JP2008018296A - Air spray gun - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an air spray gun comprised of an easily attachable/detachable paint nozzle that can be mounted onto the front end of a gun main body in one-touch by using no tools. <P>SOLUTION: The air spray gun is constituted of a gun main body, a paint nozzle 5 equipped with a paint ejection port 4A, and an air cap 8 which is mountable to the gun main body by screwing and equipped with an air ejection port 7A. The paint nozzle 5 and the gun main body are equipped with a locking means 30 comprised of a protrusion 31 protruding in the radial direction formed in either of the paint nozzle 5 and the gun main body and a locking member 32 comprising a notched part 32A through which the protrusion 31 passes formed in the other of the paint nozzle 5 and the gun main body and a circumferential locking face 32B for locking the protrusion 31 having been caused to pass through the notched part 32A by its rotation around the axis of the paint nozzle 5. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an air spray gun that facilitates attachment and removal of a paint nozzle.

  For example, when repairing the surface of an automobile, a paint putty such as a polyester putty may be applied using a spray gun as a base treatment. However, since this paint putty is a so-called mixed paint in which a main agent is mixed with a curing agent, the curing start time is as fast as 15 to 60 minutes. Therefore, in order to prevent clogging of the paint discharge port in the spray gun, it is necessary to remove the paint nozzle from the spray gun and frequently wash the paint flow path in the paint nozzle.

  However, in the conventional spray gun, as shown in FIGS. 6 and 7, a hexagonal bolt-shaped head a1 is formed on the front end side of the paint nozzle a, and an external screw part a2 is formed on the rear end side. In the recess b1 provided at the front end of the gun body b, a special tool such as a spanner was used for screwing. Therefore, the installation and removal work of the paint nozzle a is inconvenient. In addition, there is a problem that part of the paint in the paint flow path sometimes enters the screwed portion and makes it difficult to remove the screw. Although the air cap c covering the paint nozzle a is also screwed to the front end of the gun body b via the nut ring c1, this can be easily removed with bare hands without using a dedicated tool. It is not particularly a problem.

  Accordingly, the present invention provides an air spray gun which can be used for spraying a mixed paint such as a paint putty, which can be easily attached and detached, with the paint nozzle being able to be locked to the front end of the gun body with one touch. It is aimed.

Japanese Patent Laid-Open No. 62-148365

In order to achieve the above object, the invention of claim 1 of the present application includes a gun main body, a paint nozzle having a paint flow passage having a paint discharge port opened and closed by a needle valve, and screwed into the gun main body. An air cap formed with an air flow path having an air outlet,
The paint nozzle and the gun body have a radial projection formed on one of them, and a cutout portion provided on the other side through which the projection passes and the projection passing through the cutout engages the projection with its rotation. Comprising a locking means comprising a locking portion having a circumferential locking surface to perform,
In addition, the paint nozzle is pressed against the gun body and attached by screwing the air cap.

  According to a second aspect of the present invention, an elastic seal ring is interposed between the paint nozzle and the gun body at a portion where the paint nozzle is pressed against the gun body, and the protrusion and the locking surface are connected to the seal ring. It is characterized by being pressed by the elastic force of.

  According to a third aspect of the present invention, the seal ring is detachably attached to the gun body.

  According to a fourth aspect of the present invention, the projection is formed on the paint nozzle, and the locking portion is provided on the gun body.

In the invention of claim 5, the gun body comprises a paint nozzle mounting recess that is recessed in the front end on the discharge port side,
And the paint nozzle is mounted concentrically with the paint discharge port facing forward in the paint nozzle mounting recess,
The seal ring is held by a groove-like portion provided at the rear end of the paint nozzle mounting recess,
The air cap is screwed to the front end of the gun body, and forms an annular air outlet that surrounds the paint outlet in cooperation with the paint nozzle;
In addition, the paint nozzle is formed in a central portion of the paint nozzle with a maximum diameter portion projecting from the protrusion formed of a plurality of locking pins and having a tubular shape having a center hole,
In addition, on the front end side of the paint nozzle mounting recess of the gun body, a notch formed by a groove through which the locking pin passes, and a locking pin that has passed through the notch are engaged by rotation thereof, so that the locking pin is The locking portion is formed of a circumferential locking surface that prevents the locking.

