases, and the first sequence valve and the second switching valve The sequence valve is characterized in that it is configured to open when the hydraulic pressure is equal to or higher than the operating pressure.

Hereinafter, details of the present invention will be explained with reference to the drawings showing one embodiment.

In FIG. 1, 1 is a braking device.

The braking device 1 includes a brake shoe 7 for pressing brake discs 6a and 6b, which are brake members fixed to the peripheral edges of the upper and lower surfaces of the drive pulley 5 hoisting the cable 4, from above and below, respectively.
a, 7b. That is, the tip inner surface 9a of the arm 8a of the braking device 1 is located parallel to and opposite to the upper surface of the brake disc 6a, and the shoe 7a is attached to the tip inner surface 9a. The tip inner surface 9b of the other arm 8b of the braking device 1 is located parallel to and opposite to the other arm 8b, and the shoe 7b is attached to this tip inner surface 9b. Therefore, the two arms 8a, 8
b are positioned so that their tips face each other and sandwich the peripheral edge of the pulley 5 from above and below.

The shoes 7a, 7b are shaped so as to be in flat contact with the upper and lower surfaces of the brake discs 6a, 6b, respectively.

The rear parts of the arms 8a and 8b are bent and intersect with each other on the side of the drive pulley 5, and after being pivotally connected to the fixed shaft 11 in a fixed position at the intersection part, the upper and lower positions are exchanged with each other, and the arms are bent again. Then, the rear end 12
a and 12b are located substantially parallel to each other and opposite to each other. The rear end portions 12a, 12b each have holes 13a, 13b penetrating vertically, and the holes 13a, 13
One round bar 14 is fitted into b. The round bar 14 is located parallel to the rotation center axis 10 of the drive pulley, and has rear end portions 12a, 12b in the holes 13a, 13b.
The rear end portion 12 is slidable with the opposing rear end portion 12.
They extend above and below b and 12a, respectively, and coil springs 15b and 15a are fitted into these portions, respectively. The coil springs 15b and 15a each have a nut 16b, a rear end portion 12b, and a nut 16b.
and the rear end portion 12a, and the tips of the arms 8a and 8b are configured to be able to press the brake shoes 7a and 7b against the brake discs 6a and 6b, respectively, by the elastic force of this coil spring. , arms 8a, 8b, fixed shaft 11, round bar 1
4. Coil springs 15a, 15b and nut 16
a and 16b constitute a pressing device 2 that presses the brake shoes 7a and 7b from above and below the drive pulley 5, that is, in the braking direction.

A cylinder 17 is arranged perpendicularly to the rotating shaft 10 of the drive pulley 5 between the inner surfaces 9a and 9b of the tip end of the arm, and both ends of the cylinder 17 are fixed to the inner surfaces 9a and 9b of the tip end, respectively.

The cylinder 17 is connected to the hydraulic circuit 3, and only when pressure oil with a pressure of 35 kgf/cm ² or more is supplied from the hydraulic circuit 3, the cylinder 17 resists the pressing force of the pressing device 2 to maintain the vertical distance between the arms 8a and 8b. Expand the brake shoes 7a, 7b to the brake disc 6.
It is designed so that it can be separated from a and 6b.

Next, the hydraulic circuit 3 will be explained.

As shown in FIG. 2, the hydraulic circuit 3 includes a tank 21
The main circuit 24 is connected to the hydraulic cylinder 17 via a pump 22 and a first switching valve 23.

The main circuit 24 reaches the pump 22 from the tank 21 via a branch point A. Pump 22 is coupling ring 2
It is driven by a motor 26 connected through 5, and is turned off when a brake operation switch (not shown) is turned on, and turned on when the brake operation switch is turned off. The main circuit 24 passing through the motor branches off into a pipe to a pressure vessel 28 after passing through a check valve 27 and reaches a branch point B to a pressure switch 31 . pressure switch 31
When the oil pressure rises to 140Kgf/ ^cm2 , pump 2
2 is turned off, and the pump 22 is set to be turned on when the oil pressure drops to 110Kgf/ ^cm2 .

