JPH0127264B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control device for an air motor, and more particularly to a control device for an air motor for starting an internal combustion engine, particularly a small gas turbine.

Traditionally, starting devices for internal combustion engines include systems in which a pinion rotates at high speed and meshes with the engine's ring gear during startup, and after the engine starts, the pinion retreats and disengages from the ring gear. There was a system in which a high-speed rotating shaft with a spline cut into it was inserted into the end of the rotating shaft, and the tip of the spline retreated after the engine was started, but in any case, unless special measures were taken, the starting device could not be used. Large impact damage often occurs when meshing with internal combustion engines. Therefore, in an internal combustion engine starting device using an electrically driven starter motor, the rotation speed of the device's pinion is set in advance by meshing with the ring gear while rotating at a low speed, and then starting at a high speed based on a sensor. , which avoids impact damage and this method is widely known.

However, this electric starting device requires a battery, charging pressure regulator, etc. In particular, in large internal combustion engines that are directly connected to emergency work equipment, a small internal combustion engine for auxiliary equipment is attached, and this is connected to the electric starting device. Even when I tried to start the engine, the electric starter would not turn on in an emergency, which was inconvenient.

On the other hand, in an internal combustion engine starting device that uses an air motor, in order to prevent shock damage, the device rotates at a low speed when the pinion and ring gear are engaged, and once they are engaged, the device stops and then rotates at high speed to start the engine. However, in this proposal, when the pinion and ring gear mesh, the pinion is pushed out only by the piston, so even if the pinion is engaged at low speed, the characteristics of the air motor will still be affected. It was rotating at a considerable speed, and there was a risk of damage.

Therefore, the present invention is a starting device for an internal combustion engine using an air motor, and the starting device is controlled by the compressed air itself while paying attention to sudden motion characteristics due to air drive. To provide a highly reliable starting device for an internal combustion engine, which avoids impact damage that occurs at the moment of engagement, and prevents the starting device from re-engaging even after the engine is started.

Hereinafter, the structure of the present invention will be described in detail based on embodiments shown in the accompanying drawings. FIG. 1 is an overall schematic diagram, FIG. 2 is a sectional view of the air motor with the air control valve omitted, and FIG. 3 is an enlarged sectional view of the air control valve.

[Summary of configuration]

In FIG. 1, 1 is an air tank that stores air compressed by a compressor (not shown);
3 is a gate valve, 3 is a filter that removes foreign matter from the compressed air, 4 is an oiler for mixing lubricating oil to supply lubricating oil to the air motor, 5 is an air control valve, 6 is the air motor body, 7 is a silencer, 8 is a pinion ,
9 is a ring gear of the internal combustion engine that meshes with the pinion;
Reference numeral 10 denotes a start valve, which communicates with the air motor main body 6 through supply/discharge control tubes 10', 10'.

The outline of the operation of this device is as follows:
By manually pressing , the air control valve 5 is actuated, the air motor is started, and the pinion 8 is jumped out, that is, moved forward to mesh with the ring gear 9 and start the internal combustion engine.

[Configuration of air valve and air motor]

In this embodiment, the air valve 5 and the air motor have the following configuration.

In FIG. 2, the air motor is a vane type motor, and a rotor 12 which is eccentric with respect to the cylinder 11 is housed in a cylinder 11. Ball bearings 17 to 15 and 16
and is rotatably supported via roller bearings 18. A plurality of blades 19 are provided on the rotor 12 so as to be slidable radially with respect to the center of the rotor 12, and the outer ends of these blades 19 are always housed within the cylinder 11. The cylinder 11
is provided with a plurality of air inflow passage grooves 20 on the inlet side and a plurality of air outflow passage grooves 21 on the outlet side, the inlet side communicates with the oiler 4 side explained in FIG. 1, and the outlet side communicates with the silencer 7. ing. Their mechanisms are well known. (Japanese Patent Application Laid-Open No. 57-91375).

