Suction device

Abstract

A suction device, having a suction unit for generating a suction flow and having a suction-device housing, in which a dirt-collecting chamber is arranged, which has a suction inlet and is flow-connected to the suction unit via at least one filter and a suction-extraction channel arrangement, wherein at least one external-air inlet, which can be closed by an external-air valve, is arranged on the suction-extraction channel arrangement between the filter and the suction unit, wherein the external-air valve has an external-air-valve body for closing the external-air inlet, which external-air-valve body can be moved, by movement of an actuating element along an actuation path. A transmission is arranged between the actuating element and the external-air-valve body, which transmission enables movement of the actuating element.

Claims

1. A suction device having a suction unit for generating a suction flow and having a suction device housing, in which a dirt collecting chamber is arranged, which has a suction inlet and is flow-connected to the suction unit via at least one filter and an extraction channel arrangement, wherein at least one external air inlet, which can be closed by an external air valve, is arranged on the extraction channel arrangement between the filter and the suction unit, wherein the external air valve has an external air valve body for closing the external air inlet, which external air valve body can be moved, by adjusting an actuating element along an actuation path, between a closed position closing the external air inlet and a passage position releasing the external air inlet, in which external air flowing through the external air inlet flows through the at least one filter in the direction of the dirt collecting chamber for cleaning purposes, and wherein a transmission is arranged between the actuating element and the external air valve body, which transmission enables a movement of the actuating element over at least one free travel segment of the actuating path without any effect on the external air valve body and, on an actuating segment of the actuating path of the actuating element, releases the external air valve body for movement from the closed position to the passage position and/or transmits an actuating force of the actuating element acting towards the passage position to the external air valve body.

2. The suction device according to claim 1, wherein the at least one free travel segment of the actuating path comprises or is represented by a free travel segment which extends between a starting position of the actuating element assigned to the closed position and the actuating segment and/or a free travel segment which extends between the actuating segment and an end position of the actuating element which is farthest away from a starting position assigned to the closed position.

3. The suction device according to claim 1, wherein the actuating element and/or the transmission form(s) or comprise(s) an actuating device for moving the external air valve body in the direction of its closed position.

4. The suction device according to claim 1, further comprising an energy storage device for moving the external air valve body into the passage position or the closed position, wherein the energy storage device serves to provide an actuating force actuating the external air valve body towards the passage position or the closed position.

5. The suction device according to claim 4, wherein the energy storage device can be charged at an actuation of the actuating element along the at least one free travel segment and/or wherein it is coupled to a respective actuating component comprising the actuating element and/or the transmission and/or the external air valve body, so that the energy storage device is charged at a movement of the actuating component.

6. The suction device according to claim 4, wherein the actuating element charges the energy storage device when moving along its actuating path, and/or wherein the actuating element is loaded by the energy storage device in the direction of a starting position of the actuating path which is assigned to the closed position of the external air valve body.

7. The suction device according to claim 4, wherein the energy storage device acts on the external air valve body via a power-boosting gear mechanism and/or a bevel mechanism and/or a lever gear mechanism.

8. The suction device according to claim 1, wherein the actuating element can be actuated manually and/or driven by a servomotor forming a part of the suction device.

9. The suction device according to claim 1, wherein the actuating element is located at a top side of the suction device housing remote from a ground during the use of the suction device, and/or wherein the actuating element comprises a manually actuable actuating segment, wherein the actuating segment, for moving the external air valve body in the direction of the passage position, passes through a path in the direction towards the suction device housing and/or in the direction towards a base side of the suction device housing, which is oriented towards a ground or assigned to the ground during a use of the suction device, and/or in that a direction of a force for the manual actuation of the actuating element is oriented approximately vertically during the use of the suction device.

10. The suction device according to claim 1, wherein the actuating element is mounted on the suction device housing slidably by means of a sliding bearing and/or pivotable by means of a pivot bearing.

11. The suction device according to claim 1, wherein the transmission is designed for an instantaneous release of the external air valve body in the direction of the passage position or an instantaneous transmission of the actuating force of the actuating element to the external air valve body in the direction of the passage position.