The main circuit 24 passing through the branch point B is connected to the first switching valve 2
Reach 3. The first switching valve 23 is a solenoid valve, and is configured to cut off and cut off the oil from the pump 22 in synchronization with the braking/releasing operation, that is, to control the braking operation switch.
When it is turned on, the oil from the pump 22 is closed without flowing, and when the brake operation switch is turned off (the opening operation switch is turned on), it is opened.
The main circuit 24 passing through the first solenoid valve 23 is connected to the check valve 32
After passing through the branch pipe 33, the pipe branches off to the branch point C.

The branch pipe 33 is connected to a pressure gauge 35 via a gauge valve 34.
Connect to. The main circuit 24 branches off from a hydraulic pressure release circuit 36 (to be described later) at a branch point C, passes through a branch point D, reaches a branch point E, and here reaches a hydraulic cylinder 17 after branching from a hydraulic pressure accumulation circuit 37 (to be described later).

The hydraulic pressure release circuit 36 originates from the branch point C and includes a parallel circuit of a throttle valve 38 and a first sequence valve 41;
and reaches the tank 21 via the second switching valve 42. The throttle valve 38 is a valve that can variably adjust the flow rate of oil, and makes the flow rate smaller than that of the front and rear pipes. The first sequence valve 41 has a large-diameter passage, and the oil pressure from the branch point C is the operating pressure (in this embodiment,
It is set so that it is open when the pressure is higher than 35Kgf/cm ² ) and closed when it is lower than the operating pressure. The second switching valve 42 is a solenoid valve, and is configured to open and close the hydraulic pressure from the branch point C side in synchronization with the opening and braking operations of the brake device 1, that is, when the brake operation switch is turned off. Brake operation switch
When turned ON, it is closed so that oil does not flow from the branch point C side, and the open/close state is in the opposite phase with respect to the braking/release operation from the first switching valve.

The hydraulic pressure accumulation circuit 37 reaches a branch point E of the main circuit 24 from the accumulator 43 through a parallel circuit of a second sequence valve 44 and a check valve 45. The accumulator 43 is for example 210Kgf/ ^cm2 , and the second sequence valve 44 has the same configuration as the first sequence valve, but has a large diameter, and the oil pressure from the branch point E is the operating pressure (in this example, It is set so that it opens when the pressure is higher than 35Kgf/cm ² ) and closes when it is lower than the operating pressure.

In addition, there is a bypass 46 that reaches from the branch point A to the branch point B, and the bypass 46 passes from the branch point A to the manual pump 47, the branch pipe 51, and the check valve 52 that only allows flow from the branch point B. Reach point B. The branch pipe 51 connects the relief valve 48 to the tank 21.
reach.

Further, a branch pipe 53 from branch point C reaches the tank 21 from a stop valve 54, and another branch pipe 55 from branch point D reaches the tank 21 from a relief valve 56.

The relief valves 51 and 56 are set to, for example, 200 kgf/cm ² .

[Operation] In the braking device for the hoisting machine configured as described above, the operation of opening the braking device and starting the cableway will be described first.

When the brake switch is turned off (the drive switch is turned on), the drive device for the drive pulley 5 is turned on, the motor 26 is turned on, and the pump 22 is rotated.
At the same time, the first switching valve 23 opens and the second switching valve 42 opens.
is closed. Also, since the oil pressure at startup is 0,
First sequence valve 41, second sequence valve 4
4. Relief valves 48 and 46 are all closed. Therefore, the oil sucked up from the oil tank 21 by the pump 22 passes through the main circuit 24 to the cylinder 17.
flows to

Furthermore, when the pump sucks up oil and the hydraulic pressure inside the cylinder 17 becomes greater than 35 kgf/cm ² , the cylinder 17 resists the pressing force of the pressing device 2 and the arm 8
Increase the vertical distance between a and 8b, and brake shoe 7
a, 7b from the brake discs 6a, 6b. This releases the brake system and the cableway begins to circulate.

