SE441380B - DISPENSING PUMP FOR EXHAUSTING A PRODUCT FROM A CONTAINER - Google Patents

Abstract

In a hand-operated container- mounted piston pump, e.g. for cosmetics, the piston 5 and cylinder 8 have cooperating ports 16, 18, A, E to function as a slide valve controlling intake and delivery of liquid and air, there being no communication between the pump inlet and outlet in the rest position of the pump. The piston may be reciprocable and the cylinder fixed, or vice versa. Actuation may be by press button or trigger. <IMAGE>

Description

15 '20 25 30 35 7894938 ~ 4 _' 2 no other parts are required for controlling the required flow paths. This is done through the guide edges on mutually displaceable openings, as is usual with axial piston valves.

In mechanical engineering, axial piston pumps are known for other applications, which operate without non-return valves. In these, however, either additional parts, such as sliders, are provided for the guide or additional parts are provided for rotating the piston. Such constructions are for cost reasons not usable for such a bulk article as the pump according to the present invention. With the pump according to the invention, these extra parts are omitted, since the piston and the housing only perform a translational movement, ie. a pure displacement movement without rotation of the piston relative to the housing.

The pump according to the invention uses the ambient air for the pumping process. In contrast to conventional pumps, not only the contents (usually liquid) are fed in the intended direction, namely from the container into the open air, but also at each piston stroke air is sucked in from outside into the pump chamber and air and partly also filling into the container. The pump thus operates in a manner which in the case of the conventional pumps should be avoided. However, this achieves important benefits. First and foremost, this enables a very simple construction of the pump. When air is sucked in through the outlet duct, it is further cleaned, which is important especially for sticky and crust-forming products. Furthermore, the connecting duct is cleaned from the container to the pump chamber, and finally air is transported through the pump system back to the container as a replacement for discharged contents. This is in contrast to all known pumps for packaging containers, in which the replacement air always flows past the pump system> into the container.

Since the pump is closed in the outermost piston position and this piston position is normally achieved by means of a return spring, the pump most easily serves in its rest position as a container closure.

Inlet and outlet can be arranged in two fundamentally different ways for the two pump parts, namely the pump piston and the housing.

In pumps of the first type, both are arranged at the same pump part, e.g. at the casing. During the pumping run, the piston is displaced by hand in relation to the housing attached to the container. The outlet nozzle then remains at rest, which is preferable for many areas of use. The same result is obtained by arranging the inlet and outlet at the piston and connecting it to the container. Then the cover is moved by hand in relation to the piston. Even in the container connected nozzle this case, it now remains at rest.

In the case of pumps of the second type, on the other hand, the inlet is arranged at one pump part, for example at the housing, and the outlet at the other part, e.g. at the piston. Here, too, a reversal is possible in such a way that the piston is attached to the container and the housing is actuated by hand. In these cases, the outlet opening is included in the pump movement. Pumps of this type are particularly easy to manufacture. Further developments and advantageous embodiments of the pump according to the invention have the features stated in claims 2-37.

Some embodiments of the invention will now be described in more detail in connection with the accompanying drawing figures.

Figure 1 shows in perspective a packaging container with a hand-driven pump according to the invention.

Figures 1a - 1e are schematic cross-sectional views of the pump of the first type arranged in the container in different phases of a complete piston stroke. Here, inlets and outlets are arranged at the casing.

Figures 2a and 2b are schematic cross-sectional views of a pump of the first type, however, inlets and outlets are arranged in the piston.

Figures 3a - 3c are longitudinal sections through a pump of the first type, in which inlets and outlets are arranged at 7834938-1; the housing, in different phases of a pump stroke.

Figures 4a - 4c show in longitudinal sections and partly in side view a pump of the first type, which is similar to the pump shown in figure 1, in different phases of a pump stroke.

Figures 5a - Sf are schematic longitudinal sections through a pump of the second type, in which the inlet is arranged at the housing and the outlet is arranged at the piston, in different phases of a complete piston stroke.

Figures 5.1 and 5.2 show partly in side view, partly in longitudinal section constructive details in a pump of the second type according to figures Sa - 5f. Figures 5.3 - 5.6 are variants of a pump according to Figures 5.1 and 5.2, which, however, are also important for other embodiments.

Figures 6 and 7 show in longitudinal section two further embodiments of pumps of the second type. Figures 8a and Bb show in longitudinal section and partly in side view an actuating mechanism for a pump according to the invention.

Figure 1 shows a container 1, which is intended for receiving a content, in particular a liquid, which is to be discharged into the open air. The container has a closing hood 3 with a nozzle 9, which for example can be designed as a nozzle. The pump housing (not shown here) is arranged in the closing hood 3, from which a piece of the piston 5 with the control button 6 protrudes.

Figures 1a - 1e show very schematically the design of the pump housing 8 and the piston 5 in detail. The housing has at the bottom an inlet E and at the top an outlet A. In this figure and in the following figures, E and A always denote the openings or wall passages in the housing and in the piston, respectively (Figs. 2a and 2b), the edges of which form guide edges. E and A, on the other hand, do not denote the channels connecting to these openings. The inlet E is connected in a known manner to a small suction pipe 10, which leads into the container 1.

