JP2532625Y2 - Air compressor - Google Patents

Description

[Detailed description of the invention]

[0001]

The air compressor according to the present invention is incorporated in, for example, an air brake device for a large vehicle,
Used to create compressed air for braking.

[0002]

2. Description of the Related Art As a braking device for large vehicles such as large trucks and buses, an air brake device for generating a braking force by the force of compressed air is widely used. Such an air brake device stores compressed air produced by driving an air compressor by a driving engine of the above-mentioned large vehicle in an air tank, and at the time of braking, compresses the friction material by the force of the compressed air discharged from the air tank. Press against the inner peripheral surface of the drum or both sides of the disc.

[0003] The air compressor has a cylinder portion one end of which is closed by a partition wall, and a piston driven by the traveling engine to reciprocate in the cylinder portion and move an end surface of the air compressor toward and away from the partition wall. A suction hole and a discharge hole formed in the partition wall, and a suction valve provided in the suction hole portion and opened only when the end face of the piston is away from the partition wall; and an end face of the piston provided in the discharge hole portion. And a discharge valve that opens only when approaching the partition wall.

[0004] The air compressor thus configured is
With the reciprocation of the piston, the air sucked into the cylinder from the suction hole is compressed and sent out from the discharge hole toward the air tank. Accordingly, compressed air having a pressure corresponding to the valve opening pressure of the discharge valve is discharged from the discharge hole, and is sent into the air tank through a check valve.

[0005] By the way, while the piston always reciprocates when the traveling engine is rotating, when the compressed air is sufficiently stored in the air tank, the above-mentioned discharge is caused. Not only is it unnecessary to send out compressed air from the holes, but also the power of the running engine is wasted, the running performance of the vehicle is deteriorated, and the fuel consumption is deteriorated.

For this reason, conventionally, when a sufficient amount of compressed air is stored in the air tank, the cylinder is opened to the atmosphere to minimize the force required for the piston to reciprocate. A so-called unload mechanism for preventing the power of the traveling engine from being wasted is attached to the air compressor as described above.

For example, FIG. 9 shows an unloading mechanism described in Japanese Utility Model Publication No. Hei 2-10317. This unload mechanism keeps the suction hole open when a sufficient amount of compressed air is stored in the air tank. For this reason, an unload cylinder 4 is provided so as to face the suction hole 3 provided in the partition wall 2 which closes one end of the cylinder portion 1.

When a sufficient amount of compressed air is stored in the air tank, the compressed air is sent into the unload cylinder 4 to lower the unload piston 5 in FIG. Reed 7 constituting valve
(Leaf spring). As a result, the suction valve remains open regardless of the pressure in the cylinder portion 1,
The inside of the cylinder 1 communicates with the atmosphere, and the cylinder 1
The reciprocation of the piston 8 fitted inside can be performed with a light force.

FIG. 10 shows an unloading mechanism described in Japanese Utility Model Publication No. 2-32875. The unloading mechanism keeps the suction hole and the discharge hole closed when a sufficient amount of compressed air is stored in the air tank. For this reason, the unload cylinders 12 and 1 are opposed to the suction passage 9 communicating with the suction hole 3 provided in the partition wall 2 and the discharge passage 11 communicating with the discharge hole 10.
3 are provided.

When a sufficient amount of compressed air is stored in the air tank, the unload cylinders 12, 13
By sending compressed air into the unloading piston 1
4 and 15 are lowered in FIG.
The suction passage 9 and the discharge passage 11 are closed. As a result,
The inside of the cylinder part 1 is in a state of being shut off from the outside.

When the piston 8 reciprocates in the cylinder 1, when the piston 8 approaches the partition wall 2, power is consumed to move the piston 8 in order to compress the air in the cylinder portion 1. When the piston 8 moves away from the partition wall 2, the compressed air existing in the cylinder 1
, Power is sent from the air compressor to the engine.

[0012]

However, in the case of a conventional air compressor incorporating an unloading mechanism configured as described above, there are the following problems. First,
In the case of the structure of the first example shown in FIG. 9, since the lead 7 is pressed by the tip of the rod 6 during unloading, the lead 7 is easily damaged. That is, when the piston 8 is approaching the partition wall 2 and the lead 7 is pressed against the partition wall 2 and compressed air is sent into the unload cylinder 4, the tip of the rod 6 and the lead 7 A strong force acts between the lead 7 and a large load acts on the lead 7,
The durability of the lead 7 is impaired.

