JPH08177811A - Oil temperature control device for hydraulic unit - Google Patents

Abstract

PURPOSE: To provide an oil temperature control device of a hydraulic unit which suppresses a cost without reducing a pump of a cooling tower. CONSTITUTION: A cooler 41 is arranged on the way of a piping 31 through which oil returns from a hydraulic cylinder 7 to a tank 33. An oil temperature control device 45 controls temperature of oil passing the cooler 41. A three- directional valve 63 is arranged on the way of cooling circuits 47, 49 which connect the cooler to a pump 53 of a cooling tower 51.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil temperature control device for a hydraulic unit which operates a ram cylinder of a hydraulic punch press.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 2, for example, a hydraulic turret punch press 1 as a hydraulic punch press is provided with rotatable upper and lower turrets 3 and 5, and the upper turret 3 is provided with the upper turret 3. A punch P is attached to the lower turret 5, and a die D is attached to the lower turret 5.

A hydraulic cylinder device 7 is fixed to a frame 9 above the punch P. The hydraulic cylinder device 7 has a piston 13 in the cylinder body 11, and the piston rod 1 integrated with the piston 13
A ram 17 is provided at the tip of 5. Inside the cylinder main body 11, upper and lower cylinder chambers 19U and 19D are formed with the piston 13 as a boundary.

Further, a hydraulic circuit 21 is provided for supplying or discharging hydraulic pressure to the lower cylinder chambers 19U and 19D. That is, one ends of the pipes 23 and 25 are connected to the upper and lower cylinder chambers 19U and 19D, and the other ends of the pipes 23 and 25 are connected to the B and A ports of the servo valve 27.

One ends of pipes 29 and 31 are connected to the P and R ports of the servo valve 27, and the pipe 2
The other ends of 9, 31 are communicated with the tank 33. A pump 35 and a filter 37 are provided in the middle of the pipe 29, and a motor 39 is connected to the pump 35. A cooler 41 is provided in the middle of the pipe 31. The tank 33 is provided with an oil temperature sensor 43 to monitor the oil temperature in the tank 33.

With the above structure, when the motor 39 is driven to operate the pump 35, the oil in the tank 33 is discharged to the pipe 29 via the filter 37. The oil discharged to the pipe 29 is the solenoid SOL of the servo valve 27.
To connect the P port and the B port, and the R port and the A port to each other by operating the
It is supplied to the upper cylinder chamber 19U. The oil in the lower cylinder chamber 19D is returned to the tank 33 via the pipes 25 and 31.

By supplying oil to the upper cylinder chamber 19U, the ram 17 provided at the tip of the piston rod 15 is lowered via the piston 13.

Further, the oil discharged to the pipe 29 flows into the pipe 25 by operating the solenoid SOL of the servo valve 27 to connect the P port and the A port and the R port and the B port, and then the lower cylinder. Supply to chamber 19D. The oil in the upper cylinder chamber 19U is returned to the tank 33 via the pipes 23 and 31.

By supplying oil to the lower cylinder chamber 19D, the ram 17 provided at the tip of the piston rod 15 is raised via the piston 13.

Therefore, the ram 17 strikes the punch P by the vertical movement of the ram 17, and the work W on the die D is punched by the cooperation of the punch P and the die D.

Thus, the hydraulic turret punch press 1
In order to eliminate vibration of the ram 17 or to perform a high-level forming process when a large amount of oil is flown into the upper and lower cylinder chambers 19U and 19D, a cooler 41 provided in the middle of the pipe 31 is used. The oil returned to the tank 33 is cooled.

In order to control the oil temperature of the oil cooled by the cooler 41, the cooler 41 is provided with an oil temperature control device 45. That is, as shown in FIG. 2, one ends of the pipes 47 and 49 are connected to the cooler 41, and the other ends of the pipes 47 and 49 are connected to the pump 53 provided in the cooling tower 51. Has been done. A motor 55 is connected to the pump 53. A two-way valve 57 and a water amount sensor 59 are provided in the middle of the pipe 49.

With the above structure, the motor 55 is driven and the pump 53 is operated to cause the water in the cooling tower 51 to flow into the cooler 41 via the pipe 49. Cooler 41
The water, which has been cooled with oil through the pipe 47, goes through the cooling tower 5
It will be set back to 1.

