OVERPRESSURE VALVE FOR A DOOR DRIVE

Description

[0001] The invention relates to a pressure relief valve for a door drive, in particular for a door closer, a door drive, in particular a door closer with such a pressure relief valve, and a method for manufacturing such a pressure relief valve, according to the preamble of claim 1.

[0002] Conventional pressure relief valves for door drives, and especially for door closers, comprise, and in particular consist of, four main components: a housing, a sealing element, a spring element, and a bearing element. The housing contains a flow channel formed within it. The sealing element is movable within the housing between a closed position, in which it closes the flow channel, and an open position, in which it releases the flow channel. The bearing element, in particular like the sealing element and the spring element, is inserted axially into a receiving area of ​​the housing and fixed within the housing. The spring element is clamped within the housing between the bearing element and the sealing element in such a way that it biases the sealing element from its open position to its closed position.

[0003] The resulting preload force for the sealing element defines the response pressure of the pressure relief valve and depends significantly on the specific position in which the bearing element is fixed within the housing.

[0004] According to a conventional approach, the bearing element is fixed within the housing using a retaining clip. An example of such a clip is shown in FIG. 3 shown.

[0005] The in FIG. 3The pressure relief valve 1 shown, according to the prior art, is formed from a housing 3, a sealing element 5, a spring element 7, and a bearing element 9. In contrast to the embodiment according to the invention described below, the housing 3 here has several recesses 3c. The bearing element 9 has clip contours or forms 9c. To assemble this pressure relief valve 1, the bearing element 9 is inserted axially into a receiving area 3a of the housing 3 after the sealing element 5 and after the spring element 7, until the clip contours or forms 9c of the bearing element 9 engage in the recesses 3c of the housing 3. The relative position between the bearing element 9 and the housing 3 depends on the specific positioning of the recesses 3c in the housing 3 and the clip contours or forms 9c on the bearing element 9.Consequently, the force with which the sealing element 5 is biased into its closed position by the spring element 7 is already determined before the individual components 3, 5, 7 and 9 are assembled. This also applies to the response pressure of the resulting pressure relief valve 1. Compensation for any manufacturing tolerances is no longer possible.

[0006] However, it has been shown that with such a design, even small tolerance variations in the manufacture of the individual components 3, 5, 7 and 9 of the pressure relief valve 1 can lead to relatively large fluctuations in the obtained response pressure.

[0007] DE 10 2009 057 327 A1 discloses a check valve with a housing in which an insert with a movable actuating element is provided, which is designed to close a passage through the housing past the insert in a spring-force-dependent manner, wherein the housing has a bend in the region of a first end opposite the actuating element, which forms a stop for the insert. The bend is designed as a rolling contour, wherein the first end of the housing is less than five times the wall thickness away from the bend.

[0008] DE 90 07 022 U1 discloses a valve, in particular for bypassing a lubricating oil filter of an internal combustion engine, comprising a valve plate, a valve seat interacting with the valve plate, a valve spring, and a valve cap, wherein the valve spring is supported against the valve cap and exerts a force on the valve plate to seal the opening between the valve plate and the valve seat, wherein the valve body has a crimped edge on the end face facing the valve seat, to which the valve cap is crimped. The valve seat is arranged on the conical surface of a central bore of a valve body, wherein the valve plate also has a conical surface that abuts the conical surface of the bore, and wherein the valve body is a cylindrical body and has a screw thread on its outer circumference.

[0009] DE 90 10 459 U1 discloses a valve, in particular for bypassing a lubricating oil filter of an internal combustion engine, with a valve plate similar to the valve from the aforementioned document, wherein the valve hood has a circumferential flanged edge and recesses are provided above the flanged edge, which are evenly distributed over the circumference of the valve hood, wherein a cylindrical guide is provided at the upper end of the hood, wherein the valve plate contains a bore closed on one side, which faces the cylindrical guide and into which the cylindrical guide extends.

[0010] DE 43 26 968 U1 discloses a locking device for locking objects that are movable relative to each other, e.g. for doors, wherein two throttling points are connected in series between two working chambers in the locking device.

