JPS63197568A - Liquid supply apparatus - Google Patents

Abstract

PURPOSE:To continuously and rapidly supply a predetermined amount of a fluid under predetermined pressure, by a method wherein one of left and right small diameter cylinder apparatus emits a fluid and the other one of them sucks the fluid when the large diameter piston of a large diameter hydraulic cylinder apparatus moves left and right. CONSTITUTION:When the pressure oil sucked up by a pump P flows in the right end side of a large diameter hydraulic cylinder apparatus 2, a large diameter piston 4 moves to the left and, with this movement of said piston 4, left and right small diameter pistons 5a, 6a also move to the left under the same pressure. Hereupon, the inner volume of a right-hand small diameter cylinder apparatus 10 increases and not only paint is sucked in the apparatus 10 from a fluid suction line 13 but also the inner volume of a left-hand small diameter cylinder apparatus 9 decreases and the paint in the apparatus 9 is emitted to a fluid emitting line 16 to be supplied to an air spray gun A. When a change- over valve 22 is automatically changed over and the pressure oil flows in the left end side of the apparatus 2, the large diameter piston 4 moves to the right and, at this time, the paint is sucked in the left-hand small diameter cylinder apparatus 9.

Description

Detailed Description of the Invention A0 Object of the Invention (1) Industrial Application Field The present invention relates to a fluid supply device, and particularly to a fluid supply device suitable for continuously supplying a predetermined amount of fluid at a predetermined pressure. Regarding.

For example, when painting using a paint spraying device such as an air spray gun or an airless spray gun, such a fluid supply device supplies a predetermined amount of paint to the paint spraying device in order to maintain a constant thickness of the paint film. It is used to continuously supply water at a predetermined pressure.

Although the fluid supply device is suitable for supplying high viscosity paint to a paint injection device, it can also be used to supply other fluids to desired locations.

(2) Prior Art For example, the body of an automobile is coated with an undercoat, an intermediate coat, and a topcoat, and these coatings can considerably suppress the occurrence of rust. However, when a car is driven on a rough road, flying stones, etc. can hit the underside of the car body or the bottom of the door (side sill), damaging the paint film (chipping). Mackerel may occur. To prevent such chipping,
High viscosity paint containing polyvinyl chloride resin (PVC) as a main component is applied to the underside of the floor, side sills, etc. When applying this high viscosity paint, make sure that the thickness of the paint film is uniform, and avoid the reference holes where locating pins are inserted when transporting the car, and the mounting holes of various parts. etc. are required.

As a fluid supply device for supplying paint to a paint spraying device used in such a case, an air-type paint booster 01 as shown in FIG. 3 is known. This air paint booster 01 includes a large diameter cylinder device y102 and a small diameter cylinder device 03. Inside the large-diameter cylinder device 02, there is a large-diameter piston 02a and a compression spring 0 that biases the large-diameter piston 02a in one direction (upward in FIG. 3).
2b are arranged. And that large diameter piston 0
A chamber on the side opposite to the side where the compression spring 02b is disposed in 2a is connected to an air supply source 06 via an electromagnetic switching valve 04 and an air pressure adjustment unit 05. Further, a small diameter piston 03a is disposed inside the small diameter cylinder device 03, and a rear surface (upper surface in FIG. 3) of this small diameter piston 03a.
and the front surface (lower surface in FIG. 3) of the large diameter piston 02a are connected at a loft 07. This loft 07 is provided with a protrusion 07a. In addition, the rod 07
Two limit switches 08 and 09 are arranged along the ridge, and these two limit switches 08 and 09 are operated by the projection 07a.

The small diameter piston 03a in the small diameter cylinder device 03
A chamber on the front side of is a paint suction line 01 connected to a paint tank 012 via a check valve 010, a cock 011, etc.
3, and is also connected to a paint discharge line 016 which is connected to an air spray gun 015 via a cock 014 or the like.

When the electromagnetic switching valve 04 is in the position shown in FIG. 3, the large diameter piston 02a is
, the rod 07 and the small-diameter piston 03a move backward (move upward in FIG. 3), and at this time, paint is sucked into the small-diameter cylinder device 03.