12. The suction device according to claim 1, wherein the at least one free travel segment or the sum of its parts is at least twice as long as the actuating segment, and/or wherein the actuating path of the actuating element is longer than a closing path of the external air valve body between its open position and its closed position.

13. The suction device according to claim 1, wherein the transmission has a pawl and/or step and/or bevel and/or actuating slide assigned to the actuating segment.

14. The suction device according to claim 1, wherein the transmission comprises a lever gear mechanism and/or a bevel mechanism.

15. The suction device according to claim 1, wherein the transmission is designed for boosting the power of an energy storage device loading the external air valve body in the direction of its closed position.

16. The suction device according to claim 1, wherein the transmission comprises an actuating part, which is designed as an actuating slide and remains stationary relative to the external air valve body on the at least one free travel segment, not being actuated by the actuating element, and which is taken along by the actuating element on the actuating segment for moving the external air valve body into the passage position.

17. The suction device according to claim 1, wherein the actuating element has a driving segment for moving the external air valve body in the direction of the closed position, and/or wherein a driving region of the external air valve body is slidably accommodated in a receptacle of the actuating element.

18. The suction device according to claim 1, wherein the external air valve body is loaded in the direction of its passage position by an application of negative pressure to the suction unit, and/or wherein a side of the external air valve body which faces the dirt collecting chamber is provided for moving the external air valve body in the direction of the passage position.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Embodiments of the invention are explained below with reference to the drawing, of which:

(2) FIG. 1 is a perspective oblique longitudinal section of a first suction device in normal suction mode,

(3) FIG. 2 is a perspective view from above of an external air valve of the suction device according to FIG. 1,

(4) FIG. 3 is the view according to FIG. 1, but directly from the side,

(5) FIG. 4 is the view according to FIG. 3, but in a cleaning mode,

(6) FIG. 5 is a perspective oblique view of the external air valve according to the preceding figures in the closed position in normal suction mode,

(7) FIG. 6 shows a detail from FIG. 5,

(8) FIG. 7 shows the external air valve according to FIGS. 5, 6 on actuation in the direction of a passage position shown in

(9) FIG. 8,

(10) FIG. 9 is a perspective oblique longitudinal section of a second suction device in normal suction mode,

(11) FIG. 10 is a perspective view of an external air valve, shown at an angle from above, of the suction device according to FIG. 9 in the closed position, and

(12) FIG. 11 shows the external air valve according to FIG. 10, but in a passage position.

DETAILED DESCRIPTION

(13) A suction device 10 is, for example, designed as a domestic vacuum cleaner or a workshop vacuum cleaner. A stationary design of the suction device 10 for a central extraction system is possible in principle, however. In terms of its suction device housing and its basic functionality, a suction device 110 according to FIGS. 9 to 11 corresponds to the suction device 10, so that identical references are used for identical components of the suction devices 10, 110. These are explained below in the context of the suction device 10. The suction device 110 is partially provided with components identical to those of the suction device 10, differences of which are identified by reference numbers increased by 100.

(14) In the drawing, the suction device 10 is partially illustrated in a highly diagrammatic manner. At its suction device housing 12, it may have rollers 11, for example, for rolling or placing on a ground.

(15) The suction device housing 12, for example, has a lower part 20 and a cover 24. The lower part 20 can be provided with the rollers 11. A suction inlet 18 is provided on the lower part 20 for the inflow of a suction flow T, i.e. an air flow loaded with dirt, dust or the like, into a dirt collecting chamber 21.

(16) At the suction inlet 18, there is, for example, provided a connecting piece 19 for connecting, in particular for plugging on, a hose 16. At its other end, the hose may be connected or can, for example, be connected to a suction nozzle of a hand-held power tool or the like.

(17) The dirt collecting chamber 21, into which the suction inlet 18 leads, is provided in the suction device housing 12. Between the suction inlet 18 and a suction unit 15 of the suction device 10 for generating a suction flow T, a filter 29 is located for filtering out particles P contained in the suction flow T, so that they are retained in the dirt collecting chamber 21. At a base wall 22 of the suction device housing 12, in particular of the lower part 12, there forms an accumulation of dust or dirt S, for example. The particles P usually fall downwards, i.e. towards the base wall 22, but at least a part adheres to a lateral surface 29A facing the dirt collecting chamber 21, for example to an underside, of the filter 29. In the suction mode of the suction device 10, the filter 29 is therefore gradually contaminated or afflicted by particles P.