An overflow channel 12 at the top of the piston leads from its end side 14 parallel to the right in the figure to a cavity 15.

In the cavity 15 a compressible medium, for example a sponge with closed pores, can be arranged. The overflow channel 12 is connected by two transverse channels 16 and 18 to the outer wall 19 of the piston. The transverse channel 18 is arranged at the right end of the overflow channel 12 and leads upwards. The transverse channel l6 is arranged longer l0 15 20 25 30 35 40? 8Ü & 938-¿+ (FI to the left and leads downwards.

The above-mentioned guide edges are formed by the edges of the outlet A and the inlet E at the inner wall 211 of the housing and the edges of the transverse channels 16 and 18 at the outer wall 19 of the piston.

Figures 1a - 1e show a suction stroke, when viewed from above and downwards, and a pressure stroke, when viewed from below and upwards.

Figure 1a shows the innermost position of the piston and figure 1e shows the outermost position of the piston. By means not shown, the piston can be pushed out further. In addition, a compression spring (not shown) is provided, which moves the piston to the position shown in Figure 1c, which is consequently the rest position of the pump.

The function description begins with an outward movement from the position according to Figure 1a to the position according to Figure 1e. In the position according to Figure 1a, the transverse channels 16 and 18 are closed. If the piston is displaced to the right, the pump chamber 20 is formed and expanded, respectively, and the transverse channel 18 is connected to the outlet. As a result, air is sucked through the outlet A into the pump chamber 20.

As a result, the nozzle 9, possibly a longer outlet channel arranged between this and the outlet, and the outlet itself from residues stuck therein from a previous pump process are cleaned. When the piston 5 continues to move to the right, the transverse channel 18 is closed (figure 1c), while the transverse channel 16 is still closed. In the embodiment according to Figure 1c, this case is only during a vanishingly small impact area. However, the transverse channels as well as the inlet and the outlet can also be arranged in such a way that both transverse channels remain closed during a considerable displacement distance. In this case, a negative pressure is produced in the pump chamber 20 at the outward movement of the piston (and at the inward movement, which will be described later, an overpressure).

When the piston continues to move to the right, the transverse channel 16 is connected to the inlet E, while the transverse channel 18 remains closed. Liquid is now sucked into the pump chamber through the small suction pipe l0. If a negative pressure has previously been formed in the pump chamber, this is done in a shock-like manner. When the piston has reached its rest position (figure 1e), both transverse channels are closed again. Inlet E and outlet A are also closed in relation to the pump chamber 20. The rest position is also the transport position of the pump. In this position, both the contents of the container 10 and the contents of the pump chamber 20 are sealed from the outlet. The outlet was previously freed from liquid in the phase according to Figure 1b. In the position according to figure 1e, therefore, no liquid escapes from the pump and the container during transport of the unit. The pump chamber 20 is only partially filled with liquid 23. In the horizontal position, the liquid level is below the mouth of the overflow channel 12 at the end side 14 of the piston. When the piston is pushed in from the position shown in figure 1e, the contents of the pump chamber 20 and the channels are first compressed, until the transverse channel 16 opens towards the inlet E. From this moment air and possibly some of the liquid from the pump chamber 20 is forced through the channels l2 and l6 through the inlet E and the small suction pipe l0 back into the container. This cleans the entire intake duct. Above all, small parts, which have been collected in tight spaces and plugged in the suction line, are fed back to the container (figure 1b). After the transverse channel 16 has been closed during further insertion of the piston (figure 1c) and before the transverse channel 18 is opened towards the outlet A, an overpressure is generated in the pump chamber. While the wall opening of the transverse duct 18 extends over the outlet A fi igur lb), the contents of the pump chamber are expelled through the outlet A. Finally, the transverse duct 18 is closed (figure 1a).

The embodiment according to figure 1 also works, if the container is tilted, so that its longitudinal axis lies horizontally and the control button 6 is at the top. 'If the pump goes through any pump processes, it always remains ready for use. In the resting state according to Figure 1e, the pump chamber contains liquid, and when the piston is pressed, liquid is immediately dispensed. This also applies to the following embodiments.

The volume of liquid expelled from the container must usually be replaced by an equal volume of air if the container is not to be compressed. In the embodiment according to Figure 1, there is no direct connection from the outlet to the inlet in any phase. However, as described above, in the phase according to Figure 1d, before the start of an expulsion process, air is first forced through the inlet into the container. This serves to compensate for the liquid discharged during the previous pumping process.

Figures 2a and 2b show, like figures 1a - lee, a pump of the first type. Here, too, the inlet E and the outlet are once put into use, arranged at the same pump part, but in this case in the piston 205 instead of in the housing.

Here, as in the following figures, the last two digits of all the reference numerals denote the same constituents throughout. The first number indicates the figure, ie the 200 series refers to figure 2, the 300 series to figure 3, and so on.