[0011] In light of this, it is an object of the present invention to provide a pressure relief valve for a door drive in which the specified response pressure is obtained simply and, above all, reliably.

[0012] This problem is solved by a pressure relief valve for a door drive with the features of claim 1. Advantageous embodiments of such a pressure relief valve are described in the dependent claims. Furthermore, the present invention also relates to a door drive with such a pressure relief valve and to a manufacturing method for obtaining such a pressure relief valve.

[0013] In the pressure relief valve according to the invention, the bearing element is fixed in the housing by means of at least one plastic deformation of the housing. The plastic deformation positions and fixes the bearing element in the housing in such a way that the sealing element is pre-tensioned into its closed position by the spring element with a predetermined force.

[0014] According to the invention, the bearing element is not fixed to the housing in a fixed, predetermined relative position. Rather, the bearing element is fixed at precisely the relative position that results in the necessary preload force of the sealing element for the desired response pressure. This makes it possible to compensate for tolerances occurring during the manufacture of the individual components of the pressure relief valve by adjusting the selection of the specific relative positioning of the bearing element within the housing during assembly of the pressure relief valve. This is achieved in a particularly simple manner, namely by adjusting the position of the respective plastic deformation of the housing along the receiving area of ​​the housing. Plastic deformation, in this context, refers to an actual deformation or reshaping of the housing.A mere recess or a specific, predetermined shape of the housing, as is the case, for example, with the design described above according to the prior art, does not fall under the term "deformation" as it is understood here.

[0015] According to the invention, the bearing element has at least one recess in a radial outer circumference, and the at least one plastic deformation of the housing projects into the at least one recess to define an axial relative position of the bearing element with respect to the housing. In particular, the respective plastic deformation and the respective recess form a positive fit. This is a particularly simple and reliable way of fixing the bearing element in the housing.

[0016] Preferably, the bearing element has at least two separate recesses of this type, while the housing has at least two separate corresponding plastic deformations. Each of the plastic deformations projects into one of the separate recesses. The formation of multiple pairs of recess and corresponding deformation results in a more reliable and secure fixation of the bearing element in the housing.

[0017] Particularly preferred are the separate recesses in the bearing element and the corresponding separate plastic deformations of the housing, evenly distributed around the radial outer circumference of the bearing element. This prevents the bearing element from tilting within the housing, which in turn counteracts fluctuations in the response pressure of the pressure relief valve.

[0018] Preferably, the separate recesses in the bearing element and the corresponding separate plastic deformations of the housing are arranged in pairs opposite each other around the radial outer circumference of the bearing element. In other words, each pair of recess and its corresponding plastic deformation is paired with a corresponding pair of recess and its corresponding deformation. This facilitates the manufacture of corresponding pressure relief valves and reduces the risk of retaining undesirable stresses in the housing during the formation of the respective deformations.

[0019] Preferably, the bearing element has a sleeve section that at least partially surrounds the spring element transversely to its longitudinal direction. This allows for a particularly compact yet stable design of the pressure relief valve.

[0020] Preferably, the respective recess(s) are formed by a respective opening in the sleeve section of the bearing element. Such openings are easy to form and allow the respective deformations to be created through the entire wall of the sleeve section. This enables a particularly precise and reliable fixation of the bearing element within the receiving area of ​​the housing.

[0021] Preferably, the bearing element is designed such that it is continuously displaceable within the housing in the axial direction of the receiving area before the formation of at least one plastic deformation of the housing. In other words, the bearing element is designed such that its relative positioning within the housing can be selected continuously, i.e., over a continuous range of relative positions. This allows for particularly precise adjustment of the resulting preload force and thus the opening pressure of the pressure relief valve during its formation.

[0022] Preferably, apart from the plastic deformation(s) formed, no further fixing is provided between the bearing element and the housing. Thus, only the plastic deformation(s) formed serve to fix the bearing element within the housing. Such a design is particularly simple and cost-effective to produce.

[0023] Alternatively, in addition to the plastic deformation(s) formed, at least one further fixing point between the bearing element and the housing is preferably provided. This means that, in particular, after the formation of the plastic deformations and thus after a pre-fixation of the bearing element within the housing, at least one further fixing point of the bearing element to the housing is formed. This enables a particularly reliable fixing of the bearing element at the respective relative position within the housing.

