WO1990003849A1

WO1990003849A1 - Spray pump

Info

Publication number: WO1990003849A1
Application number: PCT/EP1989/001177
Authority: WO
Inventors: Raimund Andris
Original assignee: Mega-Plast Dosiersysteme Gmbh & Co.
Priority date: 1988-10-07
Filing date: 1989-10-07
Publication date: 1990-04-19
Also published as: DE3834091A1; DE3834091C2

Abstract

Spray pump for intermittently spraying liquid substances from bottle or can-shaped containers with a bellow made of elastic synthetic material, which connects two housing parts of dimensionally stable synthetic material between which it is arranged; said housing parts move axially relative to one another in a telescopic manner between two stroke stops and are moved back by the axial restoring forces of the bellow. At both ends of the bellow, pump valves are provided with collar-like radial-elastic annular wall sections integral with the bellow and hermetically applied to the surface of the casing of a second valve part in the shape of a peg, a ring or a pot. In order to avoid excessively low spraying pressures at the beginning and end of a delivering stroke by means of a simple design, which does not require a much increased manual operating pressure, a stop device (8, 48, 49; 53, 54, 55, 59, 62), comprised of elastically cooperating parts of the two housing parts (1, 2) and which only operates over a short distance, is provided between the two telescopically movable housing parts (1, 2); moreover an axially mobile valve body (44, 45; 65, 45) is arranged inside the bellow (3), which opens the pump valve on its suction side at the end of each delivering stroke.

Description

Spray pump

The invention relates to a spray pump for intermittent spraying of liquid substances from bottles or cans like containers with a bellows made of elastic plastic, which is arranged connecting between two housing parts made of dimensionally stable plastic, which is telescopically movable in the axial direction between two stroke limits and by the axial restoring forces of the bellows are resettable, pump valves being arranged at the two ends of the bellows, each of which has radially elastic, sleeve-like annular wall sections arranged in one piece on the bellows, each of which seals on the outer surface of a peg-shaped, ring-shaped or cup-shaped second valve partly concern. In a known liquid pump with bellows (GB-PS 1 599 744), the open end of the bellows is provided with a mn cuff-like, radially expandable extension, which sealingly encloses an inwardly projecting tube extension of the housing part and at the same time acts as a movable closing element of the outlet valve. A closed end wall is provided at the opposite end of the bellows, against which a swivel lever provided with a handle part presses. The suction-side valve is arranged in a neck of the liquid container specially designed for this purpose.

In another known bellows metering pump (DE-OS 35 09 178), the two housing parts which are axially displaceable relative to one another are each provided with a transverse wall running at right angles to the axis of the bellows, these transverse walls on the mutually facing sides each having ring ribs for sealingly receiving one bellows end each exhibit. In addition, bores with valve seat surfaces and the associated closing elements of the pump valves are arranged in the two transverse walls. The movable closing elements of these pump valves are each designed as separate individual parts and the closing element of the suction-side pump valve is loosely guided by means of ribs arranged in a star shape in a tubular extension of the transverse wall of the container and secured against falling out by claw-like fingers protruding into the interior of the bellows. The closing element of the output-side pump valve has integrally molded spring elements which have a small axial closing element Press pressure on the valve seat and hold it in the closed position.

In these known metering and spray pumps, if they are to be used for spraying liquids, the phenomenon occurs that at the beginning and at the end of a dispensing stroke, liquid emerges dropwise or in the form of a weak jet from the spray nozzle, that is to say part of the spray nozzle dispensed liquid is not sprayed. The reason for this is that the _'generation of the Sprüheffektes a certain minimum pressure - the Sprühdruck- within the bellows must be present in the case of these known devices at the beginning of a pump stroke when the exhaust valve opens already ,, not yet available and the At the end of the pumping stroke gradually drops below the spray pressure threshold.

The patent application P 38 28 811.7 also specifies options by which the uncontrolled, low-pressure flow of liquid from the spray nozzle at the end of a dispensing stroke can be prevented, in the form of a valve opener that opens the suction valve at the end of the dispensing stroke that the remaining excess pressure inside the bellows can escape through the suction valve into the liquid container and close the pump valve on the output side. However, a possibility of preventing the uncontrolled escape of liquid from the spray nozzle under a pressure that cannot cause spraying at the start of a dispensing stroke is also not specified there. The invention has for its object to provide a spray pump of the generic type, in which the uncontrolled escape of liquid from the spray nozzle under reduced, for a spray effect too low pressure at the beginning and end of a delivery stroke is prevented with the simplest possible means, taking into account is that such spray pumps are mass-produced items that are manufactured millions of times and that should therefore consist of as few, easy-to-assemble individual parts as possible.

