DE102012106084A1 - Component supply nozzle for supplying reactant component into mixing head, has housing, closure body, and biasing element biasing closure body in closing direction, and lock inhibiting movement of closure body in opening direction - Google Patents

Abstract

The nozzle (10) has a housing with a component inlet (13), and a component outlet (15). A closure body (20) is displaceable or movable between two positions in the housing. The closure body is closed in one position of the component outlet, and the closure body is released or is open in another position of the component outlet. A biasing element biases the closure body in a closing direction. A releasable lock inhibits movement of the closure body in the opening direction. Independent claims are also included for the following: (1) a mixing head system (2) a method for controlling a mixing head system (3) a method for controlling a component supply nozzle.

Description

The invention relates to a component feed nozzle according to the preamble of claim 1 and to a mixing head system according to claim 6.

Component feed nozzles for feeding reaction components into a mixing head are well known. Such nozzles typically include a housing, a component inlet, and a component outlet. In the housing is a movable closure member, usually in the form of a nozzle needle, which can close or release the component outlet or reduce the cross-section of the nozzle outlet to produce different pressures at different amounts.

An important criterion for such component feed nozzles is often that they are suitable for different flow rates. For this reason, spring-loaded nozzle needles are often used in such nozzles in order to keep the pressure as constant as possible in an amount adjustment. Such a nozzle is for example from the DE 10 2007 037 780 A1 known.

The use of such nozzles is nowadays preferably in Rezirkulationsmischköpfen in which the control piston has grooves. If the control piston of such mixing heads is in the recirculation position, the grooves provided in the control piston communicate with the component outlet of the nozzle and allow the component provided by the nozzle to be returned. On the other hand, if the control piston is in the firing position, the component passes from the nozzle into the mixing chamber of the mixing head. The introduction of the component is thus controlled by the movement of the control piston between recirculation position and firing position.

However, due to the configuration of the control piston, the transition between the recirculation position and the firing position results in a brief interruption of the component flow, since neither a flow of the component into the groove of the control piston nor a flow of the component into the mixing chamber is possible. This leads to a pressure increase in the nozzle. At this pressure increase, the spring-loaded nozzle needle reacts with an axial displacement, whereby the nozzle needle opens too far. This has the consequence that, when the control piston releases the mixing chamber, the nozzle is initially opened too wide and therefore an excessive amount of the component is supplied. In addition, the nozzle needle moves forward again by the spring force. However, since the nozzle was previously opened too far, now too little amount is entered into the mixing chamber, as long as have set in the piping and hose system again constant states.

A major disadvantage of such systems is therefore that prevail at the beginning shot no constant pressure and volume ratios, which is why the mixing ratio at the beginning of the shot is not right.

It is therefore the object of the invention to provide a component feeding nozzle and a mixing head system which overcome the above drawback.

This object is achieved by a component feed nozzle having the features of claim 1, a mixing head system according to claim 6, and by methods for controlling the mixing head system and the component feed nozzle according to claims 12 and 13. Advantageous developments are the subject of the dependent claims.

The component feed nozzle according to the invention is characterized in that the closure body is accommodated in the housing in such a way that it can be releasably fixed. This is realized by a releasable lock that can prevent movement of the closure body. This results in the great advantage that the movement of the closure body, for example a nozzle needle, can be actively prevented or at least limited. Thus, a threatening by an increase in pressure, unwanted movement of the closure body can be avoided.

It is basically sufficient if the releasable lock can prevent the movement of the closure body in at least the opening direction, thus preventing further opening of the component outlet. Thus, with a pressure increase of the component in the nozzle, the closure body is not moved further in the opening direction and thus an excessive component discharge from the component outlet is avoided.

To prevent the movement of the closure body, this can be clamped for example by an additional element. It is conceivable to provide a clamping jaw in the housing or the closure body guide, that is to say to provide a radially movable section, for example in the wall surface on which the closure body is guided. However, it is also possible to arrange the closure body such that a part of this is exposed and this exposed part can be fixed by a suitable clamping means.