[0024] Preferably, at least one additional fixing is achieved by welding the housing to the bearing element. In particular, this involves laser welding of the housing to the bearing element. Such additional fixings are relatively easy to create and ensure a particularly reliable fixing of the bearing element.

[0025] Another aspect of the present invention relates to a door drive, in particular a door closer, with at least one of the previously described pressure relief valves. With such a door drive, one can benefit from the advantages gained through the respective pressure relief valve.

[0026] A further aspect of the present invention relates to a method for manufacturing a pressure relief valve for a door drive, in particular for manufacturing a pressure relief valve for a door closer. In particular, the present invention relates to a method for manufacturing one of the pressure relief valves described above.Conventional manufacturing processes regularly include at least the following steps: providing a housing with a flow channel and a receiving area formed therein; inserting a sealing element and a spring element into the receiving area of ​​the housing such that the sealing element is movably positioned in the housing between a closed position, in which it closes the flow channel, and an open position, in which it releases the flow channel; positioning a bearing element in the receiving area of ​​the housing such that the spring element is clamped between the sealing element and the bearing element in such a way that it preloads the sealing element from its open position to its closed position.The fixing of the bearing element within the housing is achieved by forming at least one plastic deformation of the housing at a position in which the sealing element is pre-tensioned into its closed position by the spring element with a predetermined force.

[0027] As explained above, according to the invention, the bearing element is not fixed at a relative position in the housing defined by previously formed recesses in the housing. Rather, according to the invention, the fixing is achieved by forming at least one corresponding deformation of the housing, specifically at the relative position in which the predetermined preload force for the sealing element, corresponding to the desired response pressure, is obtained. This allows for the simple and reliable compensation of any tolerances in the manufacture of the individual components of the pressure relief valve during its assembly.

[0028] Preferably, when assembling the pressure relief valve, the bearing element is inserted into the receiving area with a force corresponding to the specified preload force against the force of the spring element, and the bearing element is fixed in the resulting relative position to the housing by the formation of at least one plastic deformation. This method is particularly easy to implement and enables reliable fixing of the bearing element in the corresponding relative position.

[0029] Before positioning the bearing element in the receiving area, at least one recess is formed in a radial outer circumference of the bearing element, according to the invention. The at least one plastic deformation of the housing is then formed such that it projects into the at least one recess, thereby defining an axial relative positioning of the bearing element with respect to the housing. In particular, the plastic deformation and the respective recess form a positive fit. Such a procedure is particularly simple and therefore also cost-effective.

[0030] Preferably, at least two separate recesses of this kind are formed in the radial outer circumference of the bearing element, and at least two separate plastic deformations are formed in the housing such that each of the plastic deformations projects into one of the separate recesses. The formation of several pairs of recess and plastic deformation enables a particularly reliable and positionally accurate fixation of the bearing element in the housing.

[0031] Preferably, the separate recesses in the bearing element and the plastic deformations of the housing are formed evenly distributed around the radial outer circumference of the bearing element. This enables a particularly stable and reliable overall design for the pressure relief valve.

[0032] Preferably, the separate recesses in the bearing element and the deformations of the housing are each formed in pairs opposite each other, distributed around the radial outer circumference of the bearing element.

[0033] Preferably, at least one plastic deformation of the housing is formed by means of a conical die. Such formation of the at least one plastic deformation is particularly simple and enables a particularly reliable fixing of the bearing element.

[0034] Preferably, in addition to the plastic deformation(s) formed, no further fixing is formed between the bearing element and the housing.

[0035] This simplifies the manufacturing process and saves costs.

[0036] Alternatively, in addition to the plastic deformation(s) already formed, at least one further fixing point is preferably created between the bearing element and the housing. This results in a particularly reliable and durable fixing of the bearing element.

[0037] Preferably, at least one additional fixing is achieved by welding, in particular by laser welding, the housing to the bearing element. Such an additional fixing is relatively easy to create and yet reliable and durable.