  As described above, in the present invention, a radial protrusion is formed on one of the paint nozzle and the gun body, and on the other side, a notch through which the protrusion passes and a protrusion that passes through the notch are associated with its rotation. Since the locking portion having the locking surface to be stopped is formed, the paint nozzle is inserted into, for example, the paint nozzle mounting recess provided in the gun body, and twisted in the rotation direction to Can be locked with one touch. Therefore, it is possible to easily attach and remove the paint nozzle to / from the gun body without using a dedicated tool. For example, when performing spraying of mixed paint, the work of cleaning the paint nozzle is reduced. Can be reduced.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. 1 is a cross-sectional view of an air spray gun according to the present invention, FIG. 2 is an enlarged cross-sectional view of the main part thereof, and FIG. 3 is an exploded perspective view thereof.

  In FIG. 1, an air play gun 1 according to this embodiment includes a gun body 2, a paint nozzle 5 having a paint flow path 4 having a paint discharge port 4A, and an air flow path 7 having an air discharge port 7A. An air cap 8 is provided, and the paint discharged from the paint discharge port 4A is sprayed in the form of atomization by the compressed air from the air discharge port 7A.

  In this example, the case where the paint is a two-component mixed paint in which a main agent is mixed with a curing agent such as an epoxy resin paint, a polyester resin paint, and a polyurethane resin paint is illustrated. In this mixed-type paint, since the curing start time is as fast as 15 to 60 minutes, for example, it is required to remove the paint nozzle 5 and frequently wash the paint flow path 4 in order to prevent clogging of the paint discharge port 4A. Is done. Therefore, the air play gun 1 of the present invention in which the paint nozzle 5 is attached to and detached from the gun body 2 with one touch can be suitably employed.

  In this example, the gun body 2 can be provided with a handle 2B on the rear end side of the body portion 2A extending forward and backward, and the paint nozzle 5 and the air flow path 7 can be detachably mounted on the front end side. It has a pistol shape with a front end 2C. In this gun body 2, an air introduction path that guides compressed air flowing from an air intake 21 provided at the lower end of the grip portion 2 B to the air flow path 7 of the air cap 8 through the inside of the gun body 2. 22 is formed. Note that an air valve 24 having a known structure for opening and closing the air introduction path 22 by operating a trigger 23 is interposed in the handle portion 2B.

  As shown in FIGS. 2 and 3, the front end 2C of the gun body 2 is provided with a coating nozzle mounting recess 25 that opens at the front end surface 2S and extends rearward, and the front end 2C. An outer screw portion 27 into which the air cap 8 is screwed is formed on the outer periphery of 2C. A paint introduction passage 26 is connected to the rear end portion of the paint nozzle mounting recess 25 through a step, and the rear end portion of the paint introduction passage 26 pivots on a needle valve 20 concentric with the paint passage 4. It is closed by a sealing cap 28 that is inserted in a sealed state. The paint introduction path 26 is connected to a paint intake port 29 provided at the front end 2C.

  In the present invention, the paint nozzle 5 is locked to the paint nozzle mounting recess 25 via the locking means 30 with one touch. Then, the locked paint nozzle 5 is pressed against the gun body 2 by subsequent screwing of the air cap 8 and is fixed without causing displacement or detachment.

  Here, the locking means 30 includes a radial protrusion 31 formed on one of the paint nozzle 5 or the gun body 2, a notch 32A provided on the other and passing through the notch 32A, and passing through the notch 32A. The protrusion 31 is constituted by a locking portion 32 having a circumferential locking surface 32B that locks the protrusion 31 along with its rotation. At this time, in this example, a seal ring 33 such as an O-ring made of a rubber elastic material is attached to the rear end portion of the paint nozzle mounting recess 25 and is interposed between the paint nozzle 5 and the gun body 2. By this, the infiltration of the paint during this period is prevented. The seal ring 33 can stably press the protrusion 31 and the locking surface 32B to each other by its elastic force. Thus, while the air cap 8 is screwed, the locked paint nozzle 5 can be prevented from coming off or displaced from the coating nozzle mounting recess 25, and the locked state can be maintained reliably and stably.

