Protective collar for an actuating element, in particular a switch

Abstract

The present invention relates to a protective collar for at least partially receiving an actuating element that extends through the housing of a control unit and projects beyond the outer side of the housing. The protective collar has: a base with a through-opening; and a first circumferential collar that is radially spaced from the through-opening and extends from the upper surface of the base in a first direction. The first collar has at least two incisions such that the first collar forms at least two wings, wherein at least one of the wings has at least one predetermined breaking point extending in the circumferential direction.

Description

[0001] The present disclosure relates to protective collars for actuating elements such as switches. The protective collar is particularly suitable for emergency stop switches, also known as emergency stop devices, emergency power-off switches or emergency power-off devices, etc.

[0002] In various different fields, there are various different actuating elements which, if they protrude relative to the surface to which they are attached, need to be protected against unintentional actuation or possibly against damage from lateral loads. A particular class of such actuating elements are emergency stop switches, which are typically easily visible and easily accessible on or near machines and devices and, when actuated, are used to place the machine and the device in a safe state. This can be done in different ways, as is well known in the art. This also contributes in part to the different names, but these names are not always used consistently. Thus, an emergency power-off switch typically effects the disconnection of the power supply from the associated machine or device, while an emergency stop switch is typically able to stop the elements of a moving machine or device without necessarily interrupting the power supply. There are also hybrid forms in which only the energy supply to part of the machine or device is interrupted. In the following description, the term emergency stop switch will be used throughout, regardless of which function is triggered by the particular actuation.

[0003] Emergency stop switches typically take the form of push buttons which can be moved linearly between an on position and an off or stop position. The switches are typically designed such that, after actuation, they do not inadvertently return to the active state. For example, emergency stop switches with an integrated lock are known which can only be moved to the on position after actuation using a key. Alternative emergency stop switches can be moved to the on position, for example, by simply pulling or by a combined rotation and pulling of the push button. Even in the case of those emergency stop switches which do not have an integrated lock, it can be advisable to provide additional fixed locking in the stop position such that only a specific individual, for example an individual with a key, can release the push button.

[0004] The switches may also have a preloading in the stop position such that, after an initial first actuation, the switches automatically perform their full stroke to the stop position. Due to the freely accessible location of the emergency stop switches, the emergency stop switches can be prone to being accidentally actuated or damaged. Incorrect actuation causes an undesired interruption of operation, while damage to the emergency stop switch can impair the function of the switch and thus the safety of the machine or device. Of course, such problems can occur not only with emergency stop switches, but also with other exposed actuating elements.

[0005] Thus, for example, it is known to provide a protective collar for an emergency stop switch, which protective collar at least partially surrounds the impact button as an actuating element and, in particular, prevents lateral loads and, in some cases, also prevents unintentional actuation. Such a protective collar must be designed in such a way that it does not impair the actuation of the emergency stop switch. In particular, the protective collar should be designed in such a way that the emergency stop switch can be actuated with the palm of the hand without any risk of injury to the operator. In addition, depending on the application area, the emergency stop switch and its use are subject to a very wide range of additional requirements, such as, for example, a conventional impact test in which the function of the emergency stop switch is tested with a specific impact force, or also requirements regarding the possible static charge of the switch.

[0006] In the case of repeated impact tests, the protective collar can partially reduce the load on the emergency stop switch, but at the same time the increased load can be transmitted via the protective collar to the switch housing, which can lead to damage to the switch housing. In addition, the protective collar generally also increases the available surface area for the accumulation of static charge, which can lead to problems depending on the application area.

[0007] The present invention aims to provide an improved protective collar for an actuating element such as a switch, in particular an emergency stop switch.

[0008] A protective collar according to claim 1 is provided. Other embodiments of the invention are particularly obtained from the dependent claims.

[0009] In particular, the present invention discloses a protective collar for at least partially receiving an actuating element that extends through the housing of a control device and projects beyond the outer side of the housing, the protective collar comprising the following: a base having a through-opening and a first circumferential collar that is radially spaced from the through-opening and extends from the upper side of the base in a first direction. The first collar has at least two incisions such that the first collar forms at least two wings, wherein at least one of the wings has at least one predetermined breaking point extending in the circumferential direction. Such a protective collar can cause the wings to flex or break in the region of the predetermined breaking point, so that the force acting on the protective collar does not simply pass through the protective collar.