[0038] The invention is described below by way of example with reference to the accompanying drawings. It shows, FIG. 1 an exploded view of an exemplary pressure relief valve according to the invention; FIG. 2 A sectional view of the pressure relief valve made of FIG. 1 during the assembly of the pressure relief valve; and FIG. 2 Legs sectional view of the pressure relief valve made of FIG. 1 during the formation of the deformations to fix the bearing element in the housing.

[0039] Now, with reference to the Figure 1 , 2A and 2B An embodiment of a pressure relief valve 1 according to the invention is described.

[0040] The pressure relief valve 1 shown essentially consists of a housing 3, a sealing element 5, a spring element 7 and a bearing element 9.

[0041] As especially in the Figures 2A and 2B As can be seen, a flow channel 4 is formed in the housing 3. This runs from an inlet 4a to at least one outlet 4b. The sealing element 5 is inserted into a receiving area 3a of the housing 3 such that, in a closed position, it closes the flow channel 4 (see FIG. 2A and FIG. 2B ).

[0042] In the embodiment shown, two opposing outlets 4b are formed for the flow channel 4. However, the specific design of the flow channel 4 and the sealing element 5 is not limited to this variant. For example, only one outlet 4b can be formed, which is then provided, in particular, at the end of the receiving area, as is the case in the FIG. 3 The illustrated design is the case.

[0043] The only important requirement is that the bearing element 9 is inserted axially into the receiving area 3a of the housing 3 and is fixed in the housing 3, and that the spring element 7 is clamped between the bearing element 9 and the sealing element 5 within the housing 3 in such a way that the spring element 7 pre-tensions the sealing element 5 into its closed position. The sealing element 5 must be able to move from the closed position to an open position, in which the sealing element 5 releases the flow channel 4, against the pre-tension force of the spring element 7.

[0044] This movement into the open position is caused by a pressure medium which enters the flow channel 4 through the inlet 4a and, at sufficient pressure of the medium, the so-called response pressure, exceeds the preload force of the spring element 7. Thus, the pressure relief valve 1 allows the pressure medium to flow out through the at least one outlet 4b as soon as the pressure of the pressure medium at the inlet 4a exceeds the response pressure. The magnitude of the response pressure depends essentially on the force with which the spring element 7 preloads the sealing element 5 into its closed position.

[0045] To ensure that the desired response pressure is reliably maintained despite certain tolerances in the manufacture of the individual components 3, 5, 7 and 9 of the pressure relief valve 1, the bearing element 9 is fixed within the housing 3 by means of at least one plastic deformation 3b of the housing 3. This deformation is only formed during the assembly of the pressure relief valve 1. As shown in particular in FIG. 2BAs shown, in the present embodiment, two opposing plastic deformations 3b are formed, each extending into a corresponding recess 9a in the bearing element 9. The deformations 3b and the corresponding recesses 9a form a positive fit, blocking any movement of the bearing element 9 relative to the housing 3. To achieve the desired response pressure for the pressure relief valve 1, the bearing element 9 is pushed into the receiving area against the force of the spring element 5 with a force corresponding to the preload required for the respective response pressure. This is shown in FIG. 2A as shown. As soon as the bearing element 9 has reached its relative position in the housing 3 corresponding to the respective insertion force, the corresponding plastic deformations 3b of the housing 3 are formed.

[0046] In practice, this can be achieved, for example, by clamping the housing 3 in a fixed position and pressing the bearing element 9 into the receiving area 3a with the specified force using an insertion device (not shown). The insertion device comprises a number of forming tools corresponding to the number of deformations to be created. These forming tools are positioned at the level of the recesses 9a of the bearing element 9 and, as the bearing element 9 is inserted, move along the outside of the housing 3 together with the respective recesses 9a. Upon reaching the insertion position corresponding to the respective insertion force, the forming tools are activated to create the respective plastic deformations 3b of the housing 3. The resulting plastic deformations 3b always project into the corresponding recesses 9a. Preferably, the plastic deformations 3b are formed by conical punches.

[0047] This procedure makes it possible to fix the bearing element 9 to the housing 3 in a simple and reliable manner at the relative position corresponding to the specified preload force.

[0048] To increase the stability of the formed pressure relief valve 1, the individual recesses 9a in the bearing element 9 and the corresponding deformations 3b of the housing 3 are or are evenly distributed around the radial outer circumference of the bearing element 9 and in particular arranged in pairs opposite each other.

