The invention relates to a paint spray gun according to the preamble of Claim 1 and an associated compressed air distribution insert according to the preamble of Claim 18.
The generic paint spray gun is known from EP 0 706 832 B1. Said paint spray gun presents a compressed air distributor which is connected to a compressed air feed line, and which distributes the compressed air of the compressed air feed line over a horn air supply line and a round jet supply line. The compressed air quantity fed to the horn air supply line can be set by screw adjustment of a plug, which presents a terminal sealing spigot for continuous opening or closing of the horn air supply line. To delimit the pressure that is generated in the round jet area to a maximum, if at the time of the closing of the horn air the pressure in the round jet area increases above the maximum admissible for paint spray guns, the plug presents, seen from its end, an area of larger diameter, in the direction towards the sealing spigot, which also continuously narrows the air pathway between the compressed air feed line and round jet supply line, at the time of the closing of the horn air supply line. The plug is shifted there by means of a knurled knob rotating in the axial direction. The solution described therein presents the disadvantage that, owing to the axial resetting kinematics of the plug for opening or closing the lines in the compressed air distributor, the knurled knob needs to be turned one rotation. Moreover, the design of the plug with the sealing spigots and the plate-like disk makes it impossible to determine or calculate with precision the distribution of air in the compressed air distributor. In addition, the multipart design is disadvantageous here from the point of view of manufacturing technology. Moreover, during the adjustment, the distance between the knurled knob and the gun body changes, which is often perceived as disadvantageous.
The invention is consequently based on the problem of providing a paint spray gun and a compressed air distributor that overcome the above-mentioned disadvantages, and that allow a setting of the pressure, which is simple to perform, as well as an easily calculated compressed air distribution in the paint spray gun.
This problem is solved by a paint spray gun having the characteristics of Claim 1, as well as by a compressed air distribution insert having the characteristics of Claim 18. Advantageous embodiments and preferred embodiments of the invention can be taken from the dependent claims.
A paint spray gun mentioned in the introduction is characterized according to the invention by the fact that the setting element is designed as a rotary distributor for opening and closing the openings of the round jet line and the wide jet line, which is immovable in the axial direction of the axis of rotation in the rotary distributor, which is held in the compressed-air distribution chamber, and which can be rotated about the axis of rotation. Due to this exclusive adjustment kinematics of the rotary distributor, the clearly smaller adjustment angle from completely closed to completely wide jet opening kinematics is made possible here. In the solution according to EP 0 706 832 B1, the adjustment angle, on the other hand, is approximately 410°; in this case, the knurling knob therefore has to be turned from the opened to the closed horn air opening by more than one full rotation. This prevents, among other factors, a simple display of the current opening position indicator of the horn air opening. Moreover, the design of the rotary distributor, and thus the setting of the correct ratio of the different openings in the compressed air distribution chamber relative to each other can be simulated, calculated, or determined empirically, in a simple way. An additional advantage is that the handle for the rotary distributor is always at the same distance from the paint spray gun.
In a preferred embodiment of the invention, the compressed air distribution chamber is designed as a compressed air distribution cylinder having an opening, and walls formed by the bottom and a lateral surface, wherein the rotary distributor presents, at its end turned away from and/or facing the rotary handle, a guide that is applied to the lateral surface. As a result, a simple design can be achieved that at the same time provides good guidance of the rotary distributor in the compressed air distribution cylinder. In a manner that is advantageous for the manufacturing technology, the guide can be a circular disk and/or a circular ring having an outer diameter adapted to the inner diameter of the compressed air distribution cylinder.
It is preferred to form the rotary distributor so that it passes by a lateral surface section of a cylinder about the axis of rotation, which rotary distributor slides with rotation and, conclusively, along the lateral surfaces of the compressed air distribution cylinder.
The round jet opening, the wide jet opening, and/or the compressed air feed line opening can preferably open into the lateral surface of the compressed air distribution cylinder, and the round jet setting area, the wide jet setting area, or the compressed air feed line setting area can be rotated along the lateral surface of the compressed air distribution cylinder. Alternatively or additionally, the round jet opening, the wide jet opening, and/or the compressed air feed line opening can also open in the bottom of the compressed air distribution cylinder, wherein the respective setting area can then be provided.
