JPS5821101B2 - Transmission device for air-driven starters of internal combustion engines - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a transmission device for an air-driven starter for starting an internal combustion engine such as a gas turbine.

Generally, an internal combustion engine such as a gas turbine for power supply in a computer room is not allowed to stop on one side of the computer itself, so it is necessary to start the internal combustion engine quickly and reliably in the event of an emergency such as a power outage.

Therefore, in the starter for starting an internal combustion engine as described above, a transmission device is connected to an air motor that can obtain a large torque, and the rotational force of the air motor is transmitted to the internal combustion engine by the transmission device. .

Conventionally, such transmission devices are of the Bendex type, in which one end of the rotating shaft is connected to the drive shaft of the air motor, and a helical spline is bored at the other end of the rotary shaft, and a pinion is attached to the shaft in the axial direction. movably interlocked,
When the air motor is driven to rotate, the pinion moves along the helical spline due to inertia and meshes with the ring gear installed in the internal combustion engine to start the internal combustion engine.Afterwards, when the internal combustion engine starts, the pinion moves in reverse along the helical spline. A type that moves in the direction of the ring gear and disconnects from the ring gear is used.

In such a mechanism, the pinion rapidly pops out while rotating at high speed and engages with the ring gear, which can cause a large impact force to act on the pinion, damaging the teeth, or impacting the rotating shaft with torque, causing damage to the shaft. was there.

The present invention has been made in view of this point, and by appropriately controlling the amount of air supplied to the motor, which is linked to the starter rotary shaft so as to be able to move forward and backward in the axial direction Q, the starting rotary shaft is It is an object of the present invention to provide a transmission device for an air-driven starter of an internal combustion engine, which can be connected to the starting shaft of the internal combustion engine without any interference.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 1 denotes an air-start drive machine that starts an internal combustion engine such as a gas turbine for power supply in a computer room, and starts the internal combustion engine by moving a starting rotating shaft 2 with compressed air. An air motor 4 for driving the starting rotating shaft 2 is connected to the starting transmission device 3.

As shown in detail in FIG. 2, in the transmission device 3, a piston valve 6 is slidably inserted into a cylindrical casing 5 only in the axial direction, and further penetrates through the casing 5 and the piston valve 6. A starting rotating shaft 2 is rotatably supported.

A bearing 7.7 is interposed between the starting rotation shaft 2 and the piston valve 6, and is configured so that they can move forward and backward integrally only in the axial direction.

One end of the starting rotation shaft 2 is connected to the drive shaft 4a of the air motor 4 via a reduction gear (not shown), while an involute spline 8 is formed at the other end, and a portion of the involute spline 8 is connected to the internal combustion engine. It is disconnected from the starting shaft.

The interior of the casing 5 is divided by the piston valve 6 into a first air chamber 9a on the internal combustion engine side and a second air chamber 9b on the air motor side.

Inside the first air chamber 9a, there is a spring 10 that presses the piston valve 6 in the direction of disconnection (rightward in FIG. 2) in which the connection between the starting shaft of the internal combustion engine and the starting rotating shaft 2 is released. Shrinked.

A slight clearance 8a is provided between the casing 5 and the rear part of the involute spline 8 of the starting rotation shaft 2.

Therefore, when the clearance 8a is closed due to a slight movement of the starting rotating shaft 2, the inside of the first air chamber 9a becomes airtight, and the air inside is compressed by the movement of the starting rotating shaft 2, thereby causing the piston valve to open. 6 piston part 6a
It exhibits a cushion spring action so that it does not come into violent contact with the casing 5.

Further, an air hole 11 having one end opened to the second air chamber 9b and the other end opened to the outside air is opened in the casing 5 to form a piston means 12, and compressed air is supplied to the second air chamber 9b for connecting the starting rotation shaft 2. 2. When the air flows into the air chamber 9b, the piston valve 6 (starting rotation shaft 2) is moved in the connection direction (leftward in FIG. 2) where the starting rotation shaft 2 connects with the starting shaft of the internal combustion engine. It is configured.