(18) On the discharge side, however, the suction flow T is cleaned by the filter 29, so that it forms a clean suction flow T2 in a manner of speaking when flowing via a lateral surface 29B of the filter 29 towards an air outlet 17. The suction unit 15 is connected to the air outlet 17. The air outlet 17 is provided at an extraction channel arrangement 25 located downstream of the filter 29 in terms of the suction flow T.

(19) The suction unit 15, for example, comprises a common suction turbine and an associated drive motor, which is not explained in detail. A suction turbine and a drive motor are obviously suitable for any suction device according to the invention, not only for the suction device 10.

(20) The dirt collecting chamber 21 is bounded by the base wall 22 and by side walls 23. A front side wall 23 is not shown in the sectional views of the drawing. The lower part 20 is covered by a cover 24, which is expediently releasable from the lower part 20, so that dirt collected in the dirt collecting chamber 21 can be removed easily. It would be possible to provide a receptacle, e.g. a filter bag, in the dirt collecting chamber 21. In the cleaning mode, however, such a filter bag is unnecessary, because the filter 29 is cleaned effectively.

(21) The extraction channel arrangement 25 is provided on the suction device housing 12, in particular on the cover 24.

(22) At a cover wall 24A of the cover 24, a holder 27 is provided for the filter 29, for example. The filter 29 is, for example, installed into an opening 24B of the cover wall 24A and closes it, so that the dirt S is held back in the dust or dirt collecting chamber 21. A holder 27 for the filter 29 is preferably provided at the opening 24B.

(23) Next to the filter 29 or at its outer circumference, a side wall or circumferential wall 26 is provided, and above the filter 29 a cover wall 28 of the extraction channel arrangement 25. The circumferential wall 26 and the cover wall 28 may, for example, bound a chamber and/or an extraction channel of the extraction channel arrangement 25, which leads to the air outlet 17.

(24) At the extraction channel arrangement 25 there is provided an external air inlet 30 for scavenging air or external air F, which can flow through the filter 29 against the direction of the suction flow T to push particles P adhering to the filter 29 towards the dirt collecting chamber 21.

(25) Each of the suction devices 10, 110 therefore has an external air inlet 30, through which external air F can flow to clean the filter 29. For closing and opening a respective external air inlet 30, external air valves 35, 135 described below and actuated in different ways are provided.

(26) The external air inlet 30 can be closed by the external air valves 35, 135, wherein these adopt their closed position and the suction flow T flows from the suction inlet 18 through the dirt collecting chamber 21 and the filter 29 towards the air outlet 17 in the normal suction mode of the suction device 10 as shown in FIGS. 1 and 9.

(27) For a cleaning mode, however, the external air inlet 30 is opened by the external air valve 35, 135 adopting its passage position O, i.e. the external air F can enter through the external air inlet 30 and is drawn in, in a manner of speaking, by the vacuum volume or the negative pressure in the dirt collecting chamber 21, whereby the filter 29 is freed of particles P.

(28) The external air valve 35, 135 comprises an external air valve body 37, 137 designed in the manner of or having a valve disc 38, 138. The at least partially disc-shaped external air valve body 37, 137 bears in its closed position L against a valve seat 36 extending around the external air inlet 30. When the external air valve body 37, 137 bears against the valve seat 36, the external air inlet 30 is closed.

(29) At the disc 38, 138 or at the valve seat 36, or at both components, there is expediently provided a seal 39 for tightly closing the external air inlet 30.

(30) The seal 39 advantageously has an additional damping function when the disc 38 or the external air valve body 37, 137 is moved in the direction of the external air inlet 30 into the closed position L and arrives there.

(31) A driving segment 40 for actuation by an actuation assembly 60 projects from the external air valve body 37. The driving segment 40 comprises connecting arms 41, which project from the external air valve body 37 and are connected to a support segment or power transmission segment 42 designed as a bridge 43 or comprising a bridge 43, for example. Projections 46 of the connecting arms 41 are, for example, inserted into receptacles 45 of the bridge 43. The bridge 43 extends between the connecting arms 41.