In addition, as the rod 07 moves, the protrusion 07a operates the limit switches 08, 09 to switch the electromagnetic switching valve 04, and the electromagnetic switching valve 04 moves from the state shown in the figure to a lower position. When switched to , air is supplied from the air supply source 06 into the large diameter cylinder device 02 via the electromagnetic switching valve 04 . At this time, the large-diameter piston 02a10 and the small-diameter piston 07 move forward, and the paint in the small-diameter cylinder device 03 is supplied to the air spray gun 015 via the paint discharge line 016.

(3) Problems to be Solved by the Invention However, the conventional fluid supply device such as the air-type paint booster o1 has the following problems.

(2) The pressure of the air supply source 06 is normally about 6 kg/c+4, and there is a limit to the air supply speed to the large diameter cylinder device 02.

■ Because the diameter of the large-diameter cylinder device 02 cannot be made very large due to the above-mentioned reason and space constraints, there is a limit to the pressure increase ratio (the ratio of the diameter of the large-diameter cylinder device 02 to the diameter of the small-diameter cylinder device 03). There is. Therefore, there is a limit to the paint supply speed.

(2) During the period when paint is being sucked into the small-diameter cylinder device 03, paint cannot be discharged into the paint discharge line 016.

Therefore, there is a loss time in replenishing the paint.

■ When performing automatic painting using a robot, etc., the above ■.

Due to reasons (1) and (2), the amount of paint supplied cannot follow the coating speed, and it is not possible to shorten the coating time, which is an advantage of automatic coating.

■ Because the pressure of the air supply source 06, that is, the original pressure, is low, the discharge fluctuations between the beginning and the end of paint discharge are large, and it is difficult to obtain a constant discharge (therefore, the thickness of the paint film becomes uneven, so it is difficult to reuse the paint). Painting may be required, which reduces work efficiency.In addition, the coating width may be adjusted by controlling the air pressure for spraying, as in the air spray gun described in JP-A-61-171567. In this case, it is not possible to obtain a desired coating width due to variations in paint discharge.

The present invention has been made in view of the above-mentioned problems, and provides a fluid supply device suitable for rapidly supplying a predetermined amount of fluid (for example, paint) to a predetermined location continuously and at a predetermined pressure. The purpose is to

B6 Structure of the invention (Means for solving the 11 problems) In order to achieve the above object, the fluid supply device of the present invention includes:
a large-diameter cylinder; a large-diameter piston that moves inside the large-diameter cylinder between its left and right ends; and a pair of left and right pistons connected to both the left and right sides of the large-diameter piston and protruding from both left and right end walls of the large-diameter cylinder. a large-diameter hydraulic cylinder device consisting of a piston rod; a small-diameter piston provided at both ends of the left and right piston rods, and a small-diameter cylinder provided on the outer periphery of the small-diameter piston; a pair of left and right small-diameter cylinder devices whose internal volume decreases when the other one increases; and a fluid suction line and a fluid discharge line connected to each of the left and right small-diameter cylinder devices via a flow direction control circuit. , the flow direction control circuit is
It is possible to move fluid from the fluid suction line to the left and right small diameter cylinder devices and from the left and right small diameter cylinder devices to the fluid discharge line, but it is impossible to move fluid in the opposite direction. It is characterized by being configured as follows.

(2) Function The present invention having the above-described configuration is such that when the large-diameter piston of the large-diameter hydraulic cylinder device moves to either the left or right side due to the action of oil pressure, one of the left and right small-diameter cylinder devices moves. The small diameter cylinder device decreases its internal volume and discharges the fluid therein to the fluid discharge line via the flow direction control circuit, and the other small diameter cylinder device increases its internal volume and discharges the fluid therein to the fluid discharge line via the flow direction control circuit. Fluid is sucked into the interior from the fluid suction line through the flow direction control circuit. When the large-diameter piston moves in the opposite direction to the left and right sides due to the action of oil pressure, the actions of the left and right small-diameter cylinder devices are reversed. Therefore, during the operation period of the large-diameter hydraulic cylinder device, fluid is supplied to the fluid discharge line regardless of whether the large-diameter piston moves in the left or right direction. Therefore, the fluid sucked into either the left or right small diameter cylinder device from the fluid suction line is continuously supplied to the fluid discharge line. Since the large-diameter hydraulic cylinder device is operated by hydraulic pressure, the discharge fluctuation of the small-diameter cylinder device is small.

(3) Example An example of the present invention will be described below with reference to FIGS. 1 and 2.