However, an inhibition of the movement of the closure body is not intended to be exclusive be understood that the blocking of the movement of the closure body must be active. Rather, the case should also be encompassed in which the movement of the closure body is basically prevented, ie, without active activation of the barrier, in at least one direction and the suspension or release of this barrier is actively carried out. It is also conceivable in this context, a lock, which allows the movement of the closure means in one direction, for example, the nozzle closing direction, but automatically locks in the opposite direction. In this case, the lock can then be designed so that only by an active actuation of the lock and a movement of the closure body in the opposite direction is allowed.

It is particularly desirable if the barrier is designed such that the movement of the closure body by adhesion, such as a clamping takes place. Such a frictional connection can for example be realized in that the bearing or the guide of the closure body is temporarily narrowed at least locally. Alternatively, however, it is also possible to increase the outer circumference dimension of a part of the closure body itself, that is to say for example in the case of a nozzle needle, at least in places. For this purpose, for example, a portion of the closure body may be formed in the manner of a hydraulic mandrel.

It is advantageous if the component pressure is monitored and the barrier is actuated when the desired component pressure is reached in order to prevent further movement of the closure body in the opening direction. For this purpose, for example, a sensor can be provided which monitors the component pressure in a component supply line, at the component inlet or within the nozzle between component inlet and component outlet.

The releasable barrier may comprise a sleeve immovably arranged in the axial direction, in which the closure body is at least partially received, and a means for applying a force to the outside of the sleeve. The force can then be applied to the sleeve in such a way that its inner diameter changes in such a way that a clamping of the closure body takes place. Such means for applying a force may be any means capable of causing deformation of the sleeve.

Advantageously, the sleeve has a smaller wall thickness in at least one region and the means for applying a force is designed such that the force is applied to the sleeve in the region of lesser wall thickness. By this configuration, a defined clamping area can be created in the sleeve.

For example, the sleeve may be mounted in a cylinder bore and have a recess in its outer peripheral surface, so that between the sleeve and cylinder surface a pressure chamber is formed and may be a fluid channel which opens into the pressure chamber. This pressure chamber, a pressurized medium, such as hydraulic oil, are supplied, whereby a pressure on the outside of the sleeve can be applied to achieve a corresponding reversible deformation of the sleeve and thus a clamping of the closure body.

However, the storage or recording of the closure body does not necessarily have to be done directly through the housing or by a direct contact between the closure body and the housing. It may be advantageous if in the housing further comprises a closure body guide is provided, in which the closure body is at least partially guided. If such a closure body guide is provided, then the sleeve can be accommodated at least partially in the closure body guide. The opening into the pressure chamber fluid channel is then at least partially formed in the closure body guide, wherein the formed in the closure body guide part of the fluid channel can then also be referred to as a connecting channel. It is also possible to provide a plurality of channels at least in the closure body guide in the circumferential direction, all of which open into the pressure chamber. The closure body guide can then have in its outer circumference a circulation groove, which on the one hand communicates with these channels and on the other hand communicates with a part of the fluid channel formed in the housing. Thus, a good distribution of the hydraulic fluid can be achieved in the pressure chamber.

On the housing, a hydraulic connection can also be provided, via which a hydraulic system can be connected to the fluid channel. In this case, the hydraulic connection communicates via the fluid channel with the pressure chamber of the component feed nozzle.

The component feed nozzle is designed adjustable in volume by the closure body is biased with a biasing member in the closing direction. Such a biasing element may be a spring. If no component is supplied to the component feed nozzle, ie no component pressure acts on the closure body in the nozzle, the closure body thus closes off the component outlet. If the component pressure acting on the closure body is sufficiently large, it moves the closure body in the opening direction and thereby releases the component outlet.

Also described is a mixhead system having a component feed nozzle of the type described above.