  Specifically, in the present example, the paint nozzle mounting recess 25 has a first diameter portion 25A, a second diameter portion 25B, and a third diameter that are successively connected in a stepped shape from the front end side toward the rear end side. A diameter portion 25C is provided. Among these, on the inner peripheral surface of the third diameter portion 25C, as shown in FIG. 4, a groove-shaped portion 34 that detachably holds the seal ring 33 is formed. The groove portion 34 is a circumferential groove having a substantially semicircular arc shape in cross section, and can fit and hold a part of the outer periphery of the seal ring 33.

  Further, a first circumferential groove 35 extending in the circumferential direction is formed in the first diameter portion 25A at a position reserved on the inner circumferential surface and rearward from the front end. An opening 22 </ b> A that conducts to the air introduction path 22 via the air regulating valve 36 is provided on the side surface of the rear end side groove of the first circumferential groove 35. The second diameter portion 25B is formed with a second circumferential groove 37 extending in the circumferential direction at a position reserved on the inner circumferential surface and rearward from the front end. The second circumferential groove 37 is directly connected to the air introduction path 22 without the air regulating valve 36 interposed therebetween.

  Next, the paint nozzle 5 has a tubular nozzle base 38 having a center hole, and the paint channel 4 is formed by the center hole. The paint channel 4 has a large-diameter channel body 4B whose rear end is connected to the paint introduction channel 26, and a small-diameter paint discharge port 4A is provided at the front end via a tapered cone-shaped constricted portion 4C. It is open. Then, when the throttle portion 4C and the needle valve 20 come in contact with each other, the paint discharge port 4A opens and closes. The needle valve 20 has a well-known structure and operates in synchronism with the air valve 24 by the pulling operation of the trigger 23.

  The nozzle base 38 is provided with a maximum diameter portion 5A in which a knurling is engraved on the outer peripheral surface at the central portion in the longitudinal direction, and a step is formed on the rear end side of the maximum diameter portion 5A in this example. The 1st-4th small diameter part 5B1-5B4 which becomes a small diameter sequentially is provided continuously.

  The maximum diameter portion 5A is provided with a plurality of (four in this example) locking pins 39 constituting the protrusion 31 projecting radially outward on the outer periphery thereof. The annular rib portion 40 between the front end surface 2S of the gun main example 2 and the first circumferential groove 35 is formed with a notch 32A formed by a groove through which the locking pin 39 passes, and the annular ring portion 40A. The locking pin 39 that has passed through the notch 32A is engaged by its rotation by the rear end surface of the rib portion 40, that is, the groove side surface on the front side of the first circumferential groove 35, and the locking pin 39 is pulled out. A circumferential locking surface 32B to be stopped is formed.

  The first small-diameter portion 5B1 faces the inner peripheral surface of the second diameter portion 25B and is fitted with the inner peripheral surface, so that the paint nozzle 5 and the paint nozzle mounting recess 25 are concentric with each other. Align well. The second small diameter portion 5B2 is opposed to the inner peripheral surface of the second peripheral groove 37, and forms a void H that leads to the paint introduction path 26 between the inner peripheral surface. The fourth small diameter portion 5B3 has a taper that tapers toward the rear end, and presses the seal ring 33 between the gun body 2 and the fourth small diameter portion 5B3.

  In addition, the nozzle base 38 extends through the space between the rear end surface of the first small diameter portion 5B1 and the front end surface of the maximum diameter portion 5A, so that the compressed air from the coating material introduction passage 26 is supplied to the nozzle base 38. A guide hole 41 that feeds the void H to the front side is formed. The guide hole 41 is arranged with a phase shifted in the circumferential direction with respect to the locking pin 39.

  Next, the air cap 8 is integrally locked with the cap main body 8A having the air discharge port 7A and the cap main body 8A via a locking ring 8B, and the front end 2C of the gun main body 2 (the outer screw). Part 27) and a nut ring 8C that is screwed together.

  The cap body 8 </ b> A includes a recess 10 on the back surface that houses and covers the paint nozzle 5. A peripheral surface 10e of the recessed portion 10 is provided with a contact surface that contacts the front end surface of the maximum diameter portion 5A at a position radially outward from the guide hole 41. As a result, an air flow path 7 surrounded by the recess 10 and the paint nozzle 5 is formed on the radially inner side of the peripheral edge 10e, and the front end surface 2S of the gun body 2 is formed on the radially outer side of the peripheral edge 10e. And the pattern air flow path 11 enclosed with the inner peripheral surface of the nut ring 8C and the back surface of the cap main body 8A is formed. The air flow path 7 is directly connected to the air introduction path 22 through the guide hole 41 and the space H. The pattern air flow path 11 is connected to the air introduction path 22 through the notch 32A, the first circumferential groove 35, the opening 22A, and the air adjustment valve 36.