The piston 205 can be attached to a container by means of a hood nut 224. The piston 205 has a small outlet pipe 234 with the nozzle 209. From the nozzle an outlet channel 264 leads to the outlet A. The piston has sealing rings 241, 243 and 244. The outlet A lies between the sealing rings 241 and 243. From the inlet E, which lies between the sealing rings 244 and 243, an inlet channel 227 leads downwards. The lower end of the duct is connected to the suction pipe 210.

Here, as in the following exemplary embodiments, it is not the edges of the inlet E and the outlet A that act as guide edges, but the adjacent sealing rings.

A overflow channel 236 is arranged in the housing 208.

In the position shown in Figure 2a, the pump chamber 220 over the overflow channel 236 communicates with the outlet A. If the housing 208 is displaced upwards, which here takes place through the return spring (not shown), air is sucked in through the outlet A until the sealing ring 243 has passed the overflow channel. lower opening 238. When the casing continues to be displaced upwards, liquid is sucked into the pump chamber through the inlet E and the overflow channel 236. If the casing is then manually pushed downwards against the action of the force from the return spring, air and possibly some of the contents through the overflow channel 236, the inlet E and the inlet channel 227 into the container, until the opening 238 of the overflow channel 236 on its way down has passed the sealing ring 243. Thereafter, contents and air are fed out of the pump chamber 220 through the overflow channel and the outlet A.

A direct connection to the outlet A and to the inlet E occurs when the opening 238 moves over the sealing ring 243.

Air can then flow past the sealing ring 243 into the container for leveling the withdrawn contents.

The embodiment according to Figures 3a - 3c again shows a pump of the first type, at which outlets and inlets, however, are arranged in the housing 308. The piston has an operating button 306. A control part 322 is located above the housing 308. The guide member and the housing have outer flanges and are secured by the hood nut 324 to the container mouth.

At the inlet of the housing 308, the downwardly directed inlet channel 326 begins, which leads to the suction pipe 310. From the outlet A, an outlet channel 328 leads upwards in the housing 308, which continues in an outlet channel 329 in the guide part 322.

The piston further has an overflow channel 312, the upper end of which, over the transverse channel 318, communicates with the outer wall of the piston.

The lower part of the transverse flow channel 312 has an extension 332, which receives the reset spring 354.

The upper position of the piston is given by the abutment of its upper end against the bottom plate of the guide part 322 (Figure 3c), and the lower end position of the piston (Figure 3a) is given by the lower edge abutment of the control button 306 against the bottom plate of the guide part 322.

The piston has four sealing rings 341 - 344. The distribution of the sealing rings over the length of the piston and the position of the transverse channel 318 and the positions of the openings E and A is decisive for the function of the pump, as will be described in more detail below in connection with another embodiment.

In the rest position according to Figure 3c, the outlet A is closed by the piston. However, the inlet E communicates with the pump chamber 320.

However, this is harmless, since the transverse channel 318 is closed by the wall of the casing and thus liquid cannot reach the outlet.

The function shall again be described on the basis of the lowest, ie the innermost piston position (Figure 3a). In this position, the pump chamber 320 is connected to the outlet A. When displaced upwards by the piston, suction is first effected through the nozzle 309, the outlet channels 329 and 328 and the outlet A, whereby these parts are freed from liquid. Air and liquid enter the pump chamber 320 through the overflow channel 312. This ceases as soon as the sealing ring 342 exceeds the upper edge of the opening A of the outlet in the upward direction. Then there is a direct connection from the outlet A to the inlet E. The pump chamber is completely closed off to the outside, so that when the piston moves upwards, a negative pressure first develops in the chamber. As soon as upon further movement upwards the sealing ring 344 connects the inlet E to the pump chamber 320, shock-like liquid is sucked out of the container into the pump chamber. The suction process lasts until the piston reaches its 10 15 20 25 30 35 40 780493841; sleep mode according to Figure 3c.

If the piston is depressed, air and possibly some liquid are first fed back to the container, until the lowest sealing ring 344 blocks the connection from the pump chamber to the inlet E (figure 3b). There is now again a free connection from the inlet to the outlet, so that air can penetrate into the container to replace the liquid previously sucked into the pump chamber.

If the piston is pushed further down, the air is compressed in the pump chamber 320, in the expansion 332 and in the channels 312 and 318. As soon as the sealing ring 342 upon further downward movement of the piston makes a connection from the transverse channel 318 to the outlet A, air rushes out. and liquid through the outlet A and the channels in the open air.

Figures 4a - 4c show an embodiment which is similar to the embodiment according to Figures 1a - 1le but is provided with sealing rings. In addition to the sealing rings 441 - 444, an additional sealing ring 440 is provided. At its left end, the piston has an extension or recess 432, which merges into the longitudinal channel 412. From this, a transverse channel 416 leads downwards and a transverse channel 418 upwards. Between the control button 406 and an outlet pipe 452 a compression spring 454 is arranged, which serves for extraction, ie return of the piston to its right end and rest position shown in figure 4c. Parts not shown provide a limitation of the piston stroke in this position.