At the same time, it should be ensured that the measures by which this above object is to be achieved do not result in a noticeable increase in the working pressure in such a way that the working pressure to be applied manually is substantially above the pressure which is briefly referred to below as "spray pressure" is required to produce the desired spray effect.

According to the invention, three different solutions are proposed according to claims 1 to 3, which have in common that at the beginning of each delivery stroke by exerting a certain minimum pressure on the housing part carrying out the lifting movements, the pump valve on the output side only opens when the minimum pressure necessary to overcome the pressure point on Bellows pending. Of course, the pressure point device must be designed in all three cases so that the force required to overcome the pressure point is also sufficient to generate the spray pressure in the bellows. Furthermore, all three solutions have the same advantage that immediately after overcoming the so-called pressure point, the pressure point resistance is practically no longer available, so that the entire force exerted on the moving housing part is available for generating the spray pressure within the bellows or the discharge channel and the spray nozzle. The resistance that creates the pressure point disappears the moment the pressure point is overcome. The rest of the delivery stroke is practically inevitably carried out with the force used to overcome the pressure point, so that an immediate and continuous spraying of the liquid to be dispensed is guaranteed.

There is also a commonality between the three solutions with regard to preventing dripping at the end of the delivery stroke. In all three cases it is namely ensured that at the end of the delivery stroke the pressure causing the opening of the output-side pump valve is suddenly removed from it, so that a sudden closing of the output-side pump valve can also occur, which prevents dripping. While this occurs in the solution of claim 1 by opening the suction-side valve, in the solutions of claims 2 and 3 an additional closing device takes place in the region of the discharge-side end of the bellows, through which the interior of the bellows, in which the spray pressure still prevails, the output-side pressure valve is separated, so that the supply of the liquid medium from the inside of the bellows to the output-side pump valve is interrupted. This also makes an instant Closes the pump valve on the output side and thus prevents a drop of eight.

While the claims 4 to 7 advantageous configurations relate to the mechanical means provided according to claims 1 or 2 for generating the pressure point, the configurations of claims 8 and 9 serve to advantageously form a valve opener for the suction-side pump valve. ___ The locking device provided according to claim 10, like the subjects of claims 11 and 12, has the advantage that no additional individual parts are required for its implementation, it being clear that the displacement body provided according to claim 11 and 12 also has the important task to fill the interior of the bellows almost completely at the end of a delivery stroke, so that as little liquid as possible remains in it and that, especially during the first suction stroke, there is as little compressed air in the bellows as possible, which could prevent the medium from being sucked into the screwed-on container.

The solutions according to the invention are explained in more detail with the aid of the exemplary embodiments shown in the attached drawing figures. It shows:

1 shows in section a spray pump with a pressure point locking device; FIG. 2 shows a section II-II from FIG. 1; Fig. 3 shows a spray pump like Fig. 1 with another Pressure point locking device in the normal rest position of the two housing parts; Fig. 4 shows the spray pump of Fig. 3 at the end of a delivery stroke; Fig. 5 and 6 in an enlarged view the suction side

Valve parts of the spray pumps of Fig. 1 and 3, 4; Fig. 7 shows the lower section of the front with a

Valve pin provided displacement body; Fig. 8 shows a spray pump in section with another

Pressure point device in the rest position of the two

Housing parts; 9 shows the spray pump of FIG. 8 at the end of a delivery stroke; 10 the displacement body as a single part in section; 11 is the top end view of the displacement body of FIG.

10; 12 shows the lower forehead of the displacement body of FIG.

10; Fig. 13 shows another spray pump with a hydraulic

Pressure point device and closing device in the area of the output-side pump valve in the rest position of the two housing parts; Fig. 14 in section the spray pump of Fig. 13 at the end of a

Output hubs; 15, 16 and 17 enlarged sections of FIGS. 13 and 14 in different positions of the hydraulic

Components generating pressure point and FIG. 18 the suction-side valve parts of the spray pump of FIGS. 13 and 14 in an enlarged sectional view. In the following description of the examples, the parts that occur jointly in each of the exemplary embodiments are identified by the same reference numbers, even if these parts are designed differently in detail.