  The cap body 8A includes a hole portion that forms an annular air discharge port 7A surrounding the paint discharge port 4A in cooperation with the paint nozzle 5. In this example, the cap main body 8A is provided with auxiliary holes 12 on both sides of the air discharge port 7A, and a pair of corner portions 13 projecting radially outward and forward from the auxiliary holes 12 are provided. The pattern air port 14 is formed inward. The pattern air port 14 is electrically connected to the pattern air channel 11, and the air discharge port 7 A and the auxiliary hole 12 are electrically connected to the air channel 7.

  The locking ring 8B is locked to a circumferential groove-shaped locking groove 12a provided on the outer peripheral surface of the cap body 8A and a circumferential groove-shaped locking groove 12b provided on the inner peripheral surface of the nut ring 8C. . As a result, the cap body 8A and the nut ring 8C can be connected to each other in a relatively rotatable manner, and the paint nozzle 5 is elastically pressed and fixed to the gun body 2 via the seal ring 33 by the screwing of the nut ring 8C. Is done.

  As mentioned above, although especially preferable embodiment of this invention was explained in full detail, this invention is not limited to embodiment of illustration, It can deform | transform and implement in a various aspect.

It is sectional drawing which shows one Example of the air spray gun of this invention. It is an expanded sectional view which shows the principal part. FIG. It is an expanded sectional view which shows the holding | maintenance state of a seal ring. It is drawing which looked at the attachment state of a paint nozzle from the front side. It is sectional drawing which shows the attachment state of the conventional coating material nozzle. FIG.

Explanation of symbols

2 Gun body 2C Front end 4 Paint flow path 4A Paint discharge port 5 Paint nozzle 5A Maximum diameter portion 7 Air flow path 7A Air discharge port 8 Air cap 20 Needle valve 25 Paint nozzle mounting recess 30 Locking means 31 Projection 32 Locking portion 32A Notch 32B Circumferential locking surface 33 Seal ring 34 Groove 39 Lock pin

Claims (5)

From a gun body, a paint nozzle in which a paint flow path having a paint discharge port opened and closed by a needle valve is formed, and an air cap screwed into the gun main body and having an air flow path having an air discharge port Become
The paint nozzle and the gun body have a radial projection formed on one of them, and a cutout portion provided on the other side through which the projection passes and the projection passing through the cutout engages the projection with its rotation. Comprising a locking means comprising a locking portion having a circumferential locking surface to perform,
Moreover, the air spray gun is attached by pressing the paint nozzle against the gun body by the screwing of the air cap.   An elastic seal ring is interposed between the paint nozzle and the gun body at a portion where the paint nozzle is pressed against the gun body, and the protrusion and the locking surface are pressed by the elastic force of the seal ring. The air spray gun according to claim 1.   The air spray gun according to claim 1 or 2, wherein the seal ring is detachably attached to the gun body.   The air spray gun according to any one of claims 1 to 3, wherein the protrusion is formed on the paint nozzle, and the locking portion is provided on the gun body. The gun body includes a paint nozzle mounting recess that is recessed in the front end on the discharge port side,
And the paint nozzle is mounted concentrically with the paint discharge port facing forward in the paint nozzle mounting recess,
The seal ring is held by a groove-like portion provided at the rear end of the paint nozzle mounting recess,
The air cap is screwed to the front end of the gun body, and forms an annular air outlet that surrounds the paint outlet in cooperation with the paint nozzle;
In addition, the paint nozzle is formed in a central portion of the paint nozzle with a maximum diameter portion projecting from the protrusion formed of a plurality of locking pins and having a tubular shape having a center hole,
In addition, on the front end side of the paint nozzle mounting recess of the gun body, a notch formed by a groove through which the locking pin passes, and a locking pin that has passed through the notch are engaged by rotation thereof, so that the locking pin is The air spray gun according to any one of claims 1 to 4, wherein the locking portion is formed of a circumferential locking surface that prevents the locking.

Images