JPS6393367A - Spray gun - Google Patents

Abstract

PURPOSE:To enhance the durability of a spray gun while dispensing with a packing such as rubber, by mounting a metal seal ring having ends to a nozzle valve to prevent the leakage of paint. CONSTITUTION:A seal ring is a ring having ends composed of a metal such as a gunmetal excellent in corrosion resistance to a paint solvent and the outer diameter thereof is larger than the inner diameter of the inside wall 5 of a nozzle part 4 in a non-load state. Therefore, when a nozzle valve 6 is engaged with the inside wall 5 of the nozzle part 4 after the ring 10 is mounted to the annular groove 9 provided to the nozzle valve 6, the nozzle valve 6 advances to close a nozzle orifice 2 and, at this time, said nozzle valve is positioned behind a paint inflow port 3 and the ring 10 presses the inside wall in a radius direction to develop seal effect.

Description

[Detailed description of the invention] (b) Industrial application fields The present invention relates to improvements in the nozzle portion of a spray gun.

(b) Problems to be Solved by the Prior Art and the Invention A large number of gaskets are used in spray guns to prevent paint leakage. These gaskets in conventional spray guns are made of rubber, synthetic rubber, leather, or plastic, and they have to be replaced frequently because they are corroded by paint solvents and cause paint leakage.

Especially for airless type spray guns, 10 to 20
0 to 0.1 of the paint pressurized at high pressure like 'J/ctj.
Since the painting is performed by spraying a large amount of water at a rate of 5 to 0.80 liters per minute to 8.15 to 11.0 liters per minute, the rate of damage to the gasket is extremely high, and the spray gun must be disassembled to replace the gasket during work. There are often things that need to be done.

Such work interruptions are a big time loss even for ground-based painting work, but when painting the interior space of a ship's bottom, the paint supply hose may be extended for more than 60 meters in the dark, and the spray gun must be disassembled. Therefore, the time loss required to go to the ground and return to the work place is enormous.

The necessity of replacing the gasket due to damage causes not only the above-mentioned time loss but also the cost.

To prevent such damage to the gasket or seal material, seal paint leaks without using rubber, synthetic rubber, leather, or plastic gaskets.

Alternatively, instead of the rubber, synthetic rubber, leather, or plastic described above, the material of the sealing material may be made of a metal with excellent corrosion resistance against paint solvents, such as gunmetal. The structure of the spray gun made it impossible to use this.

For example, the nozzle part of a conventional spray gun was
As shown in No. 11386, in order to prevent paint from leaking along the paint valve, a gasket is secured to the gun body and the paint valve slides through the gasket. In the case of such a structure in which the paint valve slides inside the packing, the sealing effect cannot be obtained unless the packing itself has elasticity and is configured to press against the paint valve.

As a result, materials such as rubber, synthetic rubber, leather, and plastic, which have poor corrosion resistance to paint solvents, have to be used.

An object of the present invention is to provide a spray gun that can provide a paint leakage prevention effect without using a packing having poor corrosion resistance such as rubber, synthetic rubber, leather, or plastic for the nozzle part.

(C) Means for Solving the Problems In order to achieve the above object, the spray gun of the present invention has a nozzle that moves forward and backward into the cylindrical inner wall of the nozzle part, which has a paint inlet at the rear of the nozzle opening. A nozzle valve that opens and closes the mouth is inserted, and one or more metal end seal rings are attached to the nozzle valve so that they are located behind the paint inlet when the nozzle valve moves forward and closes the nozzle mouth. It is characterized by

(iv) Example FIG. 1 shows Example 1 of the spray gun 1 of the present invention. The parts of the spray gun of the present invention that come into contact with the paint, except for the paint supply hose, are made of metal with excellent corrosion resistance.

The spray gun 1 of this embodiment 1 is an airless spray gun, and the nozzle port 2 is inserted into the cylindrical inner wall 5 of the nozzle part 4, which has a paint inlet 3 on one side of the nozzle port 2, by moving forward and backward.
A nozzle valve 6 for opening and closing is inserted.