The water flowing through the cooler 41 is O of the two-way valve 57.
The oil temperature is controlled by being turned on and off depending on N and OFF, and the water amount is checked by the water amount sensor 59.

[0015]

In the conventional oil temperature control device 45 described above, when the water from the cooling tower 51 is shut off by turning off the two-way valve 57 in order to control the oil temperature, the cooling tower 51 is cooled.
The pump 53 of idling. As a result, there is a problem that the water of the pump 53 generates heat and the life of the pump 53 is shortened.

In order to solve this problem, it is also known that the oil temperature control device 45 is partially improved as shown in FIG. In FIG. 3, the same parts as those in FIG. 2 are designated by the same reference numerals and overlapping description will be omitted.

In FIG. 3, a two-way valve 61 serving as a bypass circuit is connected to the pipe 47 and the pipe 49.

Therefore, by driving the motor 55 to operate the pump 53 and turning on the water in the cooling tower 51 through the pipe 49 and turning on the two-way valve 57, the water flows into the cooler 41. At this time, the two-way valve 61 is OFF
The water whose oil has been cooled by the cooler 41 is returned to the cooling tower 51 through the pipe 47.

The water flowing to the cooler 41 is supplied to the OF of the two-way valve 57.
When shutting off at F, the water is piped 49, the two-way valve 61 and the pipe 47 by turning on the two-way valve 61.
Since it is returned to the cooling tower 51 and circulated through it, the pump 53 does not run idle, but there is a problem that an extra one-way valve 61 is required and the cost increases.

An object of the present invention is to provide an oil temperature control device for a hydraulic unit which does not shorten the life of the pump of the cooling tower and does not increase the cost.

[0021]

In order to achieve the above object, an oil temperature control device for a hydraulic unit according to a first aspect of the present invention is provided with a cooler in the middle of a pipe through which oil is returned from a hydraulic cylinder to a tank. An oil temperature control device for controlling the oil temperature of the oil flowing through, characterized in that a three-way valve is provided in the middle of a cooling circuit connecting the cooler and the pump of the cooling tower.

According to a second aspect of the present invention, there is provided an oil temperature control device for a hydraulic unit, wherein the hydraulic cylinder is a ram cylinder of a hydraulic punch press.

[0023]

With the oil temperature control device of the hydraulic unit as described above, the cooler is provided in the middle of the pipe for returning the oil from the hydraulic cylinder to the tank, so that the oil is cooled by the cooler.

The water flowing to the cooler can be made to flow from the cooling tower to the cooler by activating a three-way valve provided in the middle of the cooling circuit connected to the cooler and the cooling tower, and to the cooler. When shutting off, the water is circulated in the cooling circuit and the cooling tower without flowing water to the cooler by the operation of the three-way valve.

Therefore, even when the water is shut off to the cooler, the pump of the cooling tower is operated without idling, so that the life of the pump is not shortened. Moreover, since the three-way valve is inexpensive, the cost does not increase more than in the past.

[0026]

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a schematic view showing an oil temperature control device in a hydraulic circuit of, for example, a turret punch press 1 as a hydraulic punch press according to an embodiment of the present invention.
In FIG. 1, the same parts as those in FIG. 2 described in the prior art are designated by the same reference numerals and overlapping description will be omitted.

In FIG. 1, an oil temperature control device 45 is provided.
A three-way valve 63 is provided in the middle of the pipe 49 in. The P port of this three-way valve 63 is the water amount sensor 5
9 side piping 49, A port is cooler 41 side piping 49
It is connected to the. Further, one end of the pipe 65 is connected to the B port of the three-way valve 63, and the other end of the pipe 65 is connected in the middle of the pipe 47.

With the above structure, when the motor 55 in the cooling tower 51 is driven to operate the pump 53, the water in the cooling tower 51 flows into the pipe 49.
When the solenoid SOL1 of the three-way valve 63 is turned on to connect the R port and the A port, the water flowing in the pipe 49 flows into the cooler 41, the oil in the pipe 31 is cooled and returned to the tank 33. The water used in the cooler 41 flows into the pipe 47 and is returned to the cooling tower 51.