Next, regarding the speed reduction mechanism connected to the air motor, a pinion 23 is carved into the extending end of the rotor shaft 14, and the pinion 23 is connected to the internal gear 22.
The rotation of the rotor 12 is reduced by the internal gear 22, and a drive shaft 30, which will be described later, is rotated. The internal gear 2
2 is integrally extended with a cylindrical body 24 having a smaller diameter than the cylindrical body 24 to serve as a transmission shaft, and these internal gears 22 and the cylindrical body 24
are ball bearing 25 and roller bearing 2
It is supported by 6. The ball bearing 25 is supported by the side housing 16, the roller bearing 26 is supported by the intermediate cylinder 28, and the base of the intermediate cylinder 28 is supported by the casing 2.
7 is fitted. A threaded spline 29 is carved on the inner circumference of the cylindrical body 24 in the front, and the threaded spline 2
9 meshes with a threaded spline formed on the drive shaft 30. This threaded spline 29 functions to move the shaft forward when the rotation of the driven side is stopped. A stopper 31 is fixed to the end of the drive shaft 30 on the threaded spline 29 side, and the pinion 8 explained in FIG. 1 is fixed to the other end. A roller bearing 32 that also receives thrust is provided between the pinion 8 and the threaded spline 29, and the drive shaft 30 is supported by the roller bearing 32 and the stopper 31. Further, in the ring-shaped space formed by the intermediate cylinder 28 and the casing 27, a piston 33 is slidably provided, and the roller bearing 32 is mounted inside the extension portion 34 of the piston 33. As the piston 33 slides, the drive shaft 30 moves forward together with the roller bearing 32.

A working chamber 35 is provided on the head side of the piston 33.
A communication port 36 is provided on each skirt side, and the piston 33 is always urged toward the working chamber 35 by a spring 38.

[Air control valve configuration]

Next, regarding the air control valve 5, in FIG.
A main valve main body 39 is mounted and fixed on the inlet side of the main valve body 39, and an air control valve 5 is attached to the main valve main body 39.

The main valve body 39 is approximately a valve 40 and a valve spring 4.
1 and a valve stem 42, the valve stem 42 is guided vertically by an intermediate frame 43 of the valve body 39 and slides thereon. A piston 44 is fixed to the upper end of the valve stem 42, and the back of the piston 44 and the intermediate frame 4
3 forms a working chamber 45. 39' indicates an opening communicating with the oiler 4 side.

The air control valve 5 is roughly the upper spool valve 4.
7. Consisting of a lower conical valve 48, a barrel 49, and a valve seat 50, the protruding rod 52 of the lower conical valve 48 is fitted into the central hole 51 of the upper spool valve 47, and are coupled so that they can be joined and separated. Slide up and down inside. Upper spool valve 47 and lower conical valve 4
Both valve springs 8 have compression-biased valve springs 53 and 54 and are biased upward.

Regarding the port of the air control valve 5,
The first port 55 communicates with the control tube 10' described in FIG. 1, and the control tube 10' communicates with the air tank 1 via the start valve 10. The first port 55 is connected to the conical valve chamber 5 in which the lower conical valve 48 is built.
It is temporarily set up on 6th. The second port 57 communicates with the working chamber 35 described in FIG. 2 and is provided adjacent to the conical valve chamber 56. The third port 58 has a narrow pore and communicates with the second port 57, and is provided on the inlet side of the cylinder 11. The fourth port 59 communicates with the working chamber 45 and is provided in an outer peripheral notch 60 of the barrel 49 . The outer peripheral notch 60 communicates with the center hole 61 of the protruding rod 52 and also communicates with the conical valve chamber 56 via an on-off valve consisting of a small land 62 of the barrel 49 and an O-ring 63 of the upper spool valve 47. The fifth port 64 communicates with the communication port 36 described in FIG. 2 and is provided adjacent to the upper spool valve chamber 65.

[Operation at the start of meshing between pinion and ring gear]

Since the configuration of this embodiment is as described above, the following operations are performed.

First, when the start valve 10 is opened, compressed air is introduced from the air tank 1 into the first port 55, and the compressed air is discharged from between the lower conical valve 48 lifted by the valve spring 54 and the valve seat 50. The water is divided into a second port 57 and a third port 58 and flows out. The compressed air flowing out from the second port 57 is introduced into the working chamber 35 shown in FIG. 2, and causes the piston 33 to slide in the direction in which the pieon 8 pops out. On the other hand, the compressed air that is throttled and flows out from the third port 58 is introduced into the cylinder 11 and rotates the rotor 12 at a low speed. As a result, code 23→
22→24, the drive shaft 30 rotates via the threaded spline 29, and the drive shaft 30 attempts to be pulled out via the roller bearing 32 by the sliding movement of the piston 33 in the protruding direction, that is, in the forward direction. However, since the threaded spline 29 is threaded so that it moves forward when the rotating drive shaft 30 is stopped, if the piston 33 attempts to move the drive shaft 30 forward, the drive shaft 30 will instead be reversed. As a result, the pinion 8 rotates more slowly and engages with the ring gear 9 slightly. Once the pinion 8 and ring gear 9 begin to engage, this time,
The rotation preventing force of the ring gear 9 on the drive shaft 30 acts on the threaded spline 29, and the piston 33
The drive shaft 30 moves forward quickly, that is, the piston fits into the pinion 8 and the ring gear 9 completely mesh with each other. This position is a position where the stopper 31 of the drive shaft 30 comes into contact with the stepped portion 66 of the cylinder body 24, so that the drive shaft 30
The forward movement of is stopped. Moreover, the same position is piston 33
This is also the position where the working chamber 35 and communication port 36 communicate with each other, and compressed air is introduced from the communication port 36 into the upper spool valve chamber 65.