1, 3, 4, 8, 9 as well as 13 and 14 each of the spray pumps shown in full each consist of a total of four individual parts, namely a first housing part 1 and a second housing part. 2, from a bellows 3 and a substantially cylindrical displacement body 4. While the two housing parts 1 and 2 and the displacement body 4 are each made of solid, dimensionally stable plastic, the bellows 3 consists of a rubber-elastic, soft plastic, which is also in is able to apply the restoring forces necessary for the pumping process between the two housing parts 1 and 2.

The housing part 1 consists of a substantially cylindrical, sleeve-like, relatively thin-walled hollow body 5 with an approximately half of its axial extent, slightly enlarged in diameter, lower guide section 6. This guide section 6 is axially displaceable in a guide cylinder 7 of the housing part 2 axially movably guided, wherein an inwardly projecting annular rib 8 overlaps the upper radial shoulder 9 of the guide section 6 at the upper edge and acts as an upper stroke limitation. The hollow body 5 of the housing part 1 is surrounded at a radial distance concentrically by a likewise thin-walled and cylindrical outer wall 10, which is approximately half as long as the hollow body 5. This outer wall 10 can be telescopically inserted into a cylindrical outer sleeve 11 of the housing part 2 until it limits the stroke movement of the housing part 1 is seated on the annular cover wall 12 of a screw cap 14 provided with an internal thread 13. The likewise thin-walled guide cylinder 7 is provided at its lower end protruding into the screw cap 14 with a tapered section 15, which has a flat end wall 16 with a central hose connector 17 on the outside and a cylindrical support ring 18 on the inside. The hose connector 17 and the support ring 18 are each arranged concentrically to the common housing axis 20, the diameter of the support ring 18 is approximately twice as large as the diameter of the hose connector 17. The end wall 16 has a bore 19 in its center through which the in Hose connection stuzten 17 attached suction hose 21 rait the interior of the guide cylinder 7 and the support ring 18 is in communication.

The screw cap 14 is suitable for screwing the housing part 2 onto the neck of a can-like or bottle-like container provided with a corresponding external thread. Accordingly, the guide cylinder 7 is designed in its diameter so that it can be inserted into the neck of this container. The length of the suction hose 21 is adapted to the length of the container so that the suction hose 21 extends to the bottom of the container. The housing part 1 is provided at its upper end section with a radial nozzle nozzle 22 which forms the dispensing mouthpiece and into which a spray nozzle 23 is inserted. This spray nozzle 23 has a narrow spray opening 24 which is connected to an at least partially annular swirling space 25 of the nozzle connection 22. The swirling space 25 is connected via a wall opening 26 to an annular channel 27, which is formed between a cylindrical inner wall surface 28 adjoining the hollow body 5 and the outer annular surface 29 of an annular extension 30 projecting concentrically to the housing axis 20 into the hollow space of the hollow body 5 is and also occupies a concentric position to the housing axis 20.

In the exemplary embodiments described here, this extension 30 is designed as a cylindrical ring wall and is integrally formed on the closed end wall 31 of the housing part 1. This extension 30 has, on its outer annular surface 29 on its side facing the nozzle connection 22 or distributed over the entire circumference, a plurality of axial conveying channels 32 in the form of axial grooves, which, however, do not extend over the entire axial length of the annular surface 29, but rather only up to extend at the level of the spray nozzle axis 33 and which are each provided on the lower end face of the extension 30 with openings 34 through which they are connected to the interior of the extension 30 or the bellows 3. The approach 30 is of a relatively thin-walled, radial-ela stisc en enclosed annular wall portion 35, which rests with a certain prestress sealingly on the outer ring surface 29 and which forms the upper end portion of the bellows 3, on which it is integrally formed. The axial length of the annular wall section 35 projects beyond that of the conveying channels 32, so that the upper end section of the annular wall section 35 bears all around the uninterrupted part of the annular surface 29 of the projection 30 and, due to its radial elasticity, forms the movable closing element of the pump valve on the output side.

So that none of the liquid to be sprayed can get into the interior of the hollow body 5 from the annular channel 27, the circumference of the annular wall section 35 of the bellows 3 is provided with a circumferential sealing rib 36 which bears sealingly against the cylindrical inner surface 28 of the hollow body 5 .

A cylindrical expansion wall section 37, which is provided with a greater wall thickness than the foldable part of the bellows 3, adjoins the folding section of the bellows 3 which extends approximately over the length of the hollow body 5 and consists of zigzag-shaped folding rings. This expansion wall section 37 protrudes with its lower end sealingly and directly on the end wall 16 in the support ring 18 of the housing part 2, and it is provided with an annular end wall 38 which has a central passage opening 39 and a concentrically arranged inwardly directed, thin, cylindrical and radial - Has elastic ring wall 40. On its outer lateral surface, the stretching wall section 37 has a Circumferential, umbrella-like sealing lip 41 is provided, which bears sealingly on the inner surface of the lower section 15 of the guide cylinder 7, and in connection with the ventilation openings 42 arranged in the end wall 16 on the one hand allows air to enter the container and on the other hand that prevents unwanted outflow of the liquid to be sprayed.