The fluid supply device 1 shown in FIG. 1 has a large diameter hydraulic cylinder device 2. The fluid supply device 1 shown in FIG. The large diameter hydraulic cylinder device 2 includes:
A large diameter cylinder 3 having a left end wall 3a and a right end wall 3b, a large diameter piston 4 that moves inside this large diameter cylinder 3 between its left and right ends, and a left side connected to both left and right sides of this large diameter piston 4, respectively. It is composed of a piston rod 5 and a right piston rod 6. The left piston rod 5 and the right piston rod 6 extend outward through the left end wall 3a and right end wall 3b of the large diameter cylinder 3, respectively. The left end of the left piston rod 5 and the right end of the right piston rod form a left small diameter piston 5a and a right small diameter piston 6a, respectively. A left small diameter cylinder 7 and a right small diameter cylinder 8 are disposed on the outer peripheries of the left small diameter piston 5a and the right small diameter piston 6a, respectively. These left side small diameter cylinder 7 and right side small diameter cylinder 8 are
The large diameter cylinder 3 is supported by appropriate supporting members.
It is connected to the left end wall 3a and the right end wall 3b. The left small diameter piston 5a and the right small diameter piston 6a are
It is inserted into the left side small diameter cylinder 7 and the right side small diameter cylinder 8 from the openings 7a and 8a on the inner end side thereof. And the left small diameter piston 5a
A left side small diameter cylinder device 9 is constituted by the left side small diameter cylinder 7, and a right side small diameter cylinder device 1° is constituted by the right side small diameter piston 6a and the right side small diameter cylinder 8. Therefore, when the large diameter piston 4 moves left and right, one of the small diameter cylinder devices 9 (10) of the left small diameter cylinder device 9 and the right small diameter cylinder device 1O.
) is decreased, and the other small diameter cylinder device 10(9) has an increased internal volume.

Inside each of the left and right small-diameter cylinder devices 9 and 10, fluid is sucked through the left side fluid connection line 11 and the left side fluid suction check valve 11, and the right side fluid connection line air and the right side fluid suction check valve 12. Connected to line 13. Both of the left and right fluid suction check valves 11 and 12 allow fluid to move from the fluid suction line 13 to the left and right small diameter cylinder devices 9 and 10, but do not allow fluid to move in the opposite direction. making it impossible. and,
The fluid suction line 13 is connected to the paint tank T.

Further, the insides of the left and right small-diameter cylinder devices 9 and 10 are supplied with fluid through a left fluid connection line II and a left fluid discharge check valve 14, and a right fluid connection line 12 and a right fluid discharge check valve 15, respectively. It is connected to the discharge line 16. The left and right fluid discharge check valves 14 and 15
Both of the left and right small diameter cylinder devices 9 and lO
Although it is possible for fluid to move from to the fluid discharge line 16, it is impossible to move fluid in the opposite direction.

Said left and right fluid connection lines 'I+#! , a fluid suction check valve 11.12, a fluid discharge check valve 14.15, etc., constitute a flow direction control circuit N.

The fluid discharge line 16 is connected to the accumulator 1.
6a, and is also connected to the air spray gun A. This air spray gun A has fluid discharge line 1.
High viscosity paint is supplied from 6, and air is also supplied from spraying air source B as usual, and is used to spray paint the side sill C of the automobile body. In addition, in FIG. 2, D indicates a door of an automobile.

A left hydraulic boat 17 and a right hydraulic boat 18 are provided near the left end wall 3a and right end wall 3b of the large diameter hydraulic cylinder device 2, and these hydraulic boats 17 and 1
8 is the left hydraulic connection line! , and the high pressure side hydraulic line 2. through the right side hydraulic connection line 14 and the automatic switching valve 19. Or the low pressure side hydraulic line! ,It is connected to the. The high-pressure side hydraulic line 15 includes a strainer S, an electric motor EM, and a variable discharge pump P, and the low-pressure side hydraulic line 2. is connected to the oil sump.

Furthermore, a left operating rod 20 and a right operating rod 21 are disposed on the left end wall 3a and right end wall 3b of the large diameter hydraulic cylinder device 2 so as to be able to pass through them so as to be movable left and right. A left side switching valve 22 is connected to the outer end of the left side operating rod 20, and the left side switching valve 22 moves in conjunction with the movement of the left side operating rod 20. Further, a right side switching valve 23 is provided at the outer end of the right side operating rod 21.
are connected to each other, and this right-side switching valve 23 is adapted to move in conjunction with the movement of the right-side operating rod 21.