Such a mixing head system has a mixing head in which a mixing chamber is formed. Attached to the mixing head is a component feed nozzle of the type described above. In the mixing head is a control piston which is arranged between two positions back and forth. In this case, in a first position, a component supply from the component supply nozzle into the mixing chamber is released, whereas in a second position of the control piston the component supply into the mixing chamber is interrupted and recirculation of the supplied component takes place via a recirculation groove formed in the control piston.

The mixing head system may be configured such that the releasable barrier inhibits movement of the closure body at least when the control piston is actuated to move from the second position to the first position.

To move the control piston, this can be operatively connected to a hydraulic piston, which is guided in a hydraulic cylinder and defines together with the hydraulic cylinder at least one control pressure chamber. Pressurization of the control pressure chamber exerts on the control piston a force that causes it to move to the first position. In order to provide and supply a pressurized hydraulic fluid, a control hydraulic is provided, which is connected at least to the control pressure chamber in the mixing head, but advantageously also to the hydraulic connection of the component supply nozzle.

The control hydraulics preferably have a hydraulic unit for generating pressure. This hydraulic power unit can be connected via a control pressure line to the control pressure chamber and to the hydraulic connection of the component feed nozzle. Control pressure chamber and hydraulic connection are therefore connected via a common line with the hydraulic unit. Thus, when the pressurized fluid is supplied to the control pressure space, fluid is also supplied to the pressure space in the component supply nozzle and pressure is built up. As a result, the movement of the closure body is automatically blocked when a pressure build-up in the control pressure chamber.

Alternatively, the hydraulic unit can be connected, for example, via a first control pressure line to the control pressure chamber and via a second control pressure line to the hydraulic connection of the component feed nozzle. In other words, in this embodiment, the control pressure chamber in the mixing head and the pressure chamber in the component feed nozzle are each connected via a separate line to the hydraulic unit. This has the advantage that the pressure provided by the hydraulic unit is present in each line.

In order to control the supply of the hydraulic fluid into the respective pressure chambers, a first valve can be provided in the first control pressure line and a second valve in the second control pressure line, and these valves can be connected via electrical lines to a control device. Advantageously, this control unit controls the valves such that the second valve opens before or simultaneously with the first valve. Thus, it is ensured that a blocking or inhibiting the movement of the closure body takes place at the latest when a movement of the control piston begins.

Further features and advantages of the invention will become apparent from the following embodiment, which is described with reference to the figures, in which

1 a longitudinal sectional view of a component feed nozzle according to the invention,

2 an enlarged view of the area X of 1 shows,

3 schematically shows a mixing head system according to the invention, and

4 schematically a modification of the in 3 shown mixing head system shows.

In the 1 shown component feed nozzle 10 has a multi-part housing, which is a first housing element 11 and a second housing member 12 , also called cartridge. The second housing element 12 is tubular and is partially in the first housing element at its rear end 11 added. The housing is usually connected to the second housing element 12 inserted into the head of a mixing head and is supplied through an inlet bore with the component.

A closure body, which in the present embodiment as a nozzle needle 20 is realized in the housing or the first housing element 11 and the second housing member 12 axially displaceable added. Here is the nozzle needle 20 partially in a closure body or nozzle needle guide 40 stored. The Nozzle needle guide 40 is formed as a hollow cylinder and has at its one end a flange portion 41 which is realized by a radially outwardly extending, circumferential projection. Except for the flange section 41 is the nozzle needle guide 40 in the second housing element 12 added. This means that the vast majority of the outer wall of the nozzle needle guide 40 with the inner wall of the second housing element 12 is in contact or the majority of the nozzle needle guide 40 between the nozzle needle and the second housing element 12 is arranged. The flange portion is in the radial direction between the nozzle needle 20 and the first housing element 11 and in the axial direction between the first housing element 11 and the second housing member 12 arranged.

At the front end of the second housing element 12 is a nozzle 14 provided in the a component outlet 15 is trained. With the nozzle needle 20 can the component outlet 15 closed, released or partially released. Furthermore, in the second housing 12 a component inlet 13 provided, via which a reactive component can be introduced into the component feed nozzle. Is the nozzle needle located 20 in the position in which the component outlet 15 is released or opened, then stands the component outlet 15 with the component inlet 13 in conjunction and the reactive component can be removed from the component outlet 15 flow out.