The function of the embodiment shown in Figures 4a - 4c largely corresponds to the function of the embodiment shown in Figures 1a - 1e. In contrast to the embodiment according to Figures 1a - 1le, however, inlets and outlets are displaced in the axial direction relative to each other. Therefore, the transverse channels 416 and 418 also have a greater mutual distance.

In all the previously described embodiments, the inlet and outlet are located at the pump component connected to the container. Regardless of whether this consists of the housing or the piston, the outlet nozzle 9, 209, etc. remains. during the pumping process at rest, ie it does not move in relation to the container. This is indicated by the name "pump of the first type". Embodiments will now be described, in which only the inlet is arranged in the housing and the outlet is arranged in the piston and as a result follows the piston movement. Therefore, during the pumping process, the nozzle 509, etc. moves in relation to the container. Such embodiments are referred to as "pumps of the second type".

Figures 5.1 and 5.2 show a pump of the second type with a gun-like head. In the right-hand open cylindrical inner cavity 556 of the housing 508, the piston 505 is inserted from the right.

A stop plate 558 inserted in grooves in the housing from below forms a stop for the piston and determines its outermost position. In a downwardly open hollow core 560 in the piston, the helical compression spring 554 is arranged, which pushes the piston to the right to the position shown, i.e. the rest position. At the right end of the piston, a pistol-type finger grip 562 is rigidly attached. The housing 508 is attached to the neck of the container 501 by means of the hood nut 524.

The stop plate 558 has two further functions: it engages with its upper end in the hollow core 560 and thereby prevents a rotation of the piston about its longitudinal axis. In addition, it serves as a counter bearing for the compression spring 554.

As in the exemplary embodiment according to FIG. 3, the piston has four sealing rings 541 - 544. Again, an overflow channel 512 projecting from the end side into the piston is arranged, which through the transverse channel 518 communicates with the upper outer wall of the piston.

Here, however, the transverse channel 518 opens between the sealing rings 542 and 543.

The inlet E again lies in the housing 508, while here, however, the outlet A is arranged in the piston itself and communicates with the nozzle 509 over the outlet channel 530. The overflow channel 512 and the outlet channel 530 are separated from each other by a transverse wall 566. The outlet A lies between the sealing rings 541 and 542.

At the lower side of the inner wall 521 of the housing, a overflow channel 570 is arranged. This arises by inserting a plug 572 from below into a vertical hole. The plug tightly closes this hole outwards but leaves the overflow channel 570 free at the top.

The four sealing rings, the edges of the overflow channel 570 and the edges of the inlet E. serve as guide edges here.

The overflow channel 570 cooperates with the sealing rings 542 and 543, while the two outer sealing rings 541 and 544 provide for the two outer piston seals and never enter the area of the overflow channel. l0 l5 20 25 30 35 40 7804938-1 ll Figures Sa - 5f illustrate significant work phases. Shortly after the piston begins to move outward, the sealing ring 542 strokes across the overflow channel 570 to the right (Figure 5b). In this case, air is sucked from the outlet E, through the overflow channel 570, the transverse channel 518 and the overflow channel 512 into the pump chamber 520. Thereby the nozzle 509, the suction channel 530 and the other mentioned parts are cleaned of liquid from a previous pumping process. As soon as the sealing ring 542 has exceeded the right guide edge on the overflow duct 570 (figure 5d), this suction of external air ceases. The overflow channel is now blocked by the two sealing rings 542 and 543. Thereby the outlet A is closed from the inlet E. If the distance of these sealing rings is greater than the axial length of the overflow channel, a negative pressure is generated in the pump chamber during the outward movement of the piston. and 543 is outside the overflow channel 570. Conversely, an overpressure is generated in this phase upon insertion of the piston. Thereafter, the sealing ring 543 strokes over the overflow channel 570 to the right (Figure Se). In this case, liquid is sucked out of the inlet E through the overflow channel 570, the transverse channel 518 and the longitudinal channel 512 from the container into the pump chamber 520. The suction process continues, after the sealing ring 543 has exceeded the right guide edge of the overflow channel 570, - which when the sealing ring 544 has exceeded the inlet E (figure 5f).

After that, suction takes place directly from inlet E to the pump chamber 520.

When the piston is inserted, the pump positions are traversed in a row from Figure 5f to Figure 5a. In the positions according to Figures Sf and Se, air and partial liquid are fed in the manner described from the pump chamber 520 into the inlet E, until the sealing ring 543 in the direction of the left has exceeded the left guide edge of the overflow channel 570 (Figure 5d). Then compression takes place until the sealing ring 542 in the left-hand direction has exceeded the right guide edge on the overflow channel 570.

Figure 5c shows the actual expulsion process, in which the sealing ring 542 crosses the overflow channel 570.

Liquid and air are expressed from the pump chamber 520 through the transverse channel 518, the overflow channel 570 and the outlet A. Towards the end of this process there is a direct connection between the pump chamber, the inlet and the outlet (Figure 5b). As a result, replacement air can penetrate into the container but nevertheless the expulsion process continues. If the sealing ring 542 has finally exceeded the left guide edge of the overflow channel 570 (Figure 5a), then the outlet A is closed from the pump chamber and the inlet E through the sealing ring 542. The inlet E is above the transverse channel 518 in connection with the pump chamber, which here is reduced to the space in the overflow channel 5l2.