In order to enable a simple display of the rotary distributor setting in the compressed air distribution chamber, a setting display can be provided on the rotary handle for displaying the setting of the rotary distributor in the compressed air distribution chamber.
A compressed air distribution insert mentioned in the introduction is characterized according to the invention by the fact that, on an end of the distribution spindle, which can be inserted into the compressed air distribution chamber, a rotary distributor can be provided, which is not movable with respect to the rotary handle in the axial direction of the axis of rotation, and which is rotatable about the axis of rotation.
Additional features and advantages of the invention result from the following description of a preferred embodiment example in reference to the accompanying drawings. The drawings show:
a) round jet line with detail Z;
b) wide jet line with detail Y;
a) a front top view on the knurled knob of the compressed air distributor;
b) a side top view of the compressed air distributor of
c) a section through the compressed air distributor of
d) a section through the compressed air distributor of
e) a section through the compressed air distributor of
a shows a section through a paint spray gun 1 with a handle 2 and a paint nozzle head 3. The paint nozzle head 3 presents a central round jet nozzle 4 as well as two wide jet nozzles 5 arranged on horns. The round jet nozzle 4 is supplied via a round jet line 6 shown in
The compressed air distribution cylinder 8 is exposed to compressed air via a compressed air feed line opening 10′ of a compressed air feed line 10 and via a valve device 11, which in itself is known, from the compressed air feed 12. The valve device 11 is operated in a known manner by means of a drain-off 11a, so that, via the compressed air feed 12, from a not-shown compressed air source, for example, a compressor, compressed air can be introduced into the compressed air distribution cylinder 8.
In
The paint spray gun 1 according to the invention differs from the usual paint spray guns primarily by the compressed air distributor 9 according to the invention, which is described in detail in reference to
In order to be able to set the compressed air distribution in the compressed air distribution cylinder 8, as well as the pressure in the round jet line 6 and wide jet line 7, a radially adjustable distribution spindle 13 with a rotary distributor 14, as shown in
The distribution spindle 13 and thus the rotary distributor 14 can be turned by means of a rotary handle designed as a knurled knob 15, which functions as handle, radially about the axis of rotation D in the compressed air distribution cylinder 8. The knurled knob 15 can be turned clockwise from the position shown in
The knurled knob 15 is here always at the same distance 22 from the piston body 1. The distance is selected in such a manner that a penetration of overspray or the like to the distribution spindle 13 cannot occur. In the embodiment example, it is approximately 1.2 mm. The design according to the invention thus has a high operational reliability. In addition, possible irritation due to a handle being in a high position are avoided.
In
The rotary distributor 14 presents, at its lower end in
In the present embodiment example, the rotary distributor 14 is designed in two parts. In its area 25, shown at the top in
Naturally, manufacturing the rotary distributor 14, as a single part or as several parts, from any other material or any other plastic or any other desired material combination is also possible.
At its top end, the distribution spindle 13 is rotatably mounted by means of a threaded sleeve 18 in the compressed air distribution cylinder 8, so that the rotary distributor 14, although being rotatable in the compressed air distribution cylinder 8 about the axis of rotation D, is not shiftable in the axial direction of the axis of rotation D in the compressed air distribution cylinder 8. The threaded sleeve 18 for this purpose is screwed by means of an outer threading into a corresponding inner threading at the outer end of the compressed air distribution cylinder 8. The circular area of the cover plate 17, which is turned away from the rotary distributor 14, serves as an abutment for a front side of the threaded sleeve 18, which faces the compressed air distribution cylinder 8. The threaded sleeve 18 thus ensures a secure seat of the distribution spindle 13, and consequently of the rotary distributor in the compressed air distribution cylinder 8, and, in collaboration with a gasket seal 23 having an annular design here, in addition to the cover plate 17, it seals the inner space of the compressed air distribution cylinder 8 against air flowing outwards.
In addition, the threaded sleeve 18 is sealed with respect to the gun body 1.
The knurled knob 15 is rotatably connected via a threaded screw 19 shown in
The inner collar 24 on the knurled knob 15 works in collaboration with the abutments 21 on the piston body 1. In the present embodiment example, in each case one abutment 21 is provided on the opening position, as well as on the closed position. In the present embodiment example, the two positions enclose an angle of 95°. As a result, the adjustment can be visually perceived very well.