[Opening operation of the main valve body]

As described above, the movement of the piston 33 brings the working chamber 35 into communication with the communication port 36, and compressed air is introduced into the upper spool valve chamber 65 from the fifth port 64, pushes the upper spool valve 47 downward, and causes the lower conical While seating the valve 48 on the valve seat 50,
The small land 62 of the barrel 49 and the O-ring 63 of the upper spool valve 47, which had been closed until now, are now opened.
The conical valve chamber 56 and the outer peripheral notch 60 communicate with each other. Therefore, compressed air enters the working chamber 4 from the fourth port 59.
5, pushing up the piston 44 and opening the valve 40 of the main valve. As a result, air tank 1
A large amount of compressed air is introduced into the cylinder 11 and rotates the rotor 12 at high speed. At this time, since the lower conical valve 48 is seated on the valve seat 50, compressed air is introduced from the third port 58 in the opposite manner to the previous one, and is introduced into the working chamber 35 via the second port 57. and continues to push the piston 33.

[Closing operation of the main valve body]

The internal combustion engine starts with the high-speed rotation of the rotor 12, but when the internal combustion engine starts, the ring gear 9 rotates faster than the pinion 8, and a force acts to rotate the drive shaft 30 faster, so the spline 29 As a result, the drive shaft 30 moves backward, and the pinion 8 and ring gear 9 disengage.
As the drive shaft 30 retreats, the piston 33 also retreats against the compressed air in the working chamber 35, and the communication port 36
Close. Therefore, the compressed air introduced into the upper spool valve chamber 65 is gradually discharged through a labyrinth formed on the outer periphery of the piston 33, and the pressure is reduced. As a result, the upper spool valve 47 is pushed up by the pressure in the conical valve chamber 65, the small land 62 and the O-ring 63 are closed again, and the outer peripheral notch 60 and the conical valve chamber 56 are no longer in communication. Therefore, compressed air drips into the working chamber 45, while
Since the upper spool valve 47 is retracted, the air in the working chamber 45 is released to the atmosphere through the center hole 61 and the port 67, while the valve spring 41 closes the valve 40 and stops the rotation of the rotor 12. .

At this time, compressed air continues to be supplied to the first port 55, so the conical valve chamber 56 is pressurized, the lower conical valve 48 remains seated against the valve spring 54, and the start is started. Even if the valve 10 is not closed, the pinion 8 will not pop out again inadvertently and is locked, so to speak.

When the start valve 10 is then closed, the lower conical valve 48 is raised by the valve spring 54 and returns to its initial state.

In summary, the present invention adopts the configuration described in the claims, so that the drive shaft, which rotates at a low speed, is pushed forward by a piston through a special threaded spline, so that its rotation is further decelerated.
Therefore, the time for engagement between the two is slow, and once a portion of the engagement occurs, the threaded spline allows the engagement member to move forward on its own and complete engagement is quickly achieved, preventing impact damage. can be prevented.

Therefore, in a compressed air drive device that is characterized by sudden action, the engagement member moves forward in the same way as the compressed air operates, but the rotation caused by the compressed air is further decelerated to reduce the impact bending load at the time of engagement. It can be made into a suitable one.

[Brief explanation of drawings]

FIG. 1 is an overall schematic diagram, FIG. 2 is a sectional view of the air motor with the main valve body and air control valve omitted, and FIG. 3 is a sectional view of the main valve body and the air control valve. 5...Air control valve, 8...Pinion, 9...Ring gear, 12...Rotor, 29...Threaded spline,
30... Drive shaft, 39... Main valve body.

Claims (1)

[Claims] 1. In an air motor for starting an internal combustion engine, if an attempt is made to stop the rotation of the driven side of the air motor, the shaft moves forward through a threaded spline.
A drive shaft to be driven is provided, an engine engagement member is provided at the tip of the drive shaft, compressed air for the air motor is diverted, the air motor is rotated at a low speed with the diverted compressed air, and the compressed air is The driving shaft is advanced by a piston pressed by the piston, and the engaging member and the engine are partially engaged with each other while further decelerating the low-speed rotation of the engaging member due to the advancement,
A control device for an air motor for starting an internal combustion engine, characterized in that the threaded spline completes the engagement.