In the nozzle needle guide 40 is also a cylindrical clamping sleeve 30 provided surrounding the nozzle needle. The clamping sleeve 30 is in a in the inner surface of the nozzle needle guide 40 provided cylindrical recess and has in its outer peripheral surface a fully formed recess or groove 31 , This groove 31 lays together with one of the groove 31 facing part of the inner peripheral surface of the nozzle needle guide 40 a pressure chamber.

In the first case 11 is a channel 16 intended. This channel 16 is about a in the outer periphery of the flange portion 41 provided annular groove 43 with one in the nozzle needle guide 40 provided connection channel 42 in turn, in turn, at a location in the interior of the nozzle needle guide 40 opens, in which the groove 31 the clamping sleeve 30 located. The channel 16 is thus in flow communication with the groove 31 or the pressure chamber described above. About a connection 17 can the channel 16 be connected with a hydraulic system.

By supplying pressurized hydraulic oil through the port 17 , the channel 16 , the annular groove 43 and the connection channel 42 in the pressure chamber, a force is applied to the clamping sleeve 30 generated, which acts such that the inner diameter of the clamping sleeve 30 locally reduced and thereby the nozzle needle 20 clamped or a movement of the nozzle needle 20 is locked. By reversible deformation of the clamping sleeve 30 By a corresponding pressure build-up in the pressure chamber can therefore be created a releasable frictional or frictional connection, with which the nozzle needle can be clamped if necessary. To reduce the pressure chamber and thus allow a faster pressure build-up, a split ring 50 such in the groove 31 be arranged, that its outer peripheral surface with the inner wall of the nozzle needle guide 40 is in contact. It is thus formed by the interaction of the above elements, the releasable lock according to the invention.

As already mentioned above, the transition between the recirculation position and the firing position in a mixing head, due to the design of the control piston, leads to a brief interruption of the component flow, since neither a flow of the component into the recirculation groove of the control piston nor a flow of the component into the mixing chamber is possible , This leads to a pressure increase in the component feed nozzle.

With the embodiment of the component feeding nozzle according to the invention, however, it is now possible to actively clamp the nozzle needle in the event of an imminent or detected increase in pressure in the component feeding nozzle and thereby prevent the undesired nozzle needle movement otherwise caused by the pressure increase.

Active clamping of the nozzle needle 20 can, for example, depending on the operation of the control piston in the mixing head 60 respectively. The 3 and 4 show exemplary embodiments in which a blocking of the movement of the nozzle needle 20 depending on the operation of the control piston 61 he follows.

3 shows a mixing head system with a mixing head 60 in which a mixing chamber 62 is trained. At the mixing head 60 is a component feed nozzle 10 of the type described above attached. In the mixing head 60 there is a control piston 61 which is arranged between two positions back and forth. In this case, in a first position, a component feed from the component feed nozzle 10 into the mixing chamber 62 while in a second position of the control piston 61 the component feed into the mixing chamber 62 is interrupted and a recirculation of the supplied component via a in the spool 61 trained, not shown Rezirkulationsnut takes place.

The mixing head system is designed such that the releasable lock the movement of the closure body or the nozzle needle 20 at least then prevents if the control piston 61 is operated to move from the second position to the first position.

To move the spool 61 this is with a hydraulic piston 64 operatively connected, in a hydraulic cylinder 65 is guided and together with the hydraulic cylinder 65 at least one control pressure chamber 63 sets. A pressurization of the control pressure chamber 63 applies to the control piston 61 a force that causes it to move to the first position, in which a component feed into the mixing chamber 62 is possible. To provide and supply pressurized hydraulic fluid, in this embodiment, is a control hydraulic 70 provided, at least with the control pressure chamber 63 in the mixing head 60 but also with the hydraulic connection 17 the component feed nozzle 10 connected is.