In the rest position according to Figure 5f, the outlet A through the sealing ring 542 is also closed from the pump chamber and the inlet E, while the inlet E is in direct connection with the pump chamber 520. In both end positions the pump thus functions as an external closure for the container.

If the mutual distance between the sealing rings 542 and 543 is greater than the distance between the right guide edge of the inlet E and the left guide edge of the overflow channel 570, then a direct venting of the container is possible, as shown in figure 5b.

Here there is a free connecting road from the outlet A through the overflow channel 570 directly to the inlet. If, on the other hand, the distance between the sealing rings 542 and 543 is less than the distance between the last-mentioned guide edges, then a direct aeration is not possible. The required replacement air is then fed only into the container from the pump chamber 520 in the positions according to Figures 5f, Se and 5b when the piston is inserted. As shown in Figure 5.3, to provide the four sealing rings 541 - 544, a sleeve 574 of elastic material can be provided, which is inserted over a part of the piston 505 ', which consists of hard material.

As can be seen from Figure 5.4, pistons and sealing rings can instead consist of hard material and be covered with an elastic sleeve 575.

A better mixture of air and liquid can be obtained by the embodiment according to Figure 5.5. In the overflow channel 512 of the piston 505 '*' a plug 576 is inserted here, at the outer surface of which a helical channel 578 starting at the top is arranged, which leads from the left to the right end of the plug. In addition, at the underside of the plug, a longitudinal channel 580 is provided, which extends from the left to the right end of the plug.

Figure 6 shows a pump which is to be mounted vertically on a container and which is provided with an actuating actuating button 606 which can be actuated with a finger and a helical compression spring 654 which pushes the piston upwards to the rest position. In the housing 608 a vertically downwardly extending inlet channel 626 is arranged, and in the piston a vertically upwardly extending outlet channel 630 is arranged. The nozzle 609 directs the exiting jet to the side.

A large part of the pump is located under the upper cover plate of the hood nut 624 and consequently projects into the container not shown here. This reduces the total height of the unit consisting of pump and packaging container.

The pump operates in the manner described in connection with Figures 5a - 5f.

If the pump is to be used in an upside-down position, for example for spraying liquid under furniture or for discharging foot powder, the plug 684 and the suction pipe 610 are removed. The lower end of the inlet duct 626 in Figure 6 can be closed by another plug . Corresponding changes for output in the up and down position can also be made in the other embodiments.

Figure 7 shows another embodiment of a pump with a fully depressed piston. The compression spring arranged in the interior of the overflow channel 712 is not shown here. In the embodiment according to Figure 7, the overflow channel 770 and the inlet channel 726 are provided in a simpler way, namely in that the housing is divided into an inner housing 708 and an outer housing 786. Both are insertable into each other under mutual sealing. Between the two housing parts an annular space 788 remains, from which a radial opening in the inner housing forms the overflow channel 770. The inlet channel 726 is formed by an outer longitudinal groove in the inner housing 708. This embodiment operates in the manner described in connection with the figures. Sa - 5f.

Figures 8a and 8b show a pump according to Figure 3, which, however, is operated by means of a trigger arm 887. Figure 8a shows the upper and Figure 8b the lower end position of the piston 805.

At the upper end of the housing 808, a trigger housing 888 is fixedly provided. In this, the trigger arm 887 is pivotally mounted about a shaft 889 fixed in the housing. For converting the pivotal movement of the trigger arm 887 into a vertical piston movement, an angular lever unit 890 is arranged. It consists of a Y-shaped piece of elastic plastic or the like, which has three arms 891, 892 and 893, which are hingedly connected to each other. The outer ends of the arms 891 and 893 are attached to the shutter sleeve 887 and to the piston 805, respectively, while the outer end of the arm 892 abuts an inner corner of the shutter housing. 888. The working method of the angle lever unit is clear from the two figures.

The outlet channel 828 continues in the trigger housing 888 through a tube 829, which leads to the nozzle 809.

The pump according to each of the described embodiments can operate in very different positions. For example, horizontally, vertically and even upside down.

If the diameter of the pump chamber and the piston are made relatively large in relation to the narrow cross-section of the outlet, then with a short piston stroke a relatively large volume of the contents can be discharged. In this case, a device according to Figure 8 with a trigger arm and a mechanical conversion by an angle lever is advantageous.

As with the embodiments according to Figures 1a - 1le, special ring seals can be dispensed with, if the piston over its entire length is sealingly guided in the channel of the housing. However, embodiments with ring seals are more advantageous. There are many known possibilities to provide such ring seals, for example by sealing rings on the piston, as in the embodiments shown, or by sealing rings in the channel of the housing or by ring grooves being arranged in at least one of the two parts, so that they between the ring grooves the remaining parts act as ring seals.

By changing the positions of the ring seals, you can change the ratio between filling or air during expulsion and the magnitude of the overpressure or underpressure that is formed in an impact area.