The already mentioned, located inside the bellows 3 displacement body 4 has a cylindrical shape and a length that is shorter by the stroke length of a pump stroke than the axial distance between the end wall 31 of the housing part 1 from the end wall 38 of the bellows 3 The diameter is kept smaller than the inside diameter of the bellows 3 or the expansion wall section 37, so that the liquid to be sprayed can flow past it through the bellows 3. At the level of the lowest fold ring of the bellows 3, the displacement body 4 has an annular rib 43 which, in cooperation with the lowest fold ring 69, causes an axial movement limitation for the displacement body 4. The diameter of the displacement body 4 is held at least at its upper end section so that it can plunge into the cylindrical cavity of the projection 30 with radial play up to the end stop on the end wall 31 of the housing part 1.

At the lower end, the displacement body 4 is provided with a partly conical, partly cylindrical, central valve pin 44, which has a smaller diameter and which is provided on its circumference with four distributed axial grooves 45. As can be seen from the drawing, these axial grooves do not extend over the entire length of the valve pin 44, but only in the area of the upper half of the valve pin 44. Around this valve pin 44 in cooperation with the radially elastic ring wall 40 on the one hand as axial To be able to use the movable closing element of the suction-side pump valve and, on the other hand, also as a valve opener for the suction-side pump valve, the conical part of the valve pin 44 is matched to the inside diameter of the ring wall so that this ring wall 40 under the pressure conditions prevailing in the bellows 3 during an output stroke until shortly before the end of the delivery stroke sealingly rests below or outside the axial grooves 45 on the uninterrupted conical lateral surface and the suction-side pump valve is thus closed, but only when the displacement body 4 at the end of the stroke movement of the arrow 46 in the direction of arrow 46 Housing part 1 of the end wall 31 with its valve pin 44 is pressed so far into the ring wall 40 that the lower ends of the axial grooves 45 also dip into this ring wall 40 and establish a connection between the interior of the bellows 3 and the passage opening 39, which via the Bore 19 and the suction hose 21 communicates with the interior of the container.

By opening the suction-side valve, the one prevailing inside the bellows 3 becomes at the end of the discharge stroke Overpressure or spray pressure abruptly reduced, so that the outlet-side valve closes abruptly and nothing of the remaining liquid, which is still in the bellows 3, can reach the spray nozzle 23. This will prevent dripping.

So that the displacement body 4 of the following backward movement of the housing part 1 immediately follows and can not be held by the radially stretched ring wall 40, which includes the valve pin 44, are for safety's sake on the valve pin 44 surrounding annular end face 50 two diametrically opposite , Finger-like spring elements 51 molded so that their lower, arcuate end portions 52 are resiliently supported on the annular end wall 38 of the bellows 3.

In order to ensure in such a spray pump that even in the initial phase of the pressure stroke movement of the housing part 1 in the direction of arrow 46, the valve on the output side does not open before the spray pressure in the bellows 3 is reached, in the exemplary embodiments of FIGS. 1 and 2, 3 and 4, and 8 and 9 each have a device for generating a mechanical pressure point between the housing part 1 and the housing part 2. This pressure point device is intended to ensure that before opening the pump valve on the output side, ie before the radial lifting of the elastic ring wall section 35 from the ring surface 29 of the extension 30, onto the cover wall 31 of the Housing part 1 in the direction of arrow 46 is exerted such a strong force that after overcoming the pressure point during the remaining pumping stroke in the bellows 3, the spray pressure, which is sufficient to achieve a satisfactory spray effect on the spray nozzle 23, is fully effective.

In the exemplary embodiment in FIGS. 1 and 2, this mechanical pressure point device is provided in the form of a tongue-shaped section 48 of the hollow body 5 which is freely cut by two axila slots 47. This tongue-shaped section 48 is provided on its outside with a projecting transverse locking rib 49 which, in the upper end position of the housing part 1, that is to say in the starting position, lies above or outside the inwardly directed annular rib 8 of the guide cylinder 7 of the housing part 2 and that when the housing part 1 is actuated in the direction of arrow 46 of the downward movement, there is initially a resistance which is so great that the force required to overcome it is also sufficient to generate the spray pressure inside the bellows 3.