Furthermore, the casing 5 has first and second exhaust holes 13 which have one end opened to the outside air and the other end opened into the casing 5.
a and 13b, respectively, and first and second recesses 14a are formed in the valve portion 6a of the piston valve 6 corresponding to the first and second exhaust holes 13a and 13b and the second air chamber 9b.
, 14b are provided to form the valve means 15.

The valve means 15 controls the amount of air supplied to the air motor 4, and the first fourth part 14a allows the second air chamber 9b and the first exhaust hole 13a to communicate with each other when the piston valve 6 moves slightly in the connection direction. , the second fourth part 14b is connected to the first exhaust hole 13 when the piston valve 6 further moves in the connecting direction.
a is closed and the starting rotating shaft 2 moves to a state where the involute spline 8 is almost completely engaged with the starting shaft of the internal combustion engine, the second air chamber 9b and the second exhaust hole 1 are closed.
3b.

Air control means 16 are associated with said piston means 12 and valve means 15.

The air control means 16 is configured to rotate the air motor 4 at a low speed at the beginning of the connection operation of the starting rotation shaft 2.

That is, the air source 17 is branched into a transmission device air supply path 21 and an air motor air supply path 22 via a filter 18 , a regulator 19 and a lubricator 20 , respectively, and the transmission device air supply path 21 is connected to a transmission device via an electromagnetic switching valve 23 . It is connected to the air hole 11 of the device 3, and the electromagnetic switching valve 23 is connected to the discharge part 23a.
It is formed in a 3-point, 2-position type having a supply section 23b and a solenoid 24 on the side.

The air motor air supply path 22 is connected to the air motor 4 via a switching valve 25, and the switching valve 25 connects the stop section 25a and the supply section 2.
5b, a spring 26 is provided on the side, and its pilot line 25c is connected to the second exhaust hole 13b of the transmission device 3 via a check valve 27. When pressure is applied,
It is configured to switch to the supply section 25b.

Further, the first exhaust hole 13a of the transmission device 3 is connected to the air motor air supply path 22 via the check valve 28, and the initial air supply path 29 is connected to the air motor air supply path 22.
is formed, and the initial stage of driving the air motor 4 (initial stage of connection operation)
Compressed air is supplied from the upper distribution air passage 29 to rotate at a low speed.

The transmission air supply path 21 is also connected to a pilot line 25c of the switching valve 25 via a check valve 30.

A power source 31, an operation switch 32, and a pressure switch 33 are sequentially connected and wired to the solenoid 24 of the electromagnetic switching valve 23, and the pressure switch 33 is turned off when the exhaust gas pressure reaches a set value after the internal combustion engine has started. It is.

In addition, 34 is a rotation pin that restricts the rotation of the piston valve 6, 35 is a main shaft, 36 is a key, and 37 is a connecting fitting.

Next, the operation of the above device will be explained. When the operation switch 32 is turned on to start the internal combustion engine, the lunoid 24 is activated, the electromagnetic switching valve 23 is switched to the supply section 23b, and compressed air is supplied from the air source 17. is the second of transmission 3
The air is supplied to the air chamber 9b.

When compressed air is supplied to the second air chamber 9b, the piston valve 6 (starting rotation shaft 2) begins to move in the connection direction, and the second
The air chamber 9b and the first exhaust hole 13a communicate slightly through the first recess 14a, and compressed air begins to leak and is supplied to the air motor 4 through the supply path 29.

Subsequently, when the piston valve 6 moves and the second air chamber 9b and the first exhaust hole 13a are completely communicated with each other and a large amount of ventilation begins, the air motor 4 begins to rotate at a low speed.

Meanwhile, the starting rotating shaft 2 continues to move in the connection direction, and as the air motor 4 rotates at a low speed, the starting rotating shaft 2 also rotates at a low speed, and a little later than the low speed rotation, the tip of the starting rotating shaft 2 is connected to the internal combustion engine. The tip of the involute spline 8 rotates and engages with the starting shaft of the involute spline 8.