The nozzle valve 6 consists of a cylindrical head 7 having an outer diameter equal to the inner diameter of the cylindrical inner wall 5 of the nozzle part 4 and sliding along the inner wall 5, and a rod 8 connected to the cylindrical head 7. An annular groove 9 is formed in the columnar head 7, and a metal end seal ring 10 is mounted in the annular groove 9.

This seal ring 10 is attached to the nozzle valve 6 as shown in FIG.
When the nozzle valve 6 moves forward and closes the nozzle port 2, it is located behind the paint inlet, and the paint is prevented from leaking along this regardless of the position of the nozzle valve 6.

As shown in FIG. 2, the seal ring 10 is an end ring, and a seal ring whose outer diameter is larger than the inner diameter of the inner wall 5 of the nozzle portion 4 under no load is used. Therefore, when the ring 10 is installed in the annular groove 9 and the nozzle valve is inserted into the nozzle inner wall 5, the ring 10 presses the inner wall in the radial direction, producing a sealing effect. A leaf spring may be inserted between the ring 10 and the annular groove 9 to increase the pressing force.

Although a single seal ring 10 has an excellent sealing effect, if a plurality of seal rings 10 are installed in close contact with each other or separated from each other while shifting the end portions 10a (seams), the sealing effect becomes even more excellent.

A suitable material for the seal ring 10 is a metal having excellent corrosion resistance against paint solvents, such as gunmetal.

As shown in the figure, the front end 11 of the cylindrical head 7 is formed into a tapered shape so as to correspond to the shape of the inner wall tip of the nozzle part 4. When the nozzle valve 6 moves forward, the front end 11 of the front end 11 tapers. closes the nozzle port 2 and stops spraying the paint.

Reference numeral 12 denotes an annular groove for evenly spreading the inflowing paint over the inner wall of the nozzle portion 4.

Reference numeral 13 denotes a cylindrical member for forming the internal space of the nozzle portion 4, which has a screw formed on its outer peripheral surface and is attached to the spray gun body 14. The end portion 15 of this cylindrical member 13 is formed into a tapered shape so that the nozzle valve 6 with the seal ring 10 attached thereto can be easily attached thereto.

16 is a washer, 17 is a spray tip, 18 is a tip 17
A cap for attaching the washer 16 to the spray gun has a screw formed on its inner wall.

A coil spring 21 surrounds the rod 8 of the nozzle valve 6 and is interposed between the rear end wall 19 of the cylindrical head 7 of the nozzle valve 6 and the bottom wall 20 connected to the cylindrical inner wall 5 of the nozzle part. equipped. When the rod 8 pulls the trigger 22, the nozzle valve 6 moves back while compressing the spring 21, opening the nozzle port 2, and the trigger 22
The nozzle valve 6 is attached to the trigger 22 so that when released, the nozzle valve 6 moves forward due to the restoring force of the spring 21 and closes the nozzle opening 2.

24 is an engagement groove at the end of the rod 8.

A paint passage 25 communicates with the hose 26 via a joint 27 between the gun body 14 and the paint supply hose 26.

Next, the connecting portion 27 between the gun body 14 and the paint supply hose 26 is
As shown in the figure, is a tapered joint that is rotatably and elastically pressed.

That is, the connecting member 32 has a first tapered surface 2B formed at the end of the gun body 14, a second tapered surface 29 having a shape corresponding to the first tapered surface 28, and a first receiving portion 31 of the coil spring 30. is connected to the hose 26 using a cap nut 33, the second receiver of the coil spring 30 surrounds the supporting member 35 having a section 34, the first receiver surrounds the connecting member 32 between the section 31 and the second receiver 34. The first tapered surface 2 is screwed onto the end portion 36 of the gun body while interposing the coil spring 30.
8 and the second tapered surface 29 are elastically pressed together.

In the first embodiment shown in FIG. 1, the second tapered surface 29 is a truncated conical tapered surface, and the first tapered surface 28 is formed in a shape corresponding to this, but in the second embodiment shown in FIG. The first tapered surface 78 is a truncated conical tapered surface, and the second tapered surface 79 is formed in a shape corresponding to this.