The spray pump shown in FIGS. 3 and 4 differs from that of FIGS. 1 and 2 only in that it is provided with a different pressure point mechanism. The rest of the structure is the same.

This pressure point mechanism consists of two diagonally opposed ratchet cams 53 and 54 arranged diametrically opposite one another on the inside of the outer sleeve 11 of the housing part 2, on which the Bottom edge 54 of the outer wall 10 of the housing part 1 is initially seated after a short initial movement in the direction of the arrow 46. The further downward movement of the housing part 1 is opposed to such a great resistance that the force required to overcome it is sufficient in any case to generate the spray pressure required for a satisfactory spray effect inside the bellows 3. The thin walls of the outer sleeve 11, on the one hand, and the outer wall 10, on the other hand, provide the required elasticity, which enables the pressure point to be overcome or the further downward movement with simultaneous radial deflection of the locking cams 53 and 54. The two parts 10 and 11, which are telescopically guided one into the other anyway with radial play, are deformed slightly elliptically.

With both pressure point devices it is also ensured that the force exerting the pressure stroke of the housing part 1 no longer counteracts any noticeable mechanical resistance after overcoming the latching resistance causing the so-called pressure point and it is then fully available for building up the spray pressure in the bellows 3.

The presence of the mechanical pressure point device thus ensures that at the beginning of an output pump stroke the output-side pump valve is only opened when the force required to generate the spray pressure inside the bellows 3 is exerted on the housing part 1 in the direction of arrow 46 and that as a result thereof a premature dripping out of liquid from the spray nozzle 22 is avoided. On the other hand, it is also ensured that at the end of an output pumping stroke, when the housing part 1 and the displacement body 4 are in the position shown in FIG. 4, any excess pressure in the interior of the bellows 3 is reduced because the suction-side pump valve as described above is opened by immersing the axial grooves 45 of the valve pin 44 in the radially elastic ring wall. This also ensures that a dropwise or uncontrolled escape of liquid from the spray nozzle 23 at the end of a dispensing pump stroke is avoided.

It can be seen from FIG. 4 that in the lower end position of the housing part 1 carrying out the pumping strokes, the annular sealing lip 41 of the bellows 3 is pressed down so far from the lower end edge of the hollow body 5 that it is pushed away from the inner surface of the lifts in diameter tapered end portion 15 and at that moment its sealing function is canceled. Via the ventilation openings 42 and the annular gap surrounding the cylindrical guide section 6, the interior of the container, onto which the screw cap 14 is screwed, is in direct contact with the outside atmosphere, so that pressure compensation can take place.

In the spray pump shown in FIGS. 8 and 9, other means are provided for generating the mechanical pressure point than in the two spray pumps of FIG. 1, 3 and 4, and there is also no valve opener on the suction-side pump valve. Instead of the valve opener, the end portion of the projection 30 projecting into the bellows 3 is provided with an annular collar 57 which is tapered in the outer diameter and which sits on the uppermost fold ring 68 of the bellows 3 in a sealing manner at the end of an output stroke and thus the further supply of liquid from the inside of the Bellows 3 terminated or interrupted in the delivery channels 32. This also prevents that liquid can escape from the spray nozzle 23, for example dropwise, under reduced pressure if, at the end of a pressure stroke, the pressure prevailing in the bellows 3 drops or would drop below the spray pressure. A valve opener for the intake-side valve is not required in this case.

To generate the mechanical pressure point, the housing part 1 is in the center of the hollow cylindrical projection 30 with a locking pin

58 provided, which has a conical locking shoulder 59 and then a cylindrical guide pin 60 tapered in diameter. As a counter bearing for the locking pin 58, a hollow cylindrical displacement body 4 is provided, which at its upper end has four radial-elastic locking segments 62 which are separated from one another by axial slots 61, but which are otherwise integrally formed, and which are each provided with a funnel-like conical end face 63, on which the rest shoulder