In the case of pumps with a movable outlet according to Figures 5, 6 and 7, only four ring seals are required. With the piston fully inserted, the ring seals or sealing rings 541, 641 and 741 must seal the overflow channel 570, 670 and 770, respectively, outwards. In the case of a single piston extended to the stop, the ring seals or sealing rings 542, etc. must be located outside the overflow channel 570, so that the outlet is closed off from the pump chamber and the inlet. The distance between the rings 541 etc. determines the minimum length of the inner space 556 of the housing etc.

Positions according to Figure Sd, in which the sealing rings 542 and 543 seal on both sides of the overflow channel 570 and the inlet E 10 are closed by the two sealing rings 543 and 544, lead to the generation of an overpressure or negative pressure in the pump chamber, as long as these seals persist. If the pump chamber were filled exclusively with liquid, then because liquids could not be compressed, each piston movement would be prevented and the pump thereby become inoperable. Thus, if the rings are arranged in such a way that an overpressure or a negative pressure can be generated, then one must ensure that in addition to liquid there is also air in the pump chamber, or one must in some other way provide for a certain elasticity, e.g. by arranging a flexible wall in the housing or the piston or by inserting a compressible solid material, for example a piece of foam with closed cells. Finally, a leakage current of sufficient size can achieve a pressure equalization. the overflow channel 574, etc. must be of sufficient length for a sufficient amount of the contents to be driven from the pump chamber to the outlet by bypassing the sealing ring 542. If the amount discharged is to be increased, this can be done by extending the overflow channel 570. Alternatively For example, the sealing ring 542 can be placed closer to the outer end of the piston, whereby the compression phase before the actual expulsion process is extended and thus the product is driven to the outlet in a bumpy manner during the opening of the overflow channel while reducing the overpressure.

In addition, the following applies: if the given total length of the inner space of the housing is increased by the distance between the rings 542 and 543, etc., then the phase in which an overpressure is generated when the piston is pressed is enlarged. At the same time, however, the actual expulsion time is reduced. The reverse is true for a reduction of the said distance.

If the guide edges are arranged so that the outlet is connected to the pump chamber over a relatively long stroke but the inlet only over a relatively short stroke, the pump feeds a mixture with a relatively large proportion of air and a relatively small proportion of liquid and vice versa.

In the case of pumps according to Figures 1a, 2, 3, 4 and 8, the outlet is arranged immovably in relation to the container. In these embodiments, only three ring seals are required.

Namely, the ring seal or sealing ring 342 etc. can be dispensed with, if the intention is not to produce an over- or under pressure during the pumping process. When the piston is fully inserted, the outer sealing ring 341, etc. must be outside the outlet A; In the case of a piston expressed as the stop, the innermost sealing ring 344, etc. must be outside the inlet E. The mutual distance between the sealing rings 341 and 344, etc., determines the minimum length of the inner space 356 of the housing, etc.

If, on the other hand, the sealing ring 342 is present, it must be ensured through the above-mentioned means that when overpressure or negative pressure is to be produced sufficiently elastic means are provided, which prevent a blocking of the pump by the liquid. The amount of the expelled contents per stroke is determined by arranging the sealing ring 342 and so on. A comparison with Figure 3 shows that in the embodiment according to Figure 4 the sealing rings 440, 444 and 445 and the transverse channel 416 can be dispensed with. If during the pumping process the generation of an overpressure or negative pressure is not desirable, then the ring 442 can also be dispensed with. The sealing ring 445 only prevents a direct connection between the pump chamber 420 and the inlet E at the end of the stop, through which in the rest position of the pump an exchange of filling between the pump chamber and the container is possible.

The channel of the housing and the piston as well as the ring seals must usually be circular but can also deviate from the circular shape and have, for example, an elliptical or polygonal shape. The term "sealing rings" or "ring seals" is therefore intended to include non-circular seals as well.

The design of the pump makes it possible, by changing the positions of the guide edges, to ensure that either a small amount of liquid and a large amount of air or vice versa is discharged. For the production of a liquid mist, discharge of a large amount of air is preferred. If, on the other hand, as much liquid as possible is to be discharged at each stroke, for example in the form of a jet, the pump is arranged for discharging a small amount of air.

The sealing rings can be designed so that they run obliquely towards the front end of the piston, ie towards the pump chamber, so that at the pressure stroke they provide a reliable seal and do not fold down. On some occasions it may be advantageous to let the rings run obliquely backwards instead. By arranging obliquely running sealing rings, the distance between the inner wall of the housing and a piston sleeve, which has the sealing rings, can be reduced. The rings can tilt 45 ° towards the piston shaft and run out into a sharp edge. * V ..___. _ w. «. = - n .._____...._..._.