[0049] To improve the retention of the spring element 7, the bearing element 9 has a sleeve section 9b which at least partially surrounds the spring element 7 transversely to its longitudinal direction. The described recesses 9a are formed as openings in the aforementioned sleeve section 9b.

[0050] However, other configurations for fixing the bearing element 9 to the housing 3 are also possible. In particular, it is also conceivable to design the bearing element 9 as a self-contained piston element and / or to form the recesses 9a merely as indentations on the outer circumference of the bearing element 9.

[0051] In this context, a particularly advantageous embodiment has been identified in which the bearing element 9 is continuously displaceable within the housing 3 in the axial direction of the receiving area 3a of the housing 3 before the formation of at least one plastic deformation 3b of the housing 3. In other words, preferably the relative position of the bearing element 9 with respect to the housing 3 can be freely selected over a continuous range of relative positions.

[0052] The plastic deformations 3b formed can serve to fix the bearing element 9 to the housing 2, and no further fixings can be or will be formed, as is the case in the embodiment shown here.

[0053] If required, which is particularly the case for planned applications involving relatively high pressures, at least one additional fixing point between the bearing element 9 and the housing 3 can be provided, in addition to the plastic deformations 3b already formed. An example of such an additional fixing point is welding, in particular laser welding, of the housing 3 to the bearing element 9.

[0054] The pressure relief valve 1 shown here is further equipped with a sealing ring 11, which, after the pressure relief valve 1 has been inserted into a corresponding door drive, enables a tight seal between the pressure relief valve 1 and the other components of the door drive.

[0055] The present invention relates not only to such a pressure relief valve 1, but also to a corresponding manufacturing method as well as a door drive and in particular a door closer with such a pressure relief valve 1. Reference symbol list

[0056] 1 Pressure relief valve 3 Housing 3a Receiving area 3b Deformation 3c Recess 4 Flow channel 4a Inlet 4b Outlet 5 Sealing element 7 Spring element 9 Bearing element 9a Recess 9b Sleeve section 9c Clip contour or shape 11 Sealing ring

Claims

1. Overpressure valve (1) for a door drive, in particular for a door closer, wherein the overpressure valve (1) comprises: a housing (3) with a flow channel (4) formed therein; a sealing element (5) which is provided in a manner movable between a closed position, in which it closes off the flow channel (4), and an open position, in which it opens up the flow channel (4), in the housing (3); a spring element (7); and a mounting element (9) which is inserted in an axial direction into a receiving region (3a) of the housing (3) and is fixed in the housing (3); wherein the spring element (7) is clamped within the housing (3) between the mounting element (9) and the sealing element (5) in such a way as to preload the sealing element (5) from its open position into its closed position, wherein the mounting element (9) is fixed in the housing (3) via at least one plastic deformation (3b) thereof, and, via the at least one plastic deformation (3b), the mounting element (9) is fixed at that relative position in the housing (3) in which the spring element (7) preloads the sealing element (5) into its closed position by way of a predefined force, characterized in that the mounting element (9) has at least one cutout (9a) in a radial outer circumference of the mounting element (9), and the at least one plastic deformation (3b) of the housing (3) projects into the at least one cutout (9a) so as to thus define an axial relative positioning of the mounting element (9) with respect to the housing (3).

2. Overpressure valve (1) according to Claim 1, wherein the mounting element (9) has at least two separate cutouts (9a) of said type and the housing (3) has at least two separate corresponding plastic deformations (3b), wherein each of the plastic deformations (3b) projects into one of the separate cutouts (9a), in particular wherein the separate cutouts (9a) and the corresponding separate plastic deformations (3b) are distributed uniformly around the radial outer circumference of the mounting element (9), in particular wherein the separate cutouts (9a) and the corresponding separate plastic deformations (3b) are in each case distributed around the radial outer circumference of the mounting element (9) so as to be opposite one another in pairs.

3. Overpressure valve (1) according to either of the preceding claims, wherein the mounting element (9) has a sleeve portion (9b) which at least partially surrounds the spring element (7) transversely to the longitudinal direction of the spring element (7), in particular wherein the respective cutout (9a) is formed by a respective aperture in the sleeve portion (9b) of the mounting element (9).