(32) The bridge 43 is used to move the external air valve body 37 into the closed position L blocking the external air inlet 30 or into the passage position O opening up the external air inlet 30. For this purpose, the driving segment 40 is displaceable by means of a sliding bearing 50 relative to a valve base 31 having the external air inlet 30 or relative to the valve seat 36. The valve base 31 is, for example, provided by the cover wall 28 or located at the cover wall 28.

(33) The bridge 43 can also be designated as a support body, driving body or supporting bridge.

(34) The sliding bearing 50 comprises guide bodies 51. The guide bodies 51 project from the valve base 31, for example in the manner of supports 52 or pillars 52. Between each pair of guide bodies 51, the guide segments 47 of the driving segment 40 are guided in a linear fashion. The guide segments 47 are provided on the bridge 43, for example.

(35) The actuation assembly 60 comprises an actuating element 61, e.g. a slide 62, which is movable relative to the valve base 31 along an actuation axis V. The actuating element 61 is mounted for linear movement on a guide body 53 extending beyond the external air inlet 30 and located on the valve base 31.

(36) The guide body 53 is, for example, supported on the valve base 31 by support arms 54, 55. The support arms 54, 55 project laterally from the guide body 53, which has an oblong shape, in the manner of spiders or expanding feet, for example. In the end regions of the support arms 54, 55, there are provided connecting elements 59, in particular bolts or the like for example, for connecting the guide body 53 to the valve base 31 and/or the cover wall 28.

(37) The guide body 53 has a guide receptacle or guide contour 56, which extends along the actuation axis V and in which the slide 62 or the actuating element 61 is movably accommodated. The actuating element 61 can therefore not move transversely to the actuation axis V, only along the actuation axis V.

(38) The actuating element 61 has a guide contour 63, which is designed as a protruding rib or step, for example, and which engages the guide contour 56 or guide receptacle 56 from behind.

(39) The actuating element 61 is loaded towards its starting position VA shown in FIGS. 1 to 3 by a spring assembly 71, comprising a coil spring for example. The spring assembly 71 is supported on an abutment 57 of the valve base 31. A coil spring of the spring assembly 71 is accommodated in a receptacle 58 of the abutment 57, for example.

(40) The coil spring or spring assembly 71 is supported on the slide 62 or the actuating element 61, for example on an abutment 72. A guide segment 73 for guiding the spring assembly or coil spring 71 projects in front of the abutment 72. The guide segment 73 engages with an interior of the coil spring 71 in the manner of a guide projection, for example. At the same time, a free end section 74 of the guide segment 73 is provided as a stop against the abutment 57, so that the actuating element 61 can move along an actuating path VS between the starting position VA and the end position VE limited by the abutment 57.

(41) The spring assembly 71 forms an energy storage device 70, which is charged while the actuating element 61 is moved from the starting position VA to the end position VE, in order to move the external air valve 35 back from the passage position O into the closed position L. For this purpose, bevels 67, 68, which together from actuating contours of a bevel mechanism 66, are provided on the actuating element 61. A bridge 43 can slide along the bevels 67, 68, and sliding surfaces can be provided for this purpose, for example. In the present case, this movement is indeed facilitated by the fact that rolls 44 capable of rolling along the bevels 67, 68 are provided at the bridge 43. If the slide 62 or the actuating element 61 moves from the end position VE into the starting position VA, the bridge 43 and thus the transmission segment 42 of the external air valve body 37 is accelerated towards the closed position L at a relatively high speed, wherein the external air valve body 37 is moved towards the valve seat 36 while being damped by the seal 39. A gradient of the bevel 68 is slightly flatter than that of the bevel 67, so that the bevel mechanism 66 can apply a stronger force in the direction of the closed position L, i.e. that the external air valve body 37 is moved towards the valve seat 36 with a force which is greater than a force achievable by the bevel 67. In this way, the external air valve 35 is reliably moved into the closed position L by the actuating element 61 in combination with the bevel mechanism 66.

(42) The actuating path of the actuating element 61, however, is considerably longer than a closing path W of the external air valve body 37 between the passage position O and the closed position L, even in the region of the bevel mechanism 66.