Claims (37)

A dispensing pump for discharging a product from a container, comprising an outer part (8) and an inner part (5) arranged therein, both parts together delimiting a pump chamber (20) and are linearly movable back and forth relative to each other over a compression stroke from an extended position to a retracted position and through a suction stroke from the retracted position to the extended position, an inlet opening (E) arranged in one of said parts, which communicates with the container inner, and an outlet opening (A) arranged in one of said parts, which communicates with the surrounding atmosphere, and surfaces formed by said parts, cooperating with each other, arranged that in the reciprocating movement of the two parts in turn open and close the inlet opening and the outlet opening during the pumping cycle, so that the product can enter the pump chamber from the container through the inlet opening and be discharged to the environment from the pump chamber through the outlet opening, characterized in that said cooperating surfaces of the two mutually movable parts (5, 8) are arranged to connect the pump chamber (20) to the interior of the container through the inlet opening (E) during the suction stroke while generating a negative pressure difference between the pump chamber and the container. internal, so that the product is transported into the pump chamber from the interior of the container substantially by suction, and during the compression stroke connecting the pump chamber (20) to the environment through said outlet opening (A), so that the product is discharged from the pump chamber to the environment under pressure, together with each other cooperating surfaces on the two mutually movable parts (5, 8) are arranged to provide an aeration of the container for replacement of product removed from the interior of the container to the pump chamber with air, further to open a connection between the pump chamber (part of the suction stroke) 20) and the environment through the outlet opening (A), so that air is sucked into the pump chamber for re n-flushing the outlet port from product, thereby automatically cleaning the pump during each pump cycle and preventing the outlet port from being clogged by product, and further ensuring during each pump cycle a supply of a predetermined amount of air to the pump chamber (20) for discharging product 78949384: 18 | _z. T. "n" (A) during the compression stroke. Llsanxans with air from the pump chamber (20) through the outlet opening Pump according to claim 1, characterized in that the cooperating surfaces of the two mutually movable parts (5, 8) are arranged to open a connection between the inlet opening (E) and the outlet opening (A) during a part of the relative movement between the extended position and the inserted position. Pump according to claim 1 or 2, characterized in that the cooperating surfaces of the two mutually movable parts (5, 8) are arranged to hold both over a part of the range of motion between the extended position and the inserted position both the connection from the outlet opening (A) to the pump chamber (20) is simultaneously closed by the connection from the inlet opening (E) to the pump chamber, so that an overpressure is generated in the pump chamber during the compression stroke and a negative pressure is generated in the "pump chamber" during the suction stroke. A pump according to claim 3, characterized in that an elastically compressible medium is arranged in the pump chamber (20) or in a cavity (15) directly connected thereto. 5. A pump according to claim 4, characterized in that the elastically compressible medium consists of air. 6. A pump according to claim H, characterized in that the elastically compressible medium consists of a piece of sponge or foam plastic with closed cells. 7. A pump according to claim 3, characterized in that it has an elastic wall part adjacent to the pump chamber (20) or in communication therewith. A pump according to any one of claims I - 7, characterized by a resetting spring (354) arranged to act between the two mutually movable parts (305, 308) in the direction of the extended position. l 9 .. Pump according to one of Claims 1 to 8, characterized in that the cooperating surfaces of the two mutually movable parts (5, 8) are arranged to close the outlet opening (A) at the extended position. 78049384: 19 lf. Pump according to any one of claims 1 - r, characterized in that the outer pump part is designed as a cylinder (8) and the inner pump part is designed as a piston (5) axially movable in said cylinder. 11. ll. Pump according to claim 10, characterized in that the inlet opening (E) and the outlet opening (A) are arranged as separate wall openings in the same pump part and open into the interior of the cylinder (5), and in the second pump part an overflow channel (12) is arranged , which, depending on the piston position, connects the inlet opening and / or the outlet opening to the pump chamber (20). Pump according to claim 11, characterized in that the orifices of the inlet opening and the outlet opening are displaced in the axial direction relative to each other. Pump according to claim 11 or 12, characterized in that the inlet and the outlet are arranged in the wall of the cylinder (8) and that the overflow channel (12) runs in the longitudinal direction of the piston (5) and leads from the pump chamber (20) to an opening (18 ) in the outer wall of the piston. lh. Pump according to Claim 13, characterized in that at least three ring seals (3ul, 3u3, 3HH) are arranged between the cylinder and the piston in the axial direction, of which the outer (šul) seals the inner and outer of the cylinder. , the inner (3uH) provides or blocks a connection from the inlet to the pump chamber and in a striking area near the outer position of the piston separates the inlet from the outlet, and an intermediate ring seal (SH3), which in another striking area separates the inlet from the outlet, and that the opening (318) of the overflow channel (312) lies between it and the outermost ring seal. 15. A pump according to claim 1, characterized in that the ring seals are arranged on the piston, that the outer and the inner are arranged at the active outer and inner ends of the piston, respectively, and that the outer ring seal at all piston positions lies outside the wall opening of the outlet . Pump according to Claim 1 'or 15, characterized in that a fourth ring seal (3H2) is arranged on the piston between the opening (318) of