In the case of the structure of the second example shown in FIG.
Since the pressure fluctuation in the cylinder unit 1 is large, the operation of the traveling engine that drives the air compressor tends to be unstable. Further, depending on the operation timing of the unload cylinders 12 and 13, the inside of the cylinder portion 1 may become negative pressure with the movement of the piston 8, but when the inside of the cylinder portion 1 becomes negative pressure, the displacement of the air compressor is reduced. Lubricating oil for lubricating the part is easily sucked into the space 18 between the inner surface of the partition wall 2 and the end surface 8a of the piston 8. The lubricating oil sucked into the space 18 is sent into the air tank with a decrease in the pressure in the air tank, and is discharged from the cylinder unit 1. As a result, the consumption amount of the lubricating oil increases, and frequent lubrication is required, which is not preferable. The air compressor of the present invention eliminates any of the above disadvantages.

[0014]

The air compressor according to the present invention has a cylinder portion, one end of which is closed by a partition wall, and reciprocatingly moved by the cylinder portion to form an end face, similarly to the above-described conventional air compressor. A piston that moves the piston toward and away from the partition wall, a suction hole and a discharge hole respectively formed in the partition wall, and a suction valve that is provided in the suction hole portion and opens only when the end face of the piston moves away from the partition wall. And a discharge valve provided in the discharge hole portion and opened only when the end face of the piston approaches the partition wall.

In particular, in the air compressor of the present invention, the discharge valve has a support member provided on the outer surface side of the partition wall, a base end portion of which is supported by the support member, and a tip end portion of which is supported by the support member. It comprises a strip-shaped lead opposed to the discharge hole, and a drive mechanism for moving the support member toward and away from the outer surface of the partition wall. Then, when the drive mechanism approaches the support member to the outer surface of the partition wall, the tip of the lead elastically closes the discharge hole, and when the drive mechanism moves the support member away from the outer surface of the partition wall, The discharge holes are left open.

[0016]

In the case of the air compressor of the present invention configured as described above, when it is not necessary to send out compressed air, the driving mechanism moves the support member away from the partition wall and separates the tip of the lead from the discharge hole. This discharge hole is set to an open state. As a result, even when the piston approaches the partition wall, air is not compressed, and the piston can be moved with a light force.

When the piston reciprocates with the discharge hole kept open, air in the cylinder portion is supplied and discharged through the discharge hole. At this time, there is a possibility that oil and carbonized particles existing in the cylinder portion are sent out through the discharge holes. However, since the discharge hole communicates with the air tank and an air dryer equipped with a filter is provided between the cylinder and this air tank, the oil and carbonized particles sent from the cylinder may cause some problems. There is no.

Furthermore, since a strip-shaped lead is used and the base end of the lead is supported by the supporting member, the rigidity of the tip end of the lead can be maintained even if the thickness of the lead is increased. The opening of the discharge hole can be surely opened and closed by this lead without becoming excessive. Increasing the lead thickness
This leads to the improvement of the durability of the lead and the air compressor incorporating the lead.

[0019]

1 to 7 show a first embodiment of the present invention. A piston 8 is fitted in the cylinder portion 1 whose one end is closed by the partition wall 2 so as to be reciprocally movable. The piston 8 is driven by a traveling engine of the vehicle, and its end face 8a moves toward and away from the partition wall 2.

The partition wall 2 has a suction hole 3 and a discharge hole 10.
And form. A valve case 19 is fixed to the outer surface of the partition wall 2 so as to cover the holes 3 and 10. The inside of the valve case 19 is, as shown in FIGS.
The suction chamber 21 and the discharge chamber 22 are divided by a partition wall 20 extending in the diameter direction. The suction hole 3 is opened on the suction chamber 21 side, and the discharge hole 10 is opened on the discharge chamber 22 side. The valve case 19 has a suction chamber 21.
And a discharge port 24 (FIGS. 1 and 3) communicating with the discharge chamber 22 are provided.

As shown in FIGS. 2, 4 and 5, a strip-shaped lead 7 is attached to the lower surface of the partition wall 2, and the suction is opened only when the end face 8a of the piston 8 moves away from the partition wall 2. Make up the valve. That is, as shown in FIGS. 2 and 5, the base end of the lead 7 (see FIGS.
5, the right end of the lead 7 (FIG. 1,
The left end of the suction hole 3 faces the lower end opening of the suction hole 3 so that the suction hole 3 can be closed.