59 of the locking pin 58 is seated in the starting position of the housing part 1, as shown in FIG. 8. The guide pin 60 projects centering between the locking segments together form a central cylindrical bore 64. At the lower end, the displacement body 3 is provided with a truncated cone-shaped valve pin 65 which, like the conical part of the valve pin 44 in the exemplary embodiments in FIGS. 1 to 4, is an opening and closing valve part with the radially elastic annular wall 40 of the bellows 3 interacts. This valve pin 65 has no axial grooves on its outer surface. However, it is therefore also not suitable for opening the suction-side pump valve at the end of a pressure stroke or discharge stroke. The valve pin 65 is surrounded by a thin, interrupted by axial slots 66, also integrally formed on the displacement body 4. Ring wall 67, which is supported during the output stroke of the housing part 1 in the direction of arrow 46 on the end wall 38 of the bellows 3. During this time, the valve pin 65 is pressed somewhat deeper into the ring wall 40. If, for example, an axial pressure is exerted on the end wall 31 of the housing part 1 in the direction of arrow 46 in the direction of arrow 46 in order to carry out an output or pressure stroke, this pressure is first applied via the locking shoulder 59 of the ratchet pin 50 transferred to the locking segments of the displacement body 4 and pushed so far down that its ring wall 67 sits on the end wall 38 of the bellows. Although a slight pressure increase is generated inside the bellows 3, this is not sufficient to open the pump valve on the output side. It is now necessary to intensify the axial pressure in the direction of arrow 46 on the end wall 31 of the housing part 1 until it is between the conical locking shoulder 59 on the one hand and the conical end faces 63 of the locking segments 62 on the other hand existing locking resistance has been overcome and the cylindrical locking pin 58 is immersed in the locking segments 62 with simultaneous radial deflection thereof. By appropriate surface finish and inclination of the zusammenwir¬ together kenden conical surfaces of the detent shoulder 59 on the one hand and the locking segments 62 on the other hand it is ensured that the w bz for overcoming the pressure point ^'. of the locking resistance required axial pressure is certainly sufficient to generate the spray pressure required for an immediate spraying of the liquid inside the bellows 3. In practice, this means that the moment the pressure point is overcome and the locking pin 58 dips into the locking segments 62 of the displacement body 4, the required spray pressure is immediately generated in the bellows 3, so that the Delivery channels 32 and the radially stretched annular wall section 35 of the bellows 3 arrives in the spray nozzle 23 with the required spray pressure liquid arrives at the spray opening 24 and the spray effect comes about immediately.

Experience shows that it can be assumed that the pressure applied to overcome the pressure point on the housing 1 in the direction of arrow 46 is sufficient to complete the dispensing stroke while maintaining the required spray pressure until the collar 57 of the projection 30 closes on the top pleated ring 68 of the bellows 3 is seated, or until in the previously described exemplary embodiments of FIGS. 1 to 4 suction-side valve for generating a pressure compensation is opened by immersing the axial grooves 45 in the elastic ring wall 40. This end position is shown in FIG. 9 and FIG. 4.

Iff now at the end of the discharge stroke of the thrust end on the housing part 1 in the embodiment of FIGS. 8 and 9, position illustrated 8 sets by ^'the restoring force of the Faltenbalgε 3 instantly Rückwärts¬ movement of the housing part 1 in the in Fig. A. During this backward movement, the displacement body 4 is also initially carried along until its ring rib 43 is stopped by the lowest fold ring 69 of the bellows 3. The locking pin 58 returns to its initial position shown in FIG. 8, in which its locking shoulder 59 flies against the conical end faces 63 of the locking segments 62. So that the lowest rib ring 69 resting on the annular rib 43 does not hinder the inflow of liquid into the upper part of the bellows 3, it is provided with a few interruptions 43 '.

In the exemplary embodiment, which is shown in FIGS. 13 and 14 and 15 to 18, no means for generating a mechanical pressure point are provided, which means that the two housing parts 1 and 2 neither a tongue-shaped section 48 with a locking cam 49 nor Have locking cams 53. Instead, in order to generate a hydraulic pressure point, the shoulder 30 of the housing part 1, which is provided with a smaller inner diameter, is provided with a closure collar 70 which is integrally formed as an extension and which, as shown in FIGS. 13 and 15, in the starting position of the two housing parts 1 and 2 sealingly abuts the inner surface of the uppermost inwardly projecting fold ring 68. An externally circumferential annular groove 71 adjoins this closing collar 70, which in turn ends at an annular collar 57, which is also present in the embodiment of FIGS. 8 and 9, albeit in a slightly different form, but for the same purpose is. The annular groove 71 is designed such that it can freely receive the uppermost pleated ring 68 after a certain initial movement of the housing part 1 and the locking collar 70 during the remainder of the pump stroke, so that liquid can flow through the annular groove 71 unhindered to the delivery channels 32 or through the output-side pump valve can flow to the spray nozzle 23. This functional position is shown in FIG. 16. As can be seen from FIGS. 14 and 17, the fold rings of the bellows 3 are pressed together towards the end of the discharge stroke so far that the uppermost fold ring 68 rests against the collar 57 and prevents any further liquid supply to the delivery channels 32. This effectively prevents liquid from dripping from the spray nozzle 23.