4. Overpressure valve (1) according to one of the preceding claims, wherein the mounting element (9) is formed in such a way as to be displaceable in a continuously variable manner in the receiving region (3a) of the housing (3) in the axial direction thereof prior to formation of the at least one plastic deformation (3b) of the housing (3).

5. Overpressure valve (1) according to one of the preceding claims, wherein, apart from the plastic deformation(s) (3b) formed, no further means of fixing is provided between the mounting element (9) and the housing (3).

6. Overpressure valve (1) according to one of Claims 1 to 4, wherein, in addition to the plastic deformation(s) (3b) formed, at least one further means of fixing is provided between the mounting element (9) and the housing (3), in particular wherein at least one further means of fixing is formed by a welding, in particular by laser welding, of the housing (3) to the mounting element (9).

7. Door drive, in particular door closer, having an overpressure valve (1) according to one of the preceding claims.

8. Method for producing an overpressure valve (1) for a door drive, in particular for a door closer, in particular for producing an overpressure valve (1) according to one of Claims 1 to 7, wherein the method comprises at least the following steps: providing a housing (3) having a flow channel (4) formed therein and having a receiving region (3a); introducing a sealing element (5) and a spring element (7) into the receiving region (3a) of the housing (3) in such a way that the sealing element (5) is provided in a manner movable between a closed position, in which it closes off the flow channel (4), and an open position, in which it opens up the flow channel (4), in the housing (3) ; axially inserting a mounting element (9) into the receiving region (3a), and positioning the mounting element (9) in the receiving region (3a) of the housing (3) in such a way that the spring element (7) is clamped between the sealing element (5) and the mounting element (9) in such a way that the spring element (7) preloads the sealing element (5) from its open position into its closed position; wherein the fixing of the mounting element (9) is secured within the housing (3) by the formation of at least one plastic deformation (3b) of the housing (3) at a position in which the spring element (7) preloads the sealing element (5) into its closed position by way of a predefined force, characterized in that, prior to the positioning of the mounting element (9) in the receiving region (3a), at least one cutout (9a) is formed in a radial outer circumference of the mounting element (9), and wherein the at least one plastic deformation (3b) of the housing (3) is formed in such a way as to project into the at least one cutout (9a) so as to thus define an axial relative positioning of the mounting element (9) with respect to the housing (3).

9. Method according to Claim 8, wherein, when assembling the overpressure valve (1), the mounting element (9) is pushed into the receiving region (3a) counter to the force of the spring element (7) by a force corresponding to the predefined preload force and the mounting element (9) is fixed by the formation of the at least one plastic deformation (3a) at the thus obtained relative position with respect to the housing (3).

10. Method according to either of Claims 8 and 9, wherein at least two separate cutouts (9a) of said type are formed in the radial outer circumference of the mounting element (9) and at least two separate plastic deformations (3b) are formed in the housing (3) in such a way that each of the plastic deformations (3b) projects into one of the separate cutouts (9a), in particular wherein the separate cutouts (9a) in the mounting element (9) and the corresponding separate deformations (3b) of the housing (3) are formed distributed uniformly around the radial outer circumference of the mounting element (9), in particular wherein the separate cutouts (9a) in the mounting element (9) and the corresponding separate deformations (3b) of the housing (3) are in each case formed distributed around the radial outer circumference of the mounting element (9) so as to be opposite one another in pairs.

11. Method according to one of Claims 8 to 10, wherein the at least one plastic deformation (3b) of the housing (3) is formed by means of a conical punch.

12. Method according to one of Claims 8 to 11, wherein, apart from the plastic deformation(s) (3b) formed, no further means of fixing is formed between the mounting element (9) and the housing (3).

13. Method according to one of Claims 8 to 11, wherein, in addition to the plastic deformation(s) (3b) formed, at least one further means of fixing is formed between the mounting element (9) and the housing (3).

14. Method according to Claim 13, wherein at least one further means of fixing is formed by a welding, in particular by laser welding, of the housing (3) to the mounting element (9).