The control hydraulics 70 has a hydraulic power unit 71 for pressure generation. This hydraulic unit 71 is via a control pressure line 72 . 73 . 74 with the control pressure chamber 63 and with the hydraulic connection 17 the component feed nozzle 10 connected. Control pressure chamber 63 and hydraulic connection 17 are therefore on a common line 72 with the hydraulic unit 71 connected. Thus, if by an unillustrated controller in the line 72 arranged valve 75 is opened, the control pressure chamber 63 fed a pressurized fluid and at the same time the pressure chamber in the component feed nozzle 10 Fluid supplied and built up a pressure. This will cause the movement of the nozzle needle 20 automatically locked when a pressure buildup in the control pressure chamber 63 he follows.

An alternative embodiment of a mixing head system is shown in FIG 4 shown. The structure of the mixing head in 4 is identical to the one in 3 Therefore, identical reference numerals are used and a re-description of the individual elements is omitted.

The design of 4 differs only by the different design of the control hydraulics. Namely, according to the present embodiment, the hydraulic power unit is 81 via a first control pressure line 82 with the control pressure chamber 63 and via a second control pressure line 84 with the hydraulic connection 17 the component feed nozzle 10 connected. In other words, in this embodiment, the control pressure space 63 in the mixing head 60 and the pressure space in the component feed nozzle 10 each with its own line with the hydraulic unit 81 connected. Accordingly, in each line of the hydraulic unit 81 provided pressure on.

In order to control the supply of hydraulic fluid in the respective pressure chambers are in the first control pressure line 82 a first valve 83 and in the second control pressure line 84 a second valve 85 intended. These valves are via electrical lines 86 and 87 connected to a control unit, not shown. The control unit now controls the valves 83 and 85 so that the second valve 85 before or simultaneously with the first valve 83 opens. This ensures that a block or suppression of the movement of the nozzle needle 20 at the latest takes place when a movement of the control piston 61 starts.

Alternatively, a sensor may be provided which determines the position of the control piston 61 in the mixing head 60 detected. Taking into account the design of the control piston 61 and the attachment point of the component feed nozzle 10 at the mixing head 60 can then be determined at which position of the control piston 61 the component flow through the control piston 61 is blocked and thus a pressure build-up in the component feed nozzle 10 takes place. The nozzle needle 20 can then be clamped during the time the component flow is blocked.

However, it is also possible that in the component feed nozzle 10 to monitor prevailing pressure, for example by a pressure sensor in the nozzle or a component supply line to the nozzle and the nozzle needle 20 to clamp when a predetermined pressure value is reached. It can thus be ensured that exactly the nozzle needle position desired for the component feed operation is maintained or determined. Thus, it can be avoided that the nozzle is opened too far at the start of shooting and too large an amount of the component is supplied.

LIST OF REFERENCE NUMBERS

10

 Komponentenzufuhrdüse

11

 First housing element

12

 Second housing element (cartridge)

13

 component inlet

14

 jet

15

 Komponentenauslass

16

 channel

17

 hydraulic connection

20

 Closure body / nozzle needle

30

 clamping sleeve

31

 Recess / groove

40

 Nozzle needle guide

41

 flange

42

 connecting channel

43

 Annular groove

50

 split ring (half shell)

60

 mixing head

61

 spool

62

 mixing chamber

63

 Control pressure chamber

64

 hydraulic pistons

65

 hydraulic cylinders

70, 80

 hydraulic control

71, 81

 hydraulic power unit

72, 73, 74,

 Control pressure line

82, 84

 Control pressure line

75, 83, 85

 Valve

76, 86, 87

 electric lines

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102007037780 A1 [0003]

Claims (13)