When the tips of the involute splines 8 engage, the first exhaust hole 13a is closed and the air motor 4 temporarily stops rotating.

The starting rotary shaft 2 continues to move without rotating, and when the involute spline 8 is almost completely engaged, the second
The air chamber 9b and the second exhaust hole 13b begin to communicate slightly through the second recess 14b, and pressure begins to be applied to the switching valve 254 through the pilot line 25c.

When the piston valve 6 moves further and the starting rotation shaft 2 is completely engaged with the starting shaft of the internal combustion engine, and the second air chamber 9b and the second exhaust hole 13b are completely connected, the pilot line 25C Pressure is applied through the switching valve 25 and the switching valve 25 is switched to the supply section 25b.

As a result, compressed air is supplied to the air motor 4 from the air supply path 22, causing it to rotate at high speed, and accordingly, the starting rotation shaft 2 also rotates at high speed to start the internal combustion engine.

When the internal combustion engine starts and the exhaust gas pressure reaches the set value, the pressure switch 33 turns OFF, the solenoid 24 stops, the electromagnetic switching valve 23 switches to the discharge part 23a, and the second
The compressed air in the air chamber 9b is discharged and the piston valve 6
is moved in the disconnection direction by the spring 10, and accordingly, the starting rotation shaft 2 is also moved in the disconnection direction, and the connection with the internal combustion engine is severed.

In addition, due to the discharge of compressed air from the second air chamber 9b, the switching valve 25
is switched to the stop portion 25a, and the rotational drive of the air motor 4 is stopped.

With the above configuration, according to the present invention, the starting rotating shaft can be connected to the internal combustion engine by moving it while rotating at a low speed, and after once stopping rotation and being completely connected, it can be rotated at a high speed. Since the connection with the internal combustion engine can be made extremely gently and reliably, and no impact force is applied to the starting rotation shaft, it can be made smaller without requiring strength, and the entire device can be made compact and lightweight. G) It has excellent practical effects.

[Brief explanation of drawings]

The drawings illustrate an embodiment of the invention, in which FIG. 1 is a schematic diagram of an air-driven starter and FIG. 2 is a longitudinal sectional view of the transmission. DESCRIPTION OF SYMBOLS 1...Air drive starter, 2...Starting rotation shaft, 3...Transmission device, 4...Air motor, 4a...Drive Shaft, 5...Casing, 6...Piston valve, 7...
Bearing, 9a...First air chamber, 9b...
...Second air chamber, 10...Spring, 11
...Air hole, 12...Piston means,
13a...first exhaust hole, 13b...second exhaust hole, 14a...first recess, 14b...
...Second recess, 15...Valve means, 16.
... Air control means, 23 ... Solenoid switching valve, 25 ... Switching valve.

Claims (1)

[Claims] 1 A transmission device for starting an internal combustion engine such as a gas turbine by an air motor, in which one end of the starting rotating shaft, which is connected to the starting shaft of the internal combustion engine at the time of starting, is rotatably supported in the casing via a bearing. The other end of the starting rotating shaft is connected to the air motor so that it can move forward and backward in the axial direction, and the inside of the casing is inserted into the casing so that it can move. , divided into a first air chamber and a second air chamber,
The first air chamber is fitted with a spring that presses and biases the piston valve in a direction in which the connection between the starting shaft and the starting rotation shaft of the internal combustion engine is released, while the second air chamber is equipped with The structure is configured such that compressed air flows in to move the piston valve in the direction of connecting the starting shaft and the starting rotating shaft of the internal combustion engine, and the piston valve is provided with first and second exhaust holes respectively in the casing. The valve means is configured by forming first and second recesses corresponding to the first and second exhaust holes and the second air chamber, and connecting the second air chamber and the first exhaust hole through the first recess. The second air chamber does not communicate with either the first or second exhaust hole between the initial stage of the connecting operation and the final stage of the connecting operation in which the second air chamber and the second exhaust hole are communicated through the second recess. A transmission device for an air-driven starter of an internal combustion engine, characterized in that there is a middle period of connection operation.