The generation of the hydraulic pressure point occurs in that at the beginning of an output or. Pressure stroke is initially prevented by the closing collar 70 still sealingly against the inner surface of the uppermost fold ring 68 and the supply of liquid from the inside of the bellows 3 to the delivery channels 32. By increasing the pressure in the direction of arrow 46 but then by the simultaneous downward movement of the Housing part 1 in relation to the housing part 2 and the shortening and radial expansion of the bellows 3 taking place, a lifting of the locking collar 70 from the uppermost folding ring 68 are effected, so that the passage of liquid to the delivery channels 32 is released ^ However, there is an axial pressure necessary, which is certainly sufficient to generate the spray pressure inside the bellows 3, which is necessary for the perfect spraying of the liquid.

As with the exemplary embodiments described above with the mechanical pressure point devices, the spray pump is also achieved with a hydraulic pressure point device in this case, that the force required to overcome the pressure point while maintaining the required spray pressure in the bellows 3 results in the delivery stroke being carried out completely.

The displacement body 4 provided in the exemplary embodiment in FIGS. 14 and 15 consists of a solid cylindrical body with an upper part 4 ′ which is tapered in diameter and which can dip into the cylindrical cavity of the projection 30. At the lower end, the displacement body 4 also has a conical valve pin 65, which is surrounded by a slotted ring wall 67. In contrast to the valve pin 65 of the hollow-cylindrical displacement body 4 shown in FIGS. 8 to 12, in the present case the valve pin 65 in the upper part of its conical outer surface again has four axial grooves 45, which serve the same purpose as the axial grooves 45 of the valve pin 44 in the exemplary embodiments of FIGS. 1 to 4. This means that the valve pin 44 in exemplary embodiments 1 to 7 could also have the shape shown in FIGS. 13, 14 and 18 and described above with 'conical axial grooves 45.

In connection with the closing collar 57, however, it would not be necessary to open the suction-side valve at the end of the discharge stroke by immersing the axial grooves 45 in the elastic ring wall 40. As an additional security measure, however, this can easily be provided, especially since this does not result in any additional costs.

Otherwise, the valve pins 44 and 65 of the displacement body 4 interact with the elastic ring wall 40 in such a way that liquid is sucked into the bellows 3 through the ring wall 40 past the valve pin 44 and 65, respectively, during the dispensing stroke following a dispensing stroke. The valve pin 44 or 65 is temporarily slightly pushed out of the annular wall 40. With the vertical normal position of the spray pump, the valve pin 44 or 65 returns to its closed position at the end of a delivery stroke.

4, 9 and 14 it can be seen that the interior of the bellows is almost completely filled by the displacement body 4 at the end of an output pump stroke. This means that during the first aspiration stroke, which is applied to a container for aspirating liquid after the spray pump has been placed, there is only one there is a small amount of air in the bellows and that is why the suction effect actually takes place. Since air is compressible, only a small amount of air could be pressed out of the bellows 3 through the suction valve without the displacement body 4 during the first pressure stroke or discharge stroke, ie when the housing part 1 is actuated in the direction of arrow 46; the subsequent suction effect would be too weak for - liquid to be sucked into the bellows.

Claims

Patent claims:

1. Spray pump for intermittent spraying of liquid substances from bottle- or can-like containers with a bellows made of elastic plastic, which is arranged connecting between two housing parts made of dimensionally stable plastic, which can be moved telescopically in the axial direction between two stroke limits and through the axial Restoring forces of the bellows can be reset, pump valves being arranged at the two ends of the bellows, each of which has radially elastic, sleeve-like annular wall sections which are arranged in one piece on the bellows and each sealingly on the outer surface of a cone, ring or pot - Shaped second valve part, characterized, that to generate a mechanical pressure point between the two telescopically movable housing parts (1, 2), a spring-acting parts of the two housing parts (1, 2), only over a short distance effective locking device (8, 48, 49; 53, 54 , 55, 59, 62) and that in the interior of the bellows (3) an axially movable valve opener (44, 45; 65, 45) is arranged, which opens the suction-side pump valve at the end of a discharge stroke;

2. Spray pump for intermittent spraying of liquid substances from bottle- or can-like containers with a bellows made of elastic plastic, which is arranged connecting between two housing parts made of dimensionally stable plastic, which can be moved telescopically in the axial direction between two stroke limits and through the axial Restoring forces of the bellows can be reset, pump valves being arranged at each of the two ends of the bellows, each of which has radially elastic, cuff-like ring wall sections arranged in one piece on the bellows, each of which seals on the lateral surface of a cone-shaped, ring-shaped or pot-shaped one second valve in part, characterized in that to generate a mechanical pressure point between the two telescopically mutually movable housing parts (1, 2) consisting of resiliently interacting parts of the two housing parts (1, 2), only over a short Route effective locking device (59, 62) is arranged, and that the discharge-side pump valve means includes a closure (57) is connected upstream of each of which separates the interior of the bellows (3) at the end of ^• delivery stroke from ausgabe¬ side pump valve (30, 85) .