The first sequence valve 41 also opens when the oil pressure exceeds 35 Kgf/cm ² , and the pressure oil passes through the first sequence valve 41 , but the second switching valve 42 is closed, and the pressure oil passes through the second switching valve 42 . It will not be discharged from the tank 21.

On the other hand, since the second sequence valve 45 is also turned on at 35 Kgf/cm ² or more, the pressure oil passes through the second sequence valve 44 and flows to the accumulator 43, where the pressure is accumulated. Therefore, the pressure of the oil from the pump 21 is accumulated after the brake is opened, and the brake can be opened quickly.

When the oil pressure reaches 140Kgf/ ^cm2 , pressure switch 3
1 turns off the pump 22, so the motor 26
stops and remains in that state, and the cord continues to circulate.

Next, during operation, the oil pressure is 140 to 110Kgf/cm ²
It is to be maintained. In other words, when the oil in the hydraulic circuit 3 leaks and the oil pressure drops to 110Kgf/ ^cm2 ,
The pressure switch 31 is turned ON, the pump 22 is activated, and the oil pressure rises again. When it reaches 140Kgf/cm ² , the pressure switch is turned OFF and the pump stops. This process is repeated, and the oil pressure increases from 140 to 110Kgf/cm2.
cm ² and the relief valves 48, 56 are closed.

Next, we will discuss the effect during braking. When the brake operation switch is turned ON, the motor 26 of the pump 22 is stopped, and at the same time the first switching valve 23 is closed and the second switching valve 42 is opened, so the pressure is 140 Kgf/cm ² or less.
The oil in the hydraulic cylinder 17, which was 110Kgf/cm ² , is
The oil flows out into the tank 21 through the first sequence valve 41 which is open, the throttle valve 38, and the second switching valve 42, and the oil stored in the accumulator 43 is also opened. Similarly, it flows out into the tank 21 through the valve 44 and the check valve 45.

Here, since the first sequence valve 41 and the second sequence valve 44 have large diameters,
The oil pressure in the hydraulic cylinder 17 and the accumulator 43 drops to 35Kgf/cm ² .

When the oil pressure in the hydraulic cylinder 17 reaches 35Kgf/ ^cm2 , the brake discs 6a, 6b and the shoes 7a, 7
The distance δ between b becomes zero, and braking is started.

At the same time, the first sequence valve 41 is closed,
The oil flows through a throttle valve 38 whose diameter is narrowed to pre-adjust the flow rate, and a second switching valve 4 which is in an open state.
2 and then flows out into the tank.

The second sequence valve 44 is also closed, but the pressure oil stored in the accumulator at 35 kgf/cm ² flows out through the check valve 45 and flows into the main circuit from the branch point E.
4 and similarly flows out into the tank 21 through the throttle valve 38 and the second switching valve 42 which is in the open state. Due to the oil pressure accumulated in the accumulator 43, the rate of decrease in the oil pressure in the hydraulic cylinder 17 is reduced,
It gradually decreases from 35Kgf/cm ² to 0Kgf/cm ² .
This is an important point.

That is, the drive pulleys 5 of the brake shoes 7a, 7b
The braking force T for is given by T=P-f(p)...(1), where P: the pushing force of the pushing device (constant), f(p): the return force due to the hydraulic pressure P in the hydraulic cylinder, and Therefore, an increase or decrease in f(p) corresponds to an increase or decrease in p. Since this braking device is designed so that T=0 when p=35, that is, f(35)=P, T in equation (1) is defined for the case p≦35. ing.

Now, as mentioned above, the hydraulic pressure p in the hydraulic cylinder 17
gradually decreases from 35Kgf/cm ² , so f(p)
T gradually decreases, and accordingly T gradually increases, as shown in curves 57 and 58 in Fig. 3, where the slow braking continues, and finally, with sufficient braking force, the braking becomes reliable. Then, the pulley is stopped and the braking device 1 performs gentle braking without shock.