(43) In order to make external air valve body 37 capable of moving as instantaneously as possible from the closed position L into the passage position O while facilitating an adequate charge of the energy storage device, the following measures are taken.

(44) Starting from the starting position VA, the actuating element 61 already starts to apply pressure to the coil spring of the spring assembly 71 on a free travel segment VF1 of the actuating path VS if an actuating force B acts on a manually actuable actuating region 69, which is designed as an actuating arm for example.

(45) In the actuating region 69, there may, for example, be provided a gripping piece 69A, which an operator can press comfortably, e.g. with a finger.

(46) On the free travel segment VF1, the external air valve body 37 remains non-actuated, however, i.e. in the closed position L. The driving segment 40, e.g. the bridge 43, remains supported on an actuating part 81 of a transmission 80 holding the external air valve body 37 in the closed position L during the movement of the actuating element 61 along the free travel segment VF1. Two of the rolls 44 are supported on a holding surface 84 of the actuating part 81, for example.

(47) The actuating part 81 comprises a sliding body or slide, for example. The actuating part 81 is mounted at a guide 82 for movement in the direction of the actuation axis V.

(48) The actuating part 81 has a clearance 83, for example, through which the actuating element 61 passes. In the clearance 83, the bevel 67, 68 are located, the bevels 67, 68 being movable relative to the holding surface 84. In this way, the driving segment 60 is optimally supported laterally adjacent to the bevels 67, 68 at mutually spaced points, i.e. the two holding surfaces 84.

(49) The actuating element 61 is movable relative to the actuating part 81 along the actuation axis V, so that the actuating element 61 is movable relative to the valve base 31 along the actuation axis V independently of the actuating part 81 in the free travel segment VF1.

(50) The external air valve body 37 is loaded in the direction of the passage position O by the negative pressure U prevailing in the dirt collecting chamber 21, only remaining in the closed position L because the driving segment 40 is supported on the actuating part 81, or more precisely on its holding surface 84. The negative pressure U is in any case lower than an atmospheric pressure A acting on that side of the external air valve body 37, 137 which is remote from the dirt collection chamber 21.

(51) If the actuating element 61 is moved further towards the end position VE at the end of the free travel segment VF1, is passes through an actuating segment VB, where a driving stop 64 hits the actuating part 81, taking it along towards the end position VE. In this process, the holding surface 84 is pulled away under the rolls 44 in a manner of speaking, wherein the rolls 44 roll along a sloping surface 86 and an adjoining step 85 and instantaneously arrive at a stop face 87, in a downward direction in the drawing, for example. As a result, the external air valve body 37 instantaneously opens up the external air inlet 30, through which external air F or scavenging air then flows on the direction of the filter 29.

(52) The stop face 87 limits the movement of the external air valve body 37 in the direction of the passage position O. A height of the step 85, which could also be described as a release contour, corresponds to the closing path W.

(53) Beyond the actuating segment VB, the actuating element 61 can expediently be moved further in the direction of the end position VE in order to further charge the energy storage device 70. This further tensions the spring assembly 71.

(54) The actuating part 81a slide in a manner of speakingcan be carried along further in the direction of the end position VE in this process and passes through a further free travel segment VF2. During the movement of the actuating element 61 along the free travel segment VF2, the external air valve body 37 remains in the passage position O or at the end of the closing path W, remaining non-actuated. The stop face 87 accordingly extends along the free travel segment VF2.

(55) If the operator releases the actuating element 61, the energy storage device 70 can actuate the actuating element 61 from the passage position O into the closed position L, acting as a return device for the external air valve body 37. In this process, the actuating element 61 already gains momentum on the free travel segment VF2 before the bevel mechanism 66 actively actuates the external air valve body 37 in the direction of the closed position L. At the end of this process, i.e. when the external air valve body 37 bears against the valve seat 36 and the driving segment 40 has been raised so far that the holding surface 84 can be moved under the bridge 43 or the actuating segment 42, a return stop 65 of the actuating element 61 comes into engagement with the actuating part 81, i.e. the slide, taking it along in the direction of the starting position VA, as a result of which the holding surface 83 moves under the bridge 43 or its rolls 44, thereby locating the external air valve body 37 in the closed position L. If applicable, the bevel 86 can be moved past the rolls 44 in this process in order to actuate the external air valve body 37 in the direction of the closed position L with an appropriate actuating force and/or to facilitate a movement of the holding surface 83 under the bridge 43.