Component feed nozzle ( 10 ) for feeding a reaction component into a mixing head, comprising a housing having a component inlet ( 13 ) and a component outlet ( 15 ), in the housing between at least two positions movable, in particular slidably received closure body ( 20 ), wherein in a first position the component outlet ( 15 ) and in a second position the component outlet ( 15 ) is opened and a flow between the component inlet ( 13 ) and the component outlet ( 15 ) is possible, and a biasing element, which biases the closure body in the closing direction, characterized by a releasable lock, the movement of the closure body ( 20 ) can prevent in at least the opening direction. Component feed nozzle ( 10 ) according to claim 1, wherein the barrier is designed such that the movement of the closure body by adhesion, in particular a clamping, is prevented. Component feed nozzle ( 10 ) according to claim 1, wherein the releasable barrier comprises a sleeve (3) immovably arranged in the axial direction ( 30 ), in which the closure body ( 20 ) is at least partially received, and a means for applying a force to the outside of the sleeve ( 30 ) having. Component feed nozzle ( 10 ) according to claim 3, wherein the sleeve ( 30 ) is mounted in the housing in a cylinder bore and in its outer peripheral surface a recess ( 31 ), so that between sleeve ( 30 ) and cylindrical surface a pressure chamber is formed, and wherein a fluid channel ( 42 ) is provided which opens into the pressure chamber. Component feed nozzle ( 10 ) according to claim 4, wherein on the housing ( 11 ) a hydraulic connection ( 17 ) or pneumatic connection is formed, which via the fluid channel ( 42 ) communicates with the pressure space. Mixing head system with a mixing head ( 60 ), in which a mixing chamber ( 62 ) is formed, a mounted on the mixing head component feed nozzle ( 10 ) according to one of claims 1 to 5, and a control piston ( 61 ), which in the mixing head ( 60 ) is reciprocable between two positions, wherein in a first position, a component feed from the component feed nozzle ( 10 ) into the mixing chamber ( 62 ) and in a second position the component feed into the mixing chamber ( 62 ) is interrupted and a recirculation of the supplied component via a recirculation in the control piston ( 61 ) he follows. Mixing head system according to claim 6, wherein the system is designed such that the releasable lock the movement of the closure body ( 20 ) at least then prevents, when the control piston ( 61 ) is actuated to move from the second position to the first position. Mixing head system according to claim 6 or 7, wherein the control piston ( 61 ) with a hydraulic piston ( 64 ) operatively connected in a hydraulic cylinder ( 65 ) and together with the hydraulic cylinder ( 65 ) at least one control pressure space ( 63 ), wherein a pressurization of the control pressure chamber ( 63 ) causes a movement of the control piston in the first position, and wherein a control hydraulic ( 70 ; 80 ) is provided for supplying a hydraulic pressure with the control pressure chamber ( 63 ) and the hydraulic connection ( 17 ) of the component feed nozzle ( 10 ) connected is. Mixing head system according to claim 8, wherein the control hydraulics ( 70 ) a hydraulic power unit ( 71 ) for generating pressure, and wherein the hydraulic unit ( 71 ) via a control pressure line ( 72 ) with the control pressure space ( 63 ) and with the hydraulic connection ( 17 ) of the component feed nozzle ( 10 ). Mixing head system according to claim 8, wherein the control hydraulics ( 80 ) a hydraulic power unit ( 81 ) for generating pressure, and wherein the hydraulic unit ( 81 ) via a first control pressure line ( 82 ) with the control pressure space ( 63 ) and via a second control pressure line ( 84 ) with the hydraulic connection ( 17 ) of the component feed nozzle ( 10 ). Mixing head system according to claim 10, wherein in the first control pressure line ( 82 ) a first valve ( 83 ) and in the second control pressure line ( 84 ) a second valve ( 85 ) is provided and the valves via electrical lines ( 86 . 87 ) are connected to a control device, wherein the control device the valves ( 83 . 85 ) such that the second valve ( 85 ) before or simultaneously with the first valve ( 83 ) opens. Method for controlling a mixing head system according to one of Claims 6 to 11, characterized by the steps of blocking the movement of the closure body ( 20 ) in at least the opening direction when the spool is operated to move from the second position to the first position. A method of controlling a component feed nozzle according to any one of claims 1 to 5, comprising the step of inhibiting the movement of the closure body ( 20 ) in at least the opening direction when a predetermined component pressure is detected.

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