As described above, in the spray gun 1 of the present invention, the joint 27 between the gun body 14 and the paint supply hose 26 is a tapered joint that is rotatably and resiliently pressed, so that the gun body 14 can rotate smoothly. To prevent a hose from twisting and to prevent paint leakage without using a gasket that is easily corroded by paint solvents, such as gaskets made of rubber, synthetic rubber, leather, or plastic.

Furthermore, when paint stuck to the joints of a spray gun, it was soaked in a solvent to dissolve it, but with conventional spray guns, the seals were corroded by the solvent, but the joints of the spray gun of the present invention Since it is made only of corrosion-resistant metals, it will not be corroded by solvents and can easily remove stuck solvents.

In addition, the pressure contact force on the tapered surface can be determined by the degree of tightening of the support member,
Alternatively, it can be adjusted by using springs with different elasticities.

In the first embodiment shown in FIG. 1, the length of the second tapered surface 29 of the connecting member 32 is set longer than the length of the first tapered surface 28, so that even if the first tapered surface 28 wears out and retreats, It is formed so that the paint leakage prevention effect can be maintained by pushing in the two-tapered surface 29. Therefore, in preparation for the above-described pushing of the second tapered surface 29, a gap 37 is provided between the support member 35 and the gun body.

Furthermore, in order to prevent paint leakage, the larger the contact area between the first tapered surface 2B and the second tapered surface 29, the more effective it is. good.

As shown in the figure, the rear end of the support member 35 extends in a cylindrical shape and serves as a guide 38 to prevent the hose 26 from bending. Due to the presence of this guide 38, even if the hose 26 bends, the tapered joint will not be connected. It is designed so that large loads are not applied to it.

FIG. 4 shows a spray gun 41 according to a third embodiment of the present invention, which differs from the first embodiment shown in FIG. 1 in the mechanism for advancing and retracting a nozzle valve 46 to open and close a nozzle opening 42. still,
Two metal end seal rings 50, 50 are attached to the cylindrical head 47 of the nozzle valve 46 of this second embodiment, and the cap, tip, and cylindrical member shown in FIG. It is formed of a member 49.

That is, in the spray gun 41 of the third embodiment, the nozzle valve 46
A male threaded portion 60 is formed on the rod 48 and is screwed together with a female threaded portion (not shown in the figure) of the gun body.
A configuration is adopted in which the nozzle valve 46 is moved forward and backward by rotating and reversely rotating the nozzle opening 42 by a driving means to open and close the nozzle port 42.

Specifically, this driving means includes a pin 61 protruding from a male threaded portion 60, a cam plate 63 having an oblique cam groove 62 in which the tip of the pin is slidably fitted, and one end of which is pivoted to the cam plate 63. The trigger 64 consists of a rod 65 which is attached to the gun body 54 and has its other end attached to the trigger 64, and a coil spring 66 which has one end fixed to the gun body 54 and the other end fixed to the pin 61.
When pulled, the cam plate 63 retreats via the rod 65, causing the pin 61 to rotate along the cam groove 62 to the position indicated by the two-dot chain line in FIG. Then, when the nozzle valve 46 is retreated and the trigger 64 is released, the pin 61 rotates in the opposite direction due to the restoring force of the coil spring 66, causing the male threaded portion 60 to rotate in the opposite direction and tighten. , so that the nozzle valve 46 can be moved forward. 67 is screw 68.6
8 is a support cover for the cam plate 63 fixed to the gun body 54. The nozzle valve 46 moves forward, and the nozzle valve 4
A spring 6 is always attached to the pin 61 so that the tip of the pin 6 can close the nozzle opening 42 while pressing it to prevent paint from leaking.
It is preferable to form the structure so that a load is applied by 6.

Further, in order to increase the amount of advance of the male screw portion 60 during rotation, it is preferable to make the screw multi-thread.