(56) It can be seen that in the embodiment shown in FIGS. 1 to 8 an actuating force could act tangentially to the suction device housing 12, so that an operator would have to support the latter, for example against rolling away. It is, however, simply possible to provide a diverting mechanism between the actuating element 61 and the external air valve 35, for example, so that the operator could apply an actuating force towards a ground on which the suction device 10 is placed.

(57) As an alternative or in addition, a servomotor 88 could be provided for moving the actuating element 61 along the actuating path VS (shown diagrammatically in FIG. 7). The servomotor 88 could, for example, have a pinion meshing with a rack section at the actuating element 61. The servomotor 88 could, for example, be motion-coupled to the actuating element 61 in the direction of the end position VE, but have free travel in the direction of the starting position VA.

(58) In the embodiment shown in FIGS. 9 to 11, an actuating force B is advantageously oriented towards a ground or a base side of the suction device housing 12, so that in this case, too, an appropriate actuating force B can be applied to an actuating element 161 by means of a suitable actuator or servomotor 288, but manual operation by an operator is easy as well.

(59) The servomotor 288, for example, has an actuator 289 capable of linear movement for applying the actuating force B. The servomotor 288 may be a pneumatic drive, an electric linear drive or the like, for example.

(60) The external air valve body 137 of the external air valve 135 has a driving segment 140, which can be actuated in the region of a transmission segment 142 by an actuation assembly 160. The external air valve body 137 is likewise loaded towards the passage position O by the negative pressure U, is however held in the closed position L by the actuation assembly 160.

(61) From the external air valve body 137, an actuating projection 141 passing through a driving receptacle 156 of the actuating element 161 projects in the manner of a peg, for example. The actuating element 161 comprises an actuating lever 162, which is pivotably mounted on a pivot bearing 150.

(62) The pivot bearing 150 comprises a bearing block 152, for example, which projects from the valve base 31. A bearing bolt engaging with a bearing receptacle 151 in an end region of an arm segment 167 of the actuating lever 162 is held on the bearing block 152, for example.

(63) With the actuating lever 162, which forms a part of a lever mechanism 166, the external air valve body 137 can be actuated from the passage position O into the closed position L.

(64) The driving receptacle 156 is located between the arm segment 167 and a further arm segment 168, in the end region of which an actuating region 169 for gripping or operation by an operator is provided.

(65) If the actuating lever 162 moves away from the external air inlet 30, a head 143 is supported in the free end region of the actuating projection 141 on that side of the actuating lever 162 which is remote from the external air valve body 137, so that the actuating lever 162 carries the external air valve body 137 along into the closed position L. The lever arm of at least the arm segment 167 forms a lever mechanism 166, which actuates the external air valve body 137 in the direction of the closed position L for the purpose of a power boost.

(66) The actuating element 161 is loaded by an energy storage device 170 towards a starting position VA assigned to the closed position L. The energy storage device 170 comprises a spring assembly 171, e.g. a coil spring. The spring assembly 171 is supported on an abutment 157 relative to the valve base 31 with the external air inlet 30 on the one hand and on the arm segment 168 on the other hand. There, a receptacle 173 for the spring of the spring assembly 171 is provided, for example. On the side of the valve base 31, there is provided a receptacle 158 for the spring of the spring assembly 171, for example. As a result, the energy storage device 170 or the spring assembly 171 acts on the actuating lever 162 in the end region thereof which is remote from the pivot bearing 150, with the effect of a power boost. This contributes to the fact that a relatively great force, in any case a boost for an actuating force of the energy storage device 170, is applied to the external air valve body 37 in the direction of the closed position L.

(67) The actuating region 169 pivots about the pivot axis of the pivot bearing 150. The energy storage device 170 or the spring assembly 171 respectively can be charged or tensioned respectively along almost the whole of the pivoting path of the actuating region 169, which represents an actuating path VS. In this process, the actuating element 161 passes, starting from the starting position VA, first a free travel segment VF1, in which the spring assembly 171 is tensioned but the external air valve body 37 remains in the closed position L, i.e. is not released. This movement can be seen if FIGS. 9 and 10 are viewed together, for example. In this process, the driving receptacle 156 moves along the driving segment 140, so that the head or peg 143 is released from the actuating lever 161, i.e. projects in front thereof (see FIG. 10). The spring assembly 171 is already being tensioned.