A left side pilot line 17 and a right side pilot line I18 are provided between the high pressure side hydraulic line 1 and the left side switching valve 22 and the right side switching valve 23, respectively.
is provided. Further, the left side switching valve 22 and the right side switching valve 23 are respectively provided with a left side return line l and a right side return line 11° connected to the oil reservoir.

Further, between the left-side switching valve 22 and the automatic switching valve 19 and the right-side switching valve 23, a left-side pilot line 1. is provided, and the right side switching valve 2
A right pilot line 11□ for pilot operating the automatic switching valve 19 and the left switching valve 22 is provided between the automatic switching valve 19 and the left switching valve 22.

Next, the operation of the embodiment of the present invention having the above-described configuration will be explained.

When the electric motor EM is operated at a constant rotational speed with the automatic switching valve 19, the left switching valve 22, and the right switching valve 23 in the state shown in FIG. , flows from the high pressure side hydraulic line 15 through the automatic switching valve 19 and the right hydraulic connection line 14, and from the right hydraulic bow 18 to the right end side of the large diameter hydraulic cylinder device 2.

At this time, since the large diameter piston 4 receives pressure over a large area, it receives a large force as a whole and moves to the left. Along with this movement of the large diameter piston 4, the left and right small diameter pistons 5
a and 6a also move to the left and right under the same force as a whole. Then, the internal volume of the right small diameter cylinder device 10 increases, and the internal volume of the left small diameter cylinder device 9 decreases.

At this time, inside the right small-diameter cylinder device 10, there is a fluid suction line 13 from the paint tank T, a right fluid suction check valve 12, and a right fluid connection line 1! The paint inside the left small-diameter cylinder device 9 passes through the left fluid connection line 11, the left fluid discharge check valve 14, and the fluid discharge line 16 to the air spray gun A. is supplied to At this time, the surface pressure (pressure per unit area) acting on the left small-diameter piston 5a is greater than the surface pressure acting on the large-diameter piston 4, so the fluid discharge line 16 and air spray gun A can supply paint with stable discharge pressure.

In this state, the high pressure side hydraulic line 1 is connected to the right side pilot line J, and the right side pilot line ll! via the right side switching valve 23. It is connected to the.

Therefore, the right pilot line lI! is supplied with pilot pressure oil, and this pilot pressure oil causes the automatic switching valve 19 and the left switching valve 22 to switch to the first
It is maintained in the state shown in the figure. Note that the right side switching valve 23 is maintained in the illustrated state by a positioning biasing spring.

The large diameter piston 4 moves to the left end, and the left operating rod 20
When pushed to the left, the position of the left-side switching valve 22 is automatically switched. In this switched state, the high-pressure side hydraulic lines are connected to the left side pilot line J, and the left side viroft line through the left side switching valve 22! , is connected to. Therefore, pilot pressure oil is supplied to the left pilot line l111, and by this pressure oil, the automatic switching valve 19 and the right switching valve 23 are automatically switched to a state different from the state shown in FIG. Become. Then, the high pressure side hydraulic line 15 is connected to the automatic switching valve 19, the left side hydraulic connection line 13 and the left side hydraulic boat 1.
It is connected to the left end side inside the large diameter hydraulic cylinder device 2 via 7. At this time, the pressure oil sucked up from the variable discharge pump P flows into the left end side of the large diameter hydraulic cylinder device 2. At this time, the large diameter piston 4 moves to the right, and as the large diameter piston 4 moves to the right, the internal volume of the left small diameter cylinder device 9 increases, and the internal volume of the right small diameter cylinder device IO increases. Decrease. At this time, inside the left small-diameter cylinder device 9, there are a fluid suction line 13 from the paint tank T, a left fluid suction check valve 11, and a left fluid connection line E.

Through, the paint is sucked in and the paint inside the right small diameter cylinder device 10 is transferred to the right fluid connection line 1!
, right side fluid discharge check valve 15, and fluid discharge line 1
6 and is supplied to the air spray gun A. next,
The large diameter piston 4 moves to the right end, and the right side operating rod 2
When 1 is pressed, the right switching valve 23, automatic switching valve 19, and left switching valve 22 are automatically switched in the same manner as when the left operating rod 20 is pushed. Therefore, the large diameter piston 4 automatically reciprocates left and right.