Solenoid SOL2 of the three-way valve 63
When the P port and the B port are made to communicate with each other by operating, the water flowing in the pipe 49 is returned to the cooling tower 51 via the pipes 65 and 47. At this time,
Since the water from the cooling tower 51 does not flow into the cooler 41 and is shut off and circulated through the pipes 49, 65, 47 and the cooling tower 51, the pump 53 of the cooling tower 51 is operated without idling, so that the life of the pump 53 is shortened. Without reducing the oil temperature, for example 30-4
It can be controlled at 0 ° C. Moreover, the pump 53 can have the same life as when the oil temperature is not controlled.

The oil temperature in the tank 33 is measured by an oil temperature sensor 43.
In addition to being able to monitor the amount of water in the pipe 49, the amount of water in the pipe 49 can be confirmed by a water amount sensor 59. Since the three-way valve 63 is provided to prevent the idling of the pump 53 without using two two-way valves, the cost of the control device 45 does not increase, and the control device 45 does not have to use two two-way valves. ~
It can be manufactured at a low cost of about 30%.

The oil temperature control device 45 of this hydraulic unit is used to cool the oil temperature in the hydraulic circuit 21 when the work W is punched by the hydraulic turret punch press 1, so that the ram 17 vibrates. Can be eliminated or a high degree of molding can be performed.

The present invention is not limited to the above-mentioned embodiments, but can be implemented in other modes by making appropriate changes.

[0034]

As can be understood from the above description of the embodiment, according to the invention according to claim 1, since the cooler is provided in the middle of the pipe for returning the oil from the hydraulic cylinder to the tank, Is cooled by a cooler.

The water flowing to the cooler can be made to flow from the cooling tower to the cooler by activating a three-way valve provided in the middle of the cooling circuit connected to the cooler and the cooling tower, and to the cooler. When shutting off, the water is circulated in the cooling circuit and the cooling tower without flowing water to the cooler by the operation of the three-way valve.

Therefore, even when the water is shut to the cooler, the pump of the cooling tower is operated without idling, so that the oil can be controlled without shortening the life of the pump. Further, since the three-way valve is inexpensive, the control device can be manufactured at a low cost without increasing the cost as compared with the conventional one.

According to the second aspect of the invention, by using the hydraulic cylinder as the ram cylinder of the hydraulic punch press, the oil temperature can be controlled by this oil temperature control device, and vibration of the ram can be eliminated. Or
Alternatively, a high degree of molding processing can be performed.

[Brief description of drawings]

FIG. 1 is an explanatory diagram in which an oil temperature control device for a hydraulic unit of the present invention is provided in a hydraulic circuit of a cylinder device in a hydraulic turret punch press.

FIG. 2 is an explanatory diagram in which an oil temperature control device for a conventional hydraulic unit is provided in a hydraulic circuit of a cylinder device in a hydraulic turret punch press.

FIG. 3 is an explanatory diagram in which an oil temperature control device for a conventional hydraulic unit, which replaces that shown in FIG. 2, is provided in a hydraulic circuit of a cylinder device in a hydraulic turret punch press.

[Explanation of symbols]

 1 Hydraulic Turret Punch Press (Hydraulic Punch Press) 7 Fluid Cylinder Device 11 Cylinder Body 17 Ram 19U Upper Cylinder Chamber 19D Lower Cylinder Chamber 21 Hydraulic Circuit 31 Piping 33 Tank 41 Cooler 43 Oil Temperature Sensor 45 Hydraulic Control Device 47, 49 Piping 51 Cooling Tower 53 pump 55 motor 63 three-way valve 65 piping

Claims (2)

[Claims] 1. An oil temperature control device for controlling an oil temperature of oil flowing through the cooler by providing a cooler in the middle of a pipe through which oil is returned from a hydraulic cylinder to a tank,
An oil temperature control device for a hydraulic unit, characterized in that a three-way valve is provided in the middle of a cooling circuit connecting the cooler and the pump of the cooling tower. 2. The oil temperature control device for a hydraulic unit according to claim 1, wherein the hydraulic cylinder is a ram cylinder of a hydraulic punch press.