In the illustrated embodiment, a flange 26 formed on the outer peripheral edge of the open end of the cylinder 1
6, recesses 27 and 28 are formed. One of the recesses 27 (right side in FIGS. 5 and 6) is for preventing interference between the flange portion 26 and the screws 25, 25, and the other (left side in FIGS. Is for regulating the amount of displacement of the lead 7. That is, lead 7
The distal end of the lead 7 is inserted into the concave portion 28 so that the lead 7 can be elastically deformed within a range in which the distal end can move within the concave portion 28.

On the other hand, in the discharge chamber 22, there is provided a discharge valve 29 which opens only when the end face 8a of the piston 8 approaches the partition wall 2. The discharge valve 29 is provided at the base of a strip-shaped lead 31 (FIGS. 1, 3) on the lower surface of one end (left end in FIGS. 1 and 3) of a support member 30 provided in the discharge chamber 22.
Is supported and fixed by screws 32, 32.

As shown in FIG. 7, the supporting member 30 is a long rectangular plate having sufficiently larger bending rigidity than the lead 31. The lower half of the supporting member 30 has the other end (the right end in FIGS. 1 and 3). As it goes toward, it is gradually inclined upward. The lead 31 is supported by the lower surface of such a support member 30,
In the free state, the distal end (right end in FIGS. 1 and 3) is separated from the lower surface of the support member 30 to close the upper opening of the discharge hole 10, and a force is applied to the lower surface of the distal end through the discharge hole 10. In this case, the support member 30 is elastically deformed along the lower surface, and the upper end opening of the discharge hole 10 is opened.

Further, the discharge chamber 2 is placed on the upper surface of the valve case 19.
An unload cylinder 33 is provided in a portion corresponding to 2. The lower surface of the unload piston 34 fitted to the unload cylinder 33 and the upper surface of the center of the support member 30 are connected by a rod 35. Further, a compression spring 37 mounted between the upper end surface of the unload cylinder 33 and the upper surface of the unload piston 34 applies downward elastic force to the support member 30, and a driving mechanism together with the unload cylinder 33 is provided. Make up.

At the lower end of the unload cylinder 33, a compressed air inlet 36 is provided. When a sufficient amount of compressed air is stored in the air tank, the unloaded piston 34 is supplied through the inlet 36. On the lower side,
Compressed air can be sent freely.

Although not shown, an air dryer provided between the discharge port 24 and the air tank for removing moisture contained in the compressed air has an opening for opening the discharge port 24 to the atmosphere. A check valve is provided between the air dryer and the air tank, and a check valve for flowing compressed air only toward the air tank is provided. Then, the compressed air is sent to the unload cylinder 33, and at the same time, the release valve is opened. However, if this opening valve is provided in front of the air tank, it does not necessarily need to be provided in the air dryer.

In the case of the air compressor of the present invention configured as described above, when the amount of compressed air in the air tank is insufficient, the compressed air is sent into the unload cylinder 33 through the inlet 36. Do not do. As a result, the unload piston 34 descends due to the elastic force of the compression spring 37, and the support member 30 is pressed against the upper surface of the partition wall 2, and the lead 31 supported on the lower surface of the support member 30.
Covers the upper end opening of the discharge hole 10.

When the piston 8 is reciprocated in this state, air is sucked into the cylinder portion 1 from the suction hole 3 as the piston 8 descends, and compressed as the piston 8 rises. From the discharge hole 10 toward the air tank. The discharge valve 29 provided in the discharge hole 10 portion increases the pressure in the space 18 between the end face 8 a of the piston 8 and the lower surface of the partition wall 2 as the piston 8 rises. Then, the compressed air in the space 18 is sent out into the discharge chamber 22. Accordingly, compressed air having a pressure corresponding to the valve opening pressure of the discharge valve 29 (higher than the pressure in the air cylinder by the valve opening pressure) is discharged from the discharge hole 10, and the air tank is discharged through a check valve. Sent to.

If there is no need to send out compressed air,
With a control mechanism that operates according to the pressure in the air tank,
At the same time as the compressed air is fed into the unload cylinder 33, the release valve attached to the air dryer is opened. When the unload piston 34 is raised by sending compressed air into the unload cylinder 33, the support member 30 is pulled up by the rod 35, and the lower surface of the support member 30 is separated from the upper surface of the partition wall 2. As a result, the tip of the lead 31 supported on the lower surface of the support member 30 is
The discharge hole 10 is opened to the atmosphere through the above-mentioned opening valve, being separated from the upper end opening of the discharge hole 10. As a result,
Even when the piston 8 approaches the partition wall 2, no air compression is performed at all, and the movement of the piston 8 can be performed with a light force.