[0010] In one embodiment, the two predetermined breaking points are formed by slots that extend circumferentially over at least 40% of the width of the wing, wherein the slots do not extend as far as the incisions, such that in each case a predetermined breaking point is formed in the region between the end of the slot and the incision. Alternatively, a plurality of predetermined breaking points can also be formed by a series of slots or incisions that are arranged linearly in the circumferential direction of the wing and extend over at least 40% of the width of the wing.

[0011] In one embodiment, a slot or a series of slots or incisions are formed centrally along the circumferential direction of the wing and preferably extend over at least 70% of the width of the wing. Additionally, preferably, at least two wings may have at least one corresponding predefined breaking point for the uniform distribution of forces in the protective collar. To allow additional buckling of the wings, in one embodiment, the first collar extends away from the upper side of the base in an inclined manner such that the space formed between the wings widens away from the base. In this case, the first collar may extend at an angle between 5° and 15° to the plane of the base. In particular, the first collar may have a circular shape.

[0012] To be able to accommodate the fixing element, in one embodiment, through openings are formed in each case in each of two opposite wings and are aligned with the through openings in the opposite wings. In this case, the through openings are preferably arranged between the slot and the free end of the wing. On at least one wing, the protective collar may also have mounting eyelets for the fixing element.

[0013] In another alternative form, the protective collar has a second collar radially arranged inside the first collar, where the second collar surrounds and radially delimits the through opening. The height of the second collar is preferably less than the height of the wings of the first collar and greater than the height of the first collar at the lowest point of the incision.

[0014] On the inner circumference of the through opening, the protective collar may have a step widening towards the lower side, which can be used for example to partially receive and / or fasten a sealing element. In another embodiment, a third circumferential collar is provided, which extends from the lower side of the base and forms a receiving space below the base, which preferably has a diameter greater than that of the through opening. If necessary, such a receiving space formed by the third collar can also receive parts of the actuating element even below the base.

[0015] In an alternative form, the third collar has a structure on its inner circumference adapted to cooperate with a structure on the actuating element or on the housing for the actuating element to prevent the protective collar from rotating relative to the actuating element or the housing.

[0016] In another embodiment, a structure for forming a clamping connection with an element of the actuating element is provided on the inner circumference of the third collar, where preferably a plurality of protrusions evenly spaced in the circumferential direction along the inner circumference of the third collar and extending inwards are provided.

[0017] The invention will be explained in more detail below with reference to the drawings. The drawings show:

[0018] Figure 1 : A schematic perspective plan view of a protective collar for an actuating element such as an emergency stop switch;

[0019] Figure 2 : Cross-section view of the protective collar shown; Figure 1 Schematic cross-sectional view of the protective collar shown;

[0020] Figure 3 : Figure 1 Schematic view of the protective collar shown as seen from below;

[0021] Figure 4 : Figure 1 Schematic perspective view of the protective collar shown as seen from below, in which the emergency stop switch is installed and in the on position;

[0022] Figure 5 : Schematic side view of the protective collar, in which the emergency stop switch is installed and in the off position;

[0023] Figure 6 : Cross-section through Figure 1 Schematic cross-sectional view of the protective collar shown, in which the emergency stop switch is installed and in the off position.

[0024] The position and orientation indications used in the following description refer to the representation in the drawings and should not therefore be considered restrictive. However, they may also relate to the preferred final arrangement.

[0025] The drawings show different views of the protective collar 1 for an actuating element in the form of an emergency stop switch 2 which is only schematically shown in Figures 4 to 6 . Although the protective collar is specifically described below in connection with an actuating element in the form of an emergency stop switch, the protective collar can also be used for other actuating elements having a similar construction but used without an emergency stop function.

[0026] The protective collar 1 is essentially formed by a base 4, a first collar 6, and a second collar 8 and a third collar 10, the second and third collars being optional. The protective collar 1 is formed as an integral unit, and thus the fluid transitions between the foregoing parts. The protective collar is made of, for example, a thermoplastic material or other suitable material, for example in an injection molding process or by another suitable method.

[0027] The annular portion of the protective collar having a horizontal orientation as shown in Figure 2 is considered to be the base 4. Of course, the protective collar 1 can be used in a variety of orientations, and thus the introduction of the horizontal orientation is only for the purpose of describing the arrangement of the different elements relative to each other. The base 4 has a stepped downwardly widening central opening 12, as best shown in Figure 2 . As will be explained in more detail below, the central opening 12 is for passing a portion of the emergency stop switch 2, as is well known in the art. A circumferential groove 14 having a circular bottom is formed in the upper side of the base 4.

