JPS643841Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Field of Application The present invention relates to an air supply circuit for an air cylinder that operates a dictation or the like.

BACKGROUND ART Conventionally, as shown in FIG. 1, this type of air supply circuit connects a factory air line 1 to an air tank 6 via a main circuit 5 equipped with a regulator 2, a check valve 3, and a stop valve 4. Air tank 6 to circuit 7
The valve 8 controls the supply to the air chamber 10a of the air cylinder 10 that operates the dictation pad 9, and the valve 8 can be freely switched between the supply position A and the discharge position B by the pilot cylinder 11.
Lower chamber 11a and upper chamber 11 of pilot cylinder 11
It is known that the pilot air from the pilot line 12 is controlled to be supplied via the solenoid valve 13 so that when it is supplied to the lower chamber 11a, it is at the supply position A, and when it is supplied to the upper chamber 11b, it is at the discharge position B.

In other words, the dictation pad 9 needs to be raised and lowered quickly as the press operation speeds up, and a large amount of air is pumped into the air cylinder 1 in a short period of time.
Since the valve 8 must be large in size to allow a large amount of air to flow through it, the valve 8 cannot be used as a solenoid valve, so the pilot cylinder 11 is used to switch the valve 8. In addition, when the dictation pad 9 is lowered, it quickly descends due to its own weight, but when it is raised, it rises against its own weight, which takes time, so the air chamber 10a of the air cylinder 10 Because it is necessary to supply air faster than to discharge air, when air is supplied to the lower chamber 11a of the pilot cylinder 11, the valve 8 is quickly switched to the supply position A by its own weight. .

Problems that the invention aims to solve However, with this structure, if the air pressure is lost due to damage to the factory air line 1 or failure of the compressor, the air pressure in the upper chamber 11b of the pilot cylinder 11 will drop and the valve 8 will close. It switches to supply position A due to its own weight.

For this purpose, the air chamber 10a of the air cylinder 10
This is dangerous because the air in the air tank 6 is supplied inside the piston 10b, causing the piston 10b to suddenly rise, causing the dictation pad 9, which is at the lower limit position, to rise.

The present invention was developed in view of the above circumstances, and its purpose is to provide an air supply circuit for an air cylinder in which the valve switches to the supply position by its own weight and the air cylinder does not operate even if the air pressure in the air source disappears. The goal is to provide the following.

Means and operation for solving the problem A check valve 14 is provided in the pilot line 12 that supplies air to the solenoid valve 13 to block the flow to the air source 1, and the outflow side of the check valve 14 is connected via a short-circuit path 16. and is connected to the air tank 6, and a check valve 17 is provided in the short-circuit path 16 to prevent the flow to the air tank 6 side.
Even if the air in the air source 1 runs out, the air in the air tank 6 is sent to the pilot cylinder 11 via the solenoid valve 13.
It was designed so that it could be supplied to

Embodiment An embodiment of the present invention will be described below with reference to FIG. Note that members that are the same as those in the prior art have the same reference numerals.

A check valve 14 and a stop valve 15 are provided in the pilot line 12, and the check valve 1
4 and the stop valve 15 are connected to the main circuit 5 via a short-circuit path 16, a check valve 17 is provided in the short-circuit path 16, and the check valve 14 is shaped to block the flow toward the factory airline 1 side,
The check valve 17 is shaped to block the flow to the main circuit 5.

Therefore, the air in the air tank 6 is transferred to the short circuit path 16.
It is supplied to the pilot line 12 via.

Therefore, air is supplied from the solenoid valve 13 to the upper chamber 11b of the pilot cylinder 11, and the valve 8
is in the discharge position B, even if the air pressure in the factory air line 1 disappears, the air pressure in the air tank 6 will flow through the solenoid valve 13 to the pilot cylinder 11.
Because the valve 8 is supplied to the upper chamber 11b, the valve 8 will not be in the supply position A, so the air cylinder 1
0 piston 10b does not move upward.

Effects of the invention Air from the air source 1 is stored in the air tank 6, and under normal conditions, pilot air from the pilot line 12 is pumped into the upper chamber 1 of the pilot cylinder 11 by the solenoid valve 13.
1b, the air is supplied to the lower chamber 11a, the valve 8 is switched, and the air in the air tank 6 is supplied to the air chamber 10a of the air cylinder 10 by the valve 8.

Furthermore, when the air in the air source 1 runs out, the air in the air tank 6 is supplied to the pilot line 12 through the short circuit 16, so the air pressure is transferred to the solenoid valve 13.
Since the air is supplied to the upper chamber 11b of the pilot cylinder 11 and the valve 8 is held at the discharge position B, the air cylinder 10 will not operate accidentally.

Also, since a check valve 17 is provided in the short circuit path 16, the air pressure in the pilot line 12 is not supplied to the air tank 6, and since a check valve 14 is provided in the pilot line 12, the air pressure in the air tank 6 is not supplied to the air tank 6. Air pressure does not flow out to the air source 1, so that when the air in the air source 1 runs out, the air pressure in the air tank 6 is transferred to the upper chamber 11b of the pilot cylinder 11 via the pilot line 12 and the solenoid valve 13. can be reliably supplied.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a conventional example, and FIG. 2 is an explanatory diagram showing an embodiment of the present invention. 1 is an air source, 6 is an air tank, 8 is a valve, 1
0 is the air cylinder, 12 is the pilot line, 1
4 and 17 are check valves, and 16 is a short circuit.

Claims (1)

[Scope of utility model registration request] The air source 1 is connected to the air tank 6, and the air in the air tank 6 is controlled to be supplied to the air chamber 10a of the air cylinder 10 via the valve 8 which is switched between the supply position A and the discharge position B by the pilot cylinder 11. 8 is in the supply position A when air is supplied into the lower chamber 11a of the pilot cylinder 11, and is in the discharge position B when air is supplied into the upper chamber 11b, and the lower chamber 11a of the pilot cylinder 11 is A check valve 14 is provided in the upper chamber 11b to control the supply of air pressure from a pilot line 12 connected to the air source 1 using a solenoid valve 13, and to prevent the air from flowing to the air source 1 in the pilot line 12. Also solenoid valve 13
An air supply circuit for an air cylinder, characterized in that the air cylinder side is connected to the air tank 6 via a short-circuit path 16, and a check valve 17 is provided in the short-circuit path 16 to prevent flow to the air tank 6 side.