(68) On a further actuating segment VB of the actuating path VS, which adjoins the free travel segment VF1, an actuating projection 163 comes into engagement with an actuating part 181 of a transmission 180. The actuating part 181 comprises a slide, for example, which is mounted on a guide 182 for movement relative to the valve base 31. The slide or actuating part 181 has a holding projection or holding segment 184, which in the position according to FIGS. 9 and 10 is in engagement or in engagement from behind with a holding surface 144 provided on the driving segment 140. As long as the holding segment 184 or the actuating part 181 is in engagement with the holding surface 144, the external air valve body 37 cannot enter the passage position O. The holding surface 144 is, for example, provided on a holding projection 147 projecting from the driving segment 140 or the actuating projection 141.

(69) The actuating part 181 is rod-shaped. It is, for example, accommodated in a guide receptacle 183 of a bearing element 185 and capable of movement along the actuation axis V, so that it can be disengaged from the holding surface 144.

(70) The actuating part 181 is, for example, loaded by a spring assembly 186, e.g. a coil spring, into the holding position holding the driving segment 140 and thus holding the external air valve body 37 in the closed position L, i.e. towards engagement with the holding surface 144. The spring assembly 186 is supported on an abutment face 187 at one end, for example. The abutment face 187 is, for example, provided in an end region opposite to that with the holding segment 184. At the other end, the spring assembly 186 is, for example, supported on a support surface 188 of the valve base 31, e.g. at the outer circumference of a cylindrical surface provided with the receptacle 158.

(71) To actuate the actuating part 181 into a release position, i.e. to disengage it from the holding surface 144, an actuating projection 163 is provided on the actuating element 161. The actuating projection 163 engages with a driving receptacle 189 of the actuating part 181. If the actuating element 161 is actuated from the starting position VA in the direction of the end position VE, a driving contour 164 acts against a stop region or longitudinal end region of the driving receptacle 189 to move the actuating part 181 away from the holding surface 144 or the driving segment 140, thereby releasing the external air valve body 137, so that it moves towards the passage position O under the action of the negative pressure U. This happens instantaneously, because in principle the external air valve body 137 is unlatched from the closed position L in a manner of speaking.

(72) The external air valve body 137 hits the actuating element 161 with the head 143 in the passage position O.

(73) For moving from the passage position O to the closed position L, the energy storage device 170 acts once again as described above. To enable the actuating part 181 to pass the holding projection 147, an actuating chamfer 146 having an inclination for moving the actuating part 181 into the release position is provided thereon. The actuating part 181 preferably slides along the actuating chamfer 146 with a chamfer 190. This provides for a bevel mechanism or a wedge gear mechanism for actuating the actuating part 181 when moving the external air valve body 137 or the driving segment 140 in the direction of the closed position L. It is, however, also possible to provide that a return contour 165, for example, hits the actuating projection 163 on the driving receptacle 189, thereby actuating the actuating part 181 in the direction of the release position if the actuating element 161 pivots in the direction of the starting position VA.

(74) It is obvious that between the end position VE and the actuating segment VB a further free travel segment not shown in detail in the drawing can be provided in order to charge the energy storage device 170 further or to tension the spring assembly 171 more tightly, so that the force for returning the external air valve body 137 into the closed position L is correspondingly greater.

(75) The possibility of the active actuation of the external air valve body 137 in the direction of the passage position O, for example by means of an actuating projection 263 on the actuating element 161, is indicated diagrammatically only. This variant can, for example, support the actuation of the external air valve body 137 by negative pressure U or, in embodiments where of the external air valve body is held in the closed position by negative pressure, open the external air valve body by applying a suitable actuating force to the external air valve body in the direction of the passage position O.

(76) In place of the slidable actuating parts 81, 181, a pivotable component could be provided, for example a hook engaging the bridge 43 or the holding surface 144 from below and capable of being diverted into a disengagement position or release position by the actuating elements 61, 161 on the actuating segment VO.