[0028] The first collar 6 extends upwardly at the outer edge of the upper side of the base (as Figure 2 shown). As Figure 2 best shown, the first collar 6 extends at an angle to the vertical line such that the space widening away from the base 4 is at least partially surrounded by the first collar 6. The first collar is preferably inclined between 5° and 15° with respect to the vertical line, or in other words, the first collar 6 is inclined between 75° and 85° with respect to the plane defined by the base 4.

[0029] The first collar 6 has a completely circumferential first region that is directly adjacent to the base 4, and a second region where the first collar 6 is interrupted by two cuts 16 and forms two wings 18. A channel (not shown) may be provided in the first region of the first collar 6 and / or in the base 4 so as to be able to (if appropriate) discharge the liquid accumulations occurring in the region of the groove 14 to the outer circumference of the protective collar 1.

[0030] The cuts 16 are in the form of rounded, i.e., rounded in such a way that, in the direction away from the base 4, the wings 18 initially become narrower, but then become wider again, and then become narrower again towards the free end (away from the base 4). The wings 18 seen from above each have a circular shape that substantially follows the circumferential shape of the base 4. Here, the width is considered to be the circumferential length of the wing in the horizontal plane (in the Figure 2 orientation shown) or in a plane parallel to the plane of the base 4.

[0031] Each of the wings 18 has a height measured from the height of the base, which is greater than the stroke of the emergency stop switch 2, as will be explained in more detail below. Formed in each of the wings 18 is a slot 20 that extends substantially parallel to the plane of the base 4 and extends completely from the inner side (the side facing the other wing) to the outer side of the wing. In the region between the end of the slot 20 and the cutout, the slot 20 forms a predetermined breaking point that extends in the circumferential direction and is indicated by a dashed line at 21. The predetermined breaking point 21 is formed because there is less material above and below at the height of the slot along the circumferential direction of the wing 18. Instead of a single slot 20, a series of slots or cutouts may also be provided, whereby a plurality of predetermined breaking points may be formed. In addition to or alternatively to the slot or series of slots or cutouts, at least one groove extending in the circumferential direction of the wing may be provided, which is provided on the inner side and / or the outer side of the wing. In particular, if at least one groove is formed at the height of the slot 20 or at a series of slots or cutouts in the remaining region of the wing 18, a weakened portion of the wing 18 may be formed in the region of the groove thereby to form at least one predetermined breaking point. The slot 20, the series of slots or cutouts and / or the groove preferably extend at least 40% (preferably between 60% and 90%) of the width of the wing 18 at this height and are at a distance from the cutout 16. In particular, the slot 20 or the series of slots or cutouts may be centered between the cutouts 16 in each case. However, alternatively, a slot extending from the cutout 16 to the center of the wing may also be provided in order to form a single predetermined breaking point centered between the slots. The slot 20 or the series of slots or cutouts are formed at a height above the first (fully circumferential) region of the first collar 6. The slot 20 or the series of slots or cutouts are preferably further formed at a height below half the height of the corresponding wing 18. The slot 20 or the series of slots or cutouts are formed in such a way that in each case they allow a certain buckling of the wing 18 in the direction of the base 4, and the corresponding region between the slot 20 and the cutout 16 serves as a predetermined breaking point 21 in order to prevent excessive force from being transmitted to the underlying elements through the protective collar, as will be explained in more detail below. Corresponding predetermined breaking points may also be formed or supported by a series of slots or cutouts or by a groove extending in the circumferential direction.

[0032] In addition, above the corresponding slots 20, circular through-openings 22 are formed in each wing portion, the size of the circular through-openings being set such that a latching element (not shown) can pass therethrough, as will be described in more detail below. The through-openings 22 of the wing portions 18 are each centered between the incisions 16 and are aligned with each other such that the latching element can be guided in a straight line through the two through-openings 22. The through-openings 22 are formed at a height above half the height of the respective wing portion 18, where it is assumed here that the height of the through-opening 22 is defined by its center point in each case. Below the through-opening 22, in the case where the first collar 6 deviates from the other inclination, the outer side of the first collar 6 is formed by a wall section 24 extending substantially vertically (perpendicular to the plane of the base). However, the inner side of the first collar 6 extends here as in the normal case, such that in this region, the wall thickness of the first collar 6 tapers away from the base 4 in the direction of the through-opening 22.