In this way, in this invention, the braking device operates in two stages, and in the first stage, the hydraulic pressure in the cylinder is increased.
After the pressure drops rapidly to 35Kgf/cm ² in an extremely short period of time and the operating time is shortened, in the second stage, slow braking is performed over a sufficient period of time, including the time shortened in the first stage. As a result, shock-free braking is achieved. By adjusting the flow rate of the throttle valve 38, the braking time can be shortened from _t1 to _t4 by curves 57a and 5.
8a and curves 57b and 5 where the braking time is long from t ₁ to t ₅ .
8b can be selected.

(c) Effects of the Invention As is clear from the above explanation, according to the present invention, the operation is quick, the gentle braking necessary for stopping is sustained, and the braking force after stopping is excellent. It is possible to perform braking without accompanying.
Furthermore, it is possible to obtain a braking device for a hoisting machine that is excellent in quick response when the braking device is released.

[Brief explanation of the drawing]

FIG. 1 is an explanatory side view showing a braking device for a hoisting machine according to the present invention, FIG. 2 is a hydraulic circuit diagram, and FIG. 3 is a graph showing changes over time in hydraulic pressure in a hydraulic cylinder and braking force. 1... Braking device, 2... Pressing device, 3... Hydraulic circuit, 4... Cable, 5... Drive pulley, 6a, 6b
...Brake disc, 7a, 7b...Brake shoe, 8a, 8b...Arm, 9a, 9b...
Inner surface of the tip, 10... Rotating shaft, 11... Fixed shaft,
12a, 12b... rear end portion, 13a, 13b...
Hole, 14...Round bar, 15a, 15b...Coil spring, 16a, 16b...Nut, 17...Hydraulic cylinder, 21...Tank, 22...Pump, 23
...First switching valve, 24...Main circuit, 25...Coupling, 26...Motor, 27...Check valve, 28...Pressure vessel, 31...Pressure switch,
32... Check valve, 33... Branch pipe, 34... Gauge valve, 35... Pressure gauge, 36... Hydraulic pressure release circuit,
37... Hydraulic pressure accumulation circuit, 38... Throttle valve, 41...
...first sequence valve, 42...second switching valve,
43... Accumulator, 44... Second sequence valve, 45... Check valve, 46... Bypass, 4
7...Manual pump, 48...Relief valve, 51...
... Branch pipe, 52 ... Check valve, 53 ... Branch pipe, 5
4...stop valve, 55...branch pipe, 56...relief valve, 57...curve, 58...curve.

Claims (1)

[Claims] 1. A brake shoe that approaches and separates from a brake member of a pulley to brake and release the brake member, and a pressing device that presses the brake shoe in a braking direction;
A hydraulic cylinder device capable of driving the brake shoe in the opening direction against the pressing force of the pressing device by receiving pressure oil having a hydraulic pressure higher than the operating pressure of the sequence valve, and controlling the hydraulic cylinder device. A braking device having a hydraulic circuit, the hydraulic circuit comprising a main circuit connected from a tank to the hydraulic cylinder via a pump and a first switching valve, and connected to a hydraulic pressure release circuit and a hydraulic pressure accumulation circuit. The first switching valve is configured to intermittent oil flow from the pump in synchronization with braking/release operations of the braking device, and the hydraulic pressure release circuit is connected to the second switching valve and the throttle valve from the tank in a first sequence. The hydraulic pressure accumulator circuit is connected to the main circuit through a parallel circuit with a valve, and the hydraulic pressure accumulator circuit is connected from an accumulator to the main circuit through a parallel circuit with a second sequence valve and a check valve. The switching valve and the second switching valve are configured to open and close in opposite phases, and the first sequence valve and the second sequence valve are configured to open when the hydraulic pressure is equal to or higher than the operating pressure. A braking device for a winding machine characterized by the following.