Then, regardless of whether the large diameter piston 4 moves leftward or rightward, the fluid discharge line 16 has a
Paint will be supplied. That is, the fluid discharge line 16 is continuously supplied with paint. Then, when switching the moving direction of the large diameter piston 4,
Pulsations occur momentarily in the paint discharged into the fluid discharge line 16, but the instantaneous pulsations are caused by the
Absorbed by 6a.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the embodiments described above, and various design changes can be made without departing from the scope of the invention described in the claims. Is possible.

For example, instead of continuously supplying paint to the air spray gun A, the fluid supply device 1 is capable of supplying fluid other than paint to a necessary location, and the left side switching valve 22 and The right side switching valve 23 may be configured to perform the switching operation electrically using a limit switch or the like, instead of performing the switching operation in conjunction with the left operating rod 20 and the right operating rod 21. It is possible. Furthermore, the flow direction control circuit N can be configured using an electromagnetic switching valve or the like that is switched according to the moving direction of the large diameter piston 4 instead of using a reverse valve. . Furthermore, small diameter pistons 5a and 6 are provided on the outer end surfaces of the left and right piston rods 5 and 6.
Instead of forming the piston rods 5 and 6, it is also possible to separately connect small-diameter pistons to the outer ends of the left and right piston rods 5 and 6.

C0 Effects of the Invention According to the fluid supply device of the present invention described above, either the left or right small diameter cylinder device operated by hydraulic pressure always discharges fluid to the fluid discharge line, so a predetermined amount of fluid is delivered to a predetermined location. Fluid can be continuously supplied at a predetermined pressure.

[Brief explanation of the drawing]

Fig. 1.2 shows an embodiment of the device of the present invention.
The figure is the overall circuit diagram, and Figure 2 is a diagram showing an example of the usage state of the air spray gun supplied with paint from the device of the present invention.
FIG. 3 is an overall circuit diagram of a conventional fluid supply device. 2... Large diameter hydraulic cylinder device, 3... Large diameter cylinder, 3a... Left end wall, 3b... Right end wall, 4... Large diameter piston, 5... Left piston rod, 5a.・Left side small diameter piston, 6...Right side piston rod, 6a・
・・Right side small diameter piston, 7 ・Left side small diameter cylinder, 8
... Right side small diameter cylinder, 9... Left side small diameter cylinder device, 10... Right side small diameter cylinder device, 11... Left side fluid intake check valve, 12... Right side fluid intake check valve,
13...Fluid suction line, 14...Left side fluid discharge check valve, 15...Right side fluid discharge check valve, 16...
Fluid discharge line, N...flow direction control circuit

Claims (1)

[Claims] [1] Large diameter cylinder (3) and this large diameter cylinder (3)
A large diameter piston (4) that moves between its left and right ends inside the
is connected to both the left and right sides of the large diameter piston (4), and is connected to both the left and right end walls of the large diameter cylinder (3) (
A pair of left and right piston rods (3a, 3b) protrude from
a large diameter hydraulic cylinder device (2) consisting of; small diameter pistons (5a, 6a) provided at both ends of the left and right piston rods (5, 6), respectively; ) a pair of left and right small-diameter cylinder devices (9, 10) each consisting of small-diameter cylinders (7, 8) arranged on the outer periphery, and in which when the internal volume of one increases, the internal volume of the other decreases; A fluid suction line (13) and a fluid discharge line (16) are connected to the inside of each of the small diameter cylinder devices (9, 10) via a flow direction control circuit (N), and the flow direction control circuit ( N) refers to the movement of fluid from the fluid suction line (13) to the left and right small diameter cylinder devices (9, 10) and the movement of fluid from the left and right small diameter cylinder devices (9, 10) to the fluid discharge line (16). 1. A fluid supply device characterized in that the fluid supply device is configured such that movement of the fluid is possible, but movement of the fluid in the opposite direction is not possible. [2] The flow direction control circuit (N) connects the fluid suction line (13) and the left and right small diameter cylinder devices (9, 10).
) and the left and right small-diameter cylinder devices (9).
, 10) and left and right fluid discharge check valves (14, 15) respectively provided between the fluid discharge line (16) and the fluid discharge line (16). ] The fluid supply device described in the section.