(f) Effects As mentioned above, the spray gun of the present invention is equipped with a metal end seal ring on the nozzle valve to prevent paint from leaking. It is no longer necessary to use synthetic rubber, leather, or plastic gaskets that have poor corrosion resistance against paint solvents, dramatically improving the durability of the spray gun, and reducing time lost when replacing sealants. Economic losses can be significantly reduced. Moreover, the structure of this nozzle part is extremely simple and its manufacture is also easy.

Furthermore, in addition to the above, if the connecting part between the gun body and the paint supply hose is made into a tapered structure that is rotatably and elastically pressed as in the embodiment shown in the drawings, this part can also be coated with rubber, synthetic rubber, etc. Leather and plastic gaskets are no longer required,
There is no need to use packing that has poor corrosion resistance against paint solvents. Furthermore, when removing the solvent stuck to the spray gun, there is no need to consider damage to the gasket, and the stuck paint can be easily removed.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a spray gun according to a first embodiment of the present invention, Fig. 2 is a perspective view of a metal end seal ring, and Fig. 3 is a sectional view of essential parts of a spray gun according to a second embodiment of the present invention. , FIG. 4 is a cross-sectional view of the main parts of the spray gun according to the third embodiment of the present invention, and FIG.
The figure shows a sectional view taken along the line V-V in FIG. 4, and FIG. 6 shows a cam plate used in the spray gun of Example 3. 1.41...Spray gun, 2.42.
......Nozzle opening, 3...Paint inlet, 4...Nozzle part, 5...
......Cylindrical inner wall, 6,46...Nozzle valve, 7.47...Cylindrical head, 8,
48・・・・・・・・・Rod, 9・・・・・・・・・
Annular groove, 10.50...Seal ring,
19・・・・・・・・・Rear end wall, 20・・・・・・・・・
・Bottom wall, 21... Coil spring, 22.6
4......Trigger, 60...Male thread, 61...Pin, 62...
...Cam groove, 63...Cam plate, 65...Rod, 66...
...Coil spring. Patent applicant: Tabe Goto Agent: Patent attorney (8070) Hajime Imamura Figure 3

Claims (5)

[Claims] (1) A nozzle valve that opens and closes the nozzle opening by moving forward and backward is inserted into the cylindrical inner wall of the nozzle part, which has a paint inlet at the rear of the nozzle opening. One or more spray guns attached to a nozzle valve so that they are located behind the paint inlet when the nozzle opening is closed. (2) The nozzle valve includes a cylindrical head having an outer diameter equal to the inner diameter of the cylindrical inner wall of the nozzle portion and sliding along the inner wall, and a rod connected to the cylindrical head, and the seal ring is connected to the cylindrical head. , a spray gun according to claim 1, which is mounted in an annular groove formed in a cylindrical head. (3) A coil spring is interposed between the rear end wall of the cylindrical head of the nozzle valve and a bottom wall connected to the cylindrical inner wall of the nozzle part, surrounding the rod of the nozzle valve, and the rod is The patent claim is attached to the trigger so that when the trigger is pulled, the nozzle valve moves back while compressing the spring and opens the nozzle opening, and when the trigger is released, the nozzle valve moves forward due to the restoring force of the spring and closes the nozzle opening. The spray gun according to range (2). (4) A male thread is formed on the rod of the nozzle valve and screwed together with a female thread on the gun body, and the male thread of the rod is rotated and reversed by a driving means to move the nozzle valve forward and backward. A spray gun according to claim (2) comprising: (5) The driving means includes a pin protruding from the male screw portion, a cam plate having an oblique cam groove in which the tip of the pin is slidably fitted, one end of which is pivotally connected to the cam plate, and the other end of which is a trigger. It consists of a rod attached to the gun body and a coil spring with one end fixed to the gun body and the other end fixed to the pin. When the trigger is pulled, the pin moves along the cam groove as the cam plate retreats via the rod. When the nozzle valve is retracted and the trigger is released, the pin rotates in the opposite direction due to the restoring force of the coil spring, causing the male thread to rotate in the opposite direction. The spray gun according to claim 4, wherein the nozzle valve is moved forward by.