In other conceivable embodiments, larger angles, for example, 90°-180°, but preferably always smaller than 360°, can be provided.
As can be seen in
Alternatively, instead of the notch, an imprinted single marking or a scale, for example, can be provided as setting display 20. Obviously, the setting display 20 could be provided on the gun body 1 instead of the knurled knob 15.
In the variant of the knurled knob 15 shown in
The construction of the distribution spindle 13 and of the rotary distributor 14 is now explained in reference to
In contrast to the above, a round jet setting area 147 is located above the wide jet setting area 146 and in the vicinity of the cover plate 17, since the round jet line 6 opens into the upper area of the compressed air distribution cylinder 8. Since the round jet line opening 6′ is also slightly offset in the peripheral direction of the compressed air distribution cylinder 8 towards the wide jet line opening 7′, the wide jet setting area 147 is additionally offset accordingly in the peripheral direction with respect to the wide jet setting area 146. The wide jet setting area 147 presents an approximately rectangular round jet setting opening 147a, in the present embodiment example, which is offset with respect to the wide jet closing area 146a in such a manner that, when the wide jet line 7 is completely closed, and simultaneously the compressed air feed line 10 is completely opened, the permissible maximum pressure in the round jet line 6 and thus on the round jet nozzle 4 is not exceeded.
Obviously, the round jet setting area 147 can also be designed as an elongated hole or the like.
The left margin of the rotary distributor 14, in
In the state shown in
To reduce the feed of compressed air to the wide jet nozzle 5, and thus reduce the pressure on the wide jet line opening 7′ in the compressed air distribution cylinder 8, the knurled knob 15 is turned from the position shown in
If the knurled knob 15 and thus the rotary distributor 14 is then turned by an additional approximately 45° clockwise from the position shown in
Alternatively, the round jet line opening 6′ could be completely closed, by selecting an appropriate geometric shape of the round jet setting opening 147a.
In addition, depending on the shape of the wide jet opening area 146b, either an exponential, or a linear, or a degressive closure characteristic can be achieved.
The fact that, in the embodiment of the rotary distributor 14 according to the invention, the opening 10′ of the compressed air feed line 10 can close, is the result of the above described constructive design of the rotary distributor 14, which is adapted congruently to the surfaces of the compressed air feed line 10. In alternative embodiments without such adaptation, the compressed air feed line 10 is accordingly not [closed] or not completely closed. There is no risk of large negative consequences for the desired function of the paint spray gun pistol. In any case, according to the invention, the possibility exists to feed the entire air quantity or reduced air quantity to the rotary distributor 14, as desired.
An essential advantage compared to the solutions known from the state of the art is that, in the present invention, the radial adjustment kinematics of the rotary distributor 14 allow a considerably smaller adjustment angle. In the solution according to EP 0 706 832 B1, the adjustment angle is, for example, approximately 410°, the knurled knob thus has to be turned there from the opened to the closed horn air opening, by more than one full rotation. This prevents, among other factors, a simple setting display of the current opening of the horn air opening. In addition, with the plug in the sealing spigot of EP 0 706 832 B1, setting of the correct ratio of the different openings in the compressed air distributor with respect to each other is exceedingly difficult, and a corresponding simulation or calculation is possible only at great expenditure. Here too, a linear adjustment kinematics is not possible, and the knurling knob changes its distance from the body. If it is in an undesirable high position, it is possible, under some circumstances, to introduce overspray into the gun, which is not the case in the solution according to the invention.
An additional advantage of the invention is that single-handed operation of the rotary distributor 14 is possible without a problem.