the overflow channel (312) and the intermediate ring seal (âuä) and that the fourth ring seal shortens the stroke area within which there is a connection from the outlet (A) to the opening (318) of the overflow channel (312), and enables the generation of an overpressure or underpressure in the pump chamber. Pump according to one of Claims 1 to 16, characterized in that the distance between the inner and the outer ring seal (3H1, 34U) is greater than the distance between the facing guide edges of the wall openings for the inlet and the outlet. Pump according to claim 17, characterized in that for generating a direct aeration path between the outlet and the inlet the intermediate ring seal (3H3) is arranged so that in a striking area in which the inner ring seal (SHH) lies between the wall opening of the inlet and the closed cylinder end, opens a connection from the wall opening of the outlet to the wall opening of the inlet. Pump according to one of Claims 14 to 18, characterized in that the distance between the inner seal and the intermediate ring seal (344, 343) is less than the distance between the facing guide edges of the wall openings for the outlet and the inlet. Pump according to claim 11, characterized in that the overflow channel (12, N12) is connected to a second opening (16, 416) in the outer wall of the piston and that the second opening is offset relative to the first opening ( 18, 418) towards the inner end of the piston. Pump according to claim 20, characterized in that the second opening (416) is located between the inner ring seals (HKH, HHS) and the intermediate ring seal (HU3). A pump according to claim 11 or 12, characterized in that an inlet duct and an outlet duct are arranged in the piston and each leads to an opening in the outer wall of the piston, the two openings being axially displaced relative to each other, that the overflow duct ( 239 runs in the longitudinal direction of the housing from the pump chamber to an opening (238) in the inner wall of the housing and that in a striking area near the innermost piston position the wall opening of the outlet channel communicates with the outwardly facing opening of the overflow channel and in a striking area communicates with this opening, while the second wall opening is closed (Figure 2) 780lr938 ~ l + Pump according to claim 22, characterized in that three ring seals are arranged at the piston, that the wall opening for the inlet lies between the innermost ring seal '(2uN) and an intermediate ring seal (2H3) and that the wall opening for the outlet lies between the outermost ring seal (2Ul) and the intermediate ring seal (Figure 2). 2%. Pump according to claim 10, characterized in that the inlet opening (E) and the outlet opening (A) are arranged as separate wall openings in each of the two pump parts and open into the interior of the cylinder (556) and that in each pump part at least one overflow channel (512, 570) are provided. Pump according to claim 2u, characterized in that one overflow channel (512) connects the pump chamber (520) with a longer opening (518) to the interior of the cylinder and that the second overflow channel (570) connects two arranged in the other pump part and axially offset offsets relative to each other to the interior of the cylinder. Pump according to claim 25, characterized in that the first overflow channel (512) runs in the longitudinal direction of the piston and that its opening (518) to the interior of the cylinder through one of the ring seals (SHZ) of the piston is separated from the wall opening (A) for a outlet channel (530) arranged in the piston. Pump according to claim 26, characterized in that the second overflow channel (570) is arranged in the cylinder. A pump according to claim 27, characterized in that the two openings of this second overflow channel (570) merge into each other. A pump according to claim 27 or 28, characterized in that the second overflow channel (570) in a stroke area connects the opening (518) of the first overflow channel (512) to the wall opening (A) for the outlet (Figure 5c). Pump according to claim 27 or 28, characterized in that the second overflow channel (570) in another stroke area connects the wall opening (A) for the outlet with the wall opening for the inlet (E) (Figure Sb). _ '? l9h938 ~ ¿»22's Pump according to one of Claims 27 to SC, characterized in that the second overflow channel (570) in a second stroke area connects the inlet (E) to the opening (518) of the first longitudinal channel (512) and thus to the pump chamber. (520) (Figure 5e). 32. A pump according to any one of claims 2H - 35, characterized in that at least four ring seals (5H1-SHR) displaced in the axial direction relative to each other are arranged between the cylinder and the piston. Pump according to claim 32, characterized in that in the case of four ring seals arranged on the piston, the innermost ring seal (SHM) and the outermost ring seal (SHI) are arranged near the operative ends of the piston, that the wall opening of the outlet lies between the outermost and an adjacent ring seal (5H2) and that the opening (518) for the first overflow channel (512) lies between the latter ring seal (5U2) and a further ring seal (SHS) arranged between it and the innermost ring seal (SHU). 3H. Pump according to Claim 33 or 33, characterized in that the distance between the outermost and the nearest ring seal (5U1, 543) is greater than the distance between the facing control edges of the wall opening for the inlet and for the overflow channel ( 570). Pump according to one of Claims 32 to 34, characterized in that the distance between the two ring seals (5H2, 543) adjacent to the opening (518) is greater than the distance between the facing control edges on the wall opening (E) of the inlet and on the overflow channel (570). ' Pump according to one of the preceding claims, characterized in that the overflow channel (18, C35) opening into the pump chamber is connected in an upper part of the pump chamber (EC) in the operating position of the pump in such a way that its mouth is at least partially above the product level. . ' A pump according to any one of the preceding claims, characterized in that when feeding liquid under admixture of air and without generating overpressure or underpressure, the ratio of air to liquid in the discharged volume is determined by the length of the stroke areas, in which the connections from the inlet opening to the pump chamber and from the outlet opening to the pump casmer are open.