JPH11315780A - Small quantity discharge pump drive and liquid supply method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drive method of a pump for discharging a constant minute amount of a metal working liquid and an efficient supply method to work tools and work parts of metal works, and to prevent stains due to using large quantities of metal working liquid around machinery, effects to humans, and production waste materials and the like. SOLUTION: The required quantity of liquid used for metal working is a minute quantity of from 3 cm<3> to 50 cm<3> every minute. A constant amount of this liquid is constantly sucked up from a tank and discharged using a reciprocating piston pump. For this, there are two pump chambers 4, 5 either in front and in back or to the left and right of a plunger 2. With both reciprocating movements of the plunger 2, constant and continuous intake and discharge is possible. Further, the difference in discharge amount of the liquid due to the structure of the two pump chambers 4, 5 is constantly and continuously made a constant liquid amount by changing the operating speed of the reciprocation of the plunger 2 so as to make intake and discharge possible.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the field of metal cutting using a metal working liquid.

[0002]

2. Description of the Related Art In conventional metal working, a working fluid is supplied at a rate of 20 minutes per minute in order to maintain the life of a tool and the accuracy of a metal workpiece.
1 to 30 liters were applied to the processed part. Further, the working fluid was repeatedly used until it became old. For this reason, in addition to the reduced efficiency of the processing fluid,
Due to the large amount of use, the liquid containing harmful substances is scattered, which has adversely affected not only the dirt around the machine but also the human body. Also, the liquor eventually had to be disposed of as a large amount of industrial waste. In order to solve the above-mentioned problem, a special machining liquid which is expensive but has good performance is sprayed by compressed air pressure from 3 cm ³ to 50 cm per minute depending on the type of metal working.
A small amount of cm ³ has been supplied to the processing tool and the processing part of the workpiece. However, even in this case, there is unevenness in the discharge of the liquid, the valuable liquid scatters in the air, and the sufficient effect of the processing liquid is not exhibited. In addition, dirt around the machine and adverse effects on the human body have also appeared.

[0003]

An object of the present invention is to make it possible to accurately and continuously suction and discharge a small amount of liquid of ³ cm ³ to 50 cm ³ per minute by using a piston pump. An object of the present invention is to effectively supply a processing liquid to a processing tool or a processing portion of a metal workpiece, thereby preventing industrial waste due to a large supply of the processing liquid, contamination around the machine, and an adverse effect on a human body.

[0004]

In FIG. 1, when the momentum of the piston shaft is S, the inner diameter of the cylinder is D, and the diameter of the piston shaft is d, the pump A chamber moves forward in the direction of arrow 12 of the piston shaft. Va = (π / 4)
× D ² × S. Further, in the backward movement of the piston shaft in the direction of arrow 13, the discharge amount of the liquid from the pump B chamber is V
b = (π / 4) × (D ² −d ² ) × S That is, the discharge amount in the backward movement is smaller than that in the forward movement by W = (π / 4) × d ² × S. Let Tc be the time of one forward and backward movement of the piston shaft. Exercise and return exercise times are the same Tc /
2. If the movement is also a constant velocity movement, the discharge amount Q per time from the pump becomes a pulse-like variable discharge amount as shown by the dotted line in FIG. This directly appears as a supply unevenness of the liquid to the processing portion, and the function of the processing liquid cannot be sufficiently exhibited. Therefore, as shown in FIG. 3, each time of the forward and backward movements of the piston shaft is not a simple symmetrical dotted line of Tc / 2, but the forward movement time is T1 and the backward movement time is T2, respectively. And T1: the ratio of T2 D ^2: by the ratio of (D 2 ^{-d 2),} as shown in Figure 2 the solid line, the discharge amount from the piston pump can always be a certain amount. In this way, the above-mentioned problem can be solved by supplying a small amount of the metal working liquid continuously and to a required constant amount to the working portion.

[0005]

[Embodiment] An embodiment of the present invention will be described below. As an example of the driving method of the piston shaft, FIG. 4 shows an example of driving by a groove cam (15) driven by an irregular motor (14) (usually a constant rotation motion). In this case, for one rotation of the groove cam (15), T
1. The rotation angle of the cam is assigned to the backward movement by the ratio of T2. The working fluid discharged by the piston pump having the above structure can be made continuous and constant, albeit in a small amount. In order to efficiently supply this liquid to the tool and the processing portion of the workpiece without unevenness, a method of actively dropping or spraying from a thin nozzle hole is adopted depending on the type of metal processing. As a result, the workability of metal and the use efficiency of the liquid are improved, and pollution around the machine due to the scattering of the liquid and pollution due to adhesion to the human body are eliminated.

[0006]

As described above, the present invention is constructed and operated as described above, so that a required and sufficient amount of the metal working fluid can be efficiently supplied to the working tool and the working portion of the workpiece. Furthermore, depending on the processing load at the time of metal processing, there may be cases where a larger amount or a smaller amount of metal processing liquid is required. For this purpose, the amount of the processing load is separately detected, and the motor ( By changing the rotation speed of 14), the amount of suction and discharge per hour from the piston pump can be changed, and the metal working fluid can be supplied promptly according to the required amount. It goes without saying that this is more effective when the piston pump is used.

[Brief description of the drawings]

FIG. 1 is a sectional view of the principle of a double-acting piston pump.

FIG. 2 is a graph showing that the amount of liquid discharged differs depending on the manner of movement of a piston shaft in a double-acting piston pump.

FIG. 3 is a graph showing movement of a piston shaft for discharging a fixed amount of liquid in a double-acting piston pump.

FIG. 4 is a simplified diagram showing an embodiment of a method of driving a piston shaft.

[Explanation of symbols]

1. Piston shaft 2. Plunger 3. Cylinder 4. Pump A room 5. Pump B room 6. Suction side 7. Discharge side 8a, 8b. Suction side check valve 9a, 9b. Discharge side check valve 10a, 10b. Suction pipes for pump A and B chambers 11a, 11b. 11. Discharge pipeline of pump A chamber and B chamber 12. Forward movement direction of piston shaft 13. Return direction of piston shaft Motor 15. Groove cam D Inner diameter of cylinder 3 d Diameter of piston shaft Q Discharge amount per hour from pump S Momentum of piston shaft Tc Time of forward and backward movement of piston shaft T1 Time of forward movement of piston shaft T2 Return movement of piston shaft Va Vacuum discharge amount from pump A chamber Vb Discharge amount of liquid from pump B chamber W Difference between pump A chamber and B chamber discharge rate due to forward and backward movements of piston shaft

Claims (2)

[Claims] 1. A method of driving a piston pump for supplying a metal working liquid which continuously sucks and discharges a fixed amount. 2. Using the pump according to claim 1,
A method of supplying a metal working liquid in which a metal working liquid is dropped or sprayed onto a processing portion of a metal workpiece and a tool.