In an alternative design of the distribution spindle 13, the rotary distributor can also be designed differently. For example, as rotary distributor, a hollow cylinder can be used whose lateral surface halves, divided in the axial direction, present symmetric, mutually transitioning round jet, wide jet and compressed air feed line setting areas. As a result, the hollow cylinder could be turned with a rotation of 180° from the completely opened into the completely closed position of the wide jet line opening 7′, wherein, due to the subsequent further rotation in the same direction, the wide jet line opening 7′ could then be opened again in a corresponding manner. Instead of a division into halves, the hollow cylinder can also be divided into quarters, which again present corresponding symmetric and mutually transitioning round jet, wide jet, and compressed air feed line setting areas. Then, by means of a rotation of 90°, one can alternate between the opened and closed position of the wide jet line opening 7′, namely a total of four times within one full rotation of the hollow cylinder. Said alternatives present the advantage that no abutments are needed to prevent overrotation of the distributor spindle in any direction. If the round jet, wide jet, and compressed air feed line setting areas in the alternatives are mutually transitioning, but not mutually symmetrical in design, then different characteristics of the compressed air distribution could be enabled between the opened and closed position of the wide jet line opening.
In an additional alternative, instead of the rotary distributor 14, a solid cylinder can also be used, which presents an inlet opening that serves to partially open or close the compressed air feed line 10, wherein, from this inlet opening, two channels then branch off in the solid cylinder to the wide jet line opening 7′ or the round jet line opening 6′. The channels then present, at their other end, openings in the solid cylinder which are designed in such a manner in reference to the wide jet line opening 7′ or round jet line opening 6′, that, when the wide jet line opening 7′ is completely closed, the allowed maximum pressure still is applied on the round jet line opening 6′. Similarly, all the openings in the solid cylinder are designed in such a manner that, during the closing process, the maximum pressure is exceeded at no point at or in the round jet line 6 or the wide jet line 7.
In an additional embodiment, the round jet line opening 6′, the wide jet line opening 7′ or the compressed air feed line opening 10′ or also several of these openings can open at the bottom of the compressed air distribution cylinder 8. To be able to close or open said openings arranged in the bottom, the corresponding setting area then has to be provided with opening and closing areas in the bottom disk 16 of the distribution spindle 13. For example, if the wide jet line opening is in an eccentric position in the bottom of the compressed air distribution cylinder 8, that is outside of its central longitudinal axis, then it would be advantageous if, in the bottom disk 16, a wide jet line opening adapted to the size of the wide jet line opening would narrow in a spiral pattern to a wide jet closing area without opening.
In an additional embodiment, the compressed air distribution chamber can present, instead of a continuous compressed air distribution cylinder 8 with one diameter, preferably also mutually axially arranged cylinder bores of different diameter, where the diameter preferably decreases stepwise from the opening of the compressed air distribution chamber to the bottom. The distributor device is then advantageously adapted to the change in diameter. Instead of a step-shaped change in the diameter of the compressed air distribution chamber, the compressed air distribution chamber can also be designed advantageously in a conical shape or present a conical area, wherein the distributor device is then also adapted advantageously to this shape of the compressed air distribution chamber.
In order to make the advantages of the invention available for an already existing paint spray gun, the compressed air distribution insert can be formed from the distribution spindle 13 with the rotary distributor 14, the threading sheath 18, the knurled knob 15, and the threaded screw 19. Said compressed air distribution insert can then be inserted in the compressed air distribution chamber of the existing paint spray gun. Here, the shape of the compressed air distribution chamber can be taken into account advantageously in the design and modeling of the rotary distributor. Similarly, the other components of the compressed air distribution insert are adapted to the circumstances of the existing paint spray gun. Due to the simple design of the rotary distributor, the determination of its shape and the resulting compressed air distribution in the compressed air distribution chamber can be determined in a simple manner from the shape of the existing compressed air distribution chamber. The additional advantages and designs of the individual components of the compressed air distribution insert, which are indicated extensively above in the description of the pain spray gun according to the invention, naturally also apply to the compressed air distributor inset itself. Instead of the knurled knob, any other suitable rotating handle can be attached to the distribution spindle.
Other alternative embodiments, in which the mouths of the round jet line 6, of the wide jet line 7, as well as of the compressed air feed line 10 into the compressed air distribution cylinder 8 can be adjusted exclusively by turning about the axis of rotation D, without actual shift of rotary distributors, perforated aperture plates, etc., are also within the scope of the present invention.
Number | Date | Country | Kind |
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10 2009 032 399.6 | Jul 2009 | DE | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/EP2010/003399 | 6/7/2010 | WO | 00 | 12/27/2011 |