FIG. 8 shows a second embodiment of the present invention. In the first embodiment described above, the support member 3
0 was moved away from the partition wall 2 while being translated upward, whereas in the case of this embodiment, the support member 38 was
It is made to separate from the partition wall 2 while swinging.

That is, in the case of this embodiment, one end (the left end in FIG. 8) of the support member 38 is connected by the horizontal axis 39.
An arm piece 40 is fixed to one end of a support member 38 while being pivotally supported by the valve case 19. A compression spring 41 is provided between the upper end of the arm piece 40 and the inner surface of the valve case 19 to provide elasticity in a direction in which the support member 38 comes into contact with the upper surface of the partition wall 2.

The unload cylinder 33, which constitutes a driving mechanism together with the compression spring 41, is provided above the valve case 19.
They are provided in the lateral direction. The other end (the left end in FIG. 8) of the rod 35 having one end (the right end in FIG. 8) connected and fixed to the unload piston 34 fitted in the unload cylinder 33 is abutted against the arm piece 40.

In the case of this embodiment constructed as described above, when it is not necessary to send out the compressed air, the compressed air is sent into the unload cylinder 33 so that the support member 38 is moved upward about the horizontal axis 39. By swinging, the lower surface of the support member 38 is separated from the upper surface of the partition wall 2. Other configurations and operations are the same as in the first embodiment described above,
A duplicate description will be omitted.

[0035]

[Effect of the Invention] The air compressor of the present invention is configured and operates as described above, so that the components are not damaged by switching to unloading, and the pressure in the cylinder portion fluctuates during unloading. Since the operation is not performed, the operation state of the air compressor driving engine can be stabilized. Further, even when foreign matter such as oil or carbonized particles is discharged from the cylinder portion during unloading, the foreign matter does not have any adverse effect on the operation of other equipment. Furthermore,
Since the thickness of the lead can be increased, the durability of the lead and the air compressor incorporating the lead can be improved.

[Brief description of the drawings]

FIG. 1 is a sectional view taken along the line AA of FIG. 4, showing a first embodiment of the present invention.

FIG. 2 is a BB view of FIG. 1;

FIG. 3 is a view similar to CC.

FIG. 4 is a sectional view taken along the line DD of FIG. 1;

FIG. 5 is a sectional view taken along line EE of FIG. 2;

FIG. 6 is a partial perspective view showing an upper end opening of a cylinder unit.

FIG. 7 is a perspective view of a support member.

FIG. 8 is a sectional view similar to FIG. 1, showing a second embodiment of the present invention;

FIG. 9 is a sectional view showing a first example of a conventional structure.

FIG. 10 is a sectional view showing the second example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylinder part 2 Partition wall 3 Suction hole 4 Unload cylinder 5 Unload piston 6 Rod 7 Lead 8 Piston 8a End face 9 Suction passage 10 Discharge hole 11 Discharge passage 12 Unload cylinder 13 Unload cylinder 14 Unload piston 15 Unload piston Reference Signs List 16 valve body 17 valve body 18 space 19 valve case 20 partition wall 21 suction chamber 22 discharge chamber 23 suction port 24 discharge port 25 screw 26 flange portion 27 concave portion 28 concave portion 29 discharge valve 30 support member 31 lead 32 screw 33 unload cylinder 34 an Load piston 35 Rod 36 Inlet 37 Compression spring 38 Support member 39 Horizontal axis 40 Arm 41 Compression spring

Claims (1)

(57) [Scope of request for utility model registration] 1. A cylinder having one end closed by a partition wall, a piston reciprocating in the cylinder portion and moving an end face thereof toward and away from the partition wall, and a piston formed on the partition wall, respectively. A suction valve provided at the suction hole and the discharge hole, and at the suction hole portion, and opened only when the end face of the piston moves away from the partition wall; and only when the end face of the piston is provided at the discharge hole portion and approaches the partition wall. In the air compressor comprising an open discharge valve, the discharge valve includes a support member provided on the outer surface side of the partition wall, a base end portion of which is supported by the support member, and a distal end portion of which is formed of the discharge hole. a strip-shaped leads are opposed to, consists of a drive mechanism for perspective moving said supporting member against the outer surface of the partition wall, the tip of the lead, the driving mechanism is brought close to the support member to the outer surface of the partition wall In case, An air compressor, wherein the discharge hole is elastically closed, and the discharge hole is kept open when a driving mechanism moves the support member away from the outer surface of the partition wall.