3. Spray pump for intermittent spraying of liquid substances from bottle or can-like containers with a bellows made of elastic plastic, which is arranged connecting between two housing parts made of dimensionally stable plastic, the telescopic in the axial direction between two stroke limits against each other and movable by the Axial restoring forces of the bellows can be reset, pump valves being arranged at the two ends of the bellows, each of which has radially elastic, cuff-like annular wall sections arranged in one piece on the bellows, each of which seals on the lateral surface of a pin, ring or Cup-shaped second valve part bear, characterized in that, in order to generate a hydraulic pressure point, the ring-shaped or cup-shaped extension (30) of the housing part (1) carrying out the pump strokes and surrounded by the output-side ring wall section (35) of the bellows (1) has a closing collar (70) t, on which the fold ring (68) of the bellows (3) closest to the ring wall section (35) lies sealingly in the initial phase of a delivery stroke, so that the fold ring (68) freely accommodates the closing collar (70) on the output side Connects annular groove (71) and that an annular collar (57) is arranged on the output side of the annular groove (71), against which the pleated ring (68) lies in a closing manner at the end of an output stroke.

Spray pump according to claim 1 or 2, characterized in that the latching device between a central latching pin (58) of the housing part (1) carrying out the lifting movements and an axially movable in the bellows (3), which is located on the output-side end wall (38) of the bellows (3 ) supporting displacement body (4) is formed.

Spray pump according to claim 4, characterized in that the displacement body (4) is provided on its output-side end section with a plurality of radially elastic locking segments (62) with obliquely inclined support surfaces (63) between which the locking pins (58) are immersed after a predetermined axial pressure has been exceeded can.

Spray pump according to claim 1 or 2, characterized in that the latching device between telescoping wall sections (7, 48; 10, 11) of the two housing parts (1, 2) is formed in such a way that the wall section (48, 11) of the a housing part (1; 2) is provided with at least one obliquely radially projecting locking rib (49; 53, 54) which with the end edge (8; 55) of a wall section (7; 10) of the other housing part (2, 1) deflecting cooperates.

7. Spray pump according to claim 6, characterized in that the ^• locking rib (49) on a through axial slots (47) freeschnit¬ th locking tongue (48) of one housing part (1) is arranged.

8. Sp aypumpe according to claim 1, characterized in that a valve pin (44; 65) is arranged as a valve opener on the end face of an axially movably mounted displacement body (3) in the bellows (3), which with a closing cone in a collar or sleeve-shaped Valve part (40) of the outlet end wall (38) of the bellows (3) protrudes and is provided on its outer surface with one or more axial grooves (45), each of which is in the final phase of a dispensing stroke due to the direct action of the moving housing part (1) penetrate into the collar-shaped valve part (40) on the displacement body (3).

9. Spray pump according to claim 8, characterized in that the displacement body (3) is held in an axial position by spring elements (51) formed on the end face, in which the axial grooves (45) of the valve pin (44) outside the collar-shaped valve part (40) lie.

10. Spray pump according to claim 2, characterized in that the closing device from an annular collar (57) of the output side ring wall portion (35) of the bellows (3) comprised ring-shaped or pot-shaped extension (30) of the housing part (1) carrying out the pump strokes, which, at the end of an output stroke, is closest to the folding ring (68) of the bellows (3).

11. Spray pump according to claim 3, characterized in that in the interior of the bellows (3) an axially movable valve opener (65, 45) is arranged, which opens the suction-side pump valve in each case at the end of a delivery stroke.

12. Spray pump according to claim 11, characterized in that a valve pin (65) is arranged as a valve opener on the end face of a displacer (4) which is axially movably mounted in the bellows (3) and which has a closing cone in a collar-shaped valve part (40) the suction-side end wall (38) protrudes and is provided on its outer surface with one or more axial grooves (45), each of which penetrate into the collar-shaped valve part (40) in the final phase of a delivery stroke