[0033] An annular receiving element 26 is provided on one of the wing portions 18. The receiving element 26 is formed adjacent to the upper edge on the outer side of the wing portion 18 and has a horizontal orientation. Accordingly, the opening 27 in the receiving element 26 extends in the vertical direction. The receiving element 26 is arranged offset with respect to the through-opening 22, i.e., not centered between the incisions. The size of the opening 27 in the receiving element 26 is set such that a latching element (not shown), such as a fixing bolt, a hook of a hook-and-loop lock, etc., can pass through.

[0034] The second collar 8 is located radially inside the first collar and likewise extends upward from the upper side of the base ( Figure 2 ). As Figure 2 best shown, the second collar 8 forms an extension of the central opening 12 extending through the base 4. Accordingly, the second collar 12 is formed directly at the innermost edge of the base 4 and even projects radially inwardly above the inner edge, such that a step is formed at the transition between the base 4 and the second collar 8. Due to this step, the central opening 12 has an upper region with a smaller diameter (formed by the second collar 8) and a lower region with a larger diameter (formed by the base 4).

[0035] The second collar 8 has an upper surface vertically located between the lowest point of the incision 16 and the slot 20 in the wing portion 18.

[0036] The third collar 10 extends downward at the outer edge of the lower side of the base ( Figure 2 ). As Figure 2 best shown, the outer wall of the third collar 10 extends at an angle to the vertical line such that the inner circumference of the third collar tapers away from the base 4. However, the inner wall of the third collar 10 extends perpendicular to the lower side of the base, such that the inner wall of the third collar defines a cylindrical receiving space 30 below the base. The transition between the inner wall of the third collar 10 and the base 4 is rounded, as visible in Figure 2 .

[0037] A plurality of inwardly protruding protrusions 32 (here four) are provided on the inner wall at the lower end of the third collar 10. The protrusions 32 are circumferentially equally spaced apart and each has an equal dimension in the circumferential direction. The protrusions serve as latching hooks for fastening the protective collar 1 to the emergency stop switch 2 and also prevent torsion between the protective collar and the emergency stop switch.

[0038] The lower side of the third collar 10 is not flat but has a surface adjacent to the inner wall that is retracted relative to the surface directly adjacent to the outer wall. The transition between the two surfaces is formed by an inclined plane, and the annular space thus formed is adapted to receive an annular seal 34 (as Figure 6 shown), as will be recognized by those skilled in the art. By shaping the lower side of the third collar 10, the corresponding seal can be centered relative to the protective collar 1. By making the outer wall more downward than the inner wall, lateral displacement of the seal 34 in the assembled state can be restricted or prevented.

[0039] An exemplary construction of the actuating element in the form of an emergency stop switch 2 to which the protective collar 1 is applicable will now be described in more detail below. In this case, the emergency stop function of the actuating element is not important since the protective collar can also be advantageously used in combination with other actuating elements. The emergency stop switch 2 can be best shown in a Figure 6 sectional view, in which the housing 40 of the control unit (not shown) is also indicated, to which the emergency stop switch 2 with the protective collar 1 is attached. In this case, the housing has a through-opening through which a part of the emergency stop switch 2 extends, as is well known in the art.

[0040] The emergency stop switch 2 basically consists of a fastening unit 44, a guiding and latching unit 46, and an actuating element 48.

[0041] The fastening unit 48 consists of a substantially hollow cylindrical body 50 having different inner and outer diameters. Thus, the outer wall of the body 50 has an outer diameter in its upper region 52 that matches the inner diameter (in the region of the third collar) of the cylindrical receiving space 30 of the protective collar 1 so as to be closely received therein. The upper region 52 of the body 50 is thus structured such that it can be latched with the protrusions 32 of the third collar 10 of the protective collar 1 to fasten the two to each other.

[0042] Adjacent to the upper region 52 is the central region 54 of the body, whose outer diameter is smaller than that of the upper region 52. Thus, a step is formed between the upper region 52 and the central region 54. Threads are provided at least partially on the outer circumference of the central region.

[0043] The central region 54 also abuts the lower region 56, which in turn has an outer diameter smaller than that of the central region 54. At the lower end of the lower region 56, a plurality of protrusions 58 are provided, which are equally spaced apart along the circumferential direction of the lower region.

[0044] Although the outer diameter of the upper region 52 is larger than the through-opening in the housing 40, the outer diameter of the central region 54 is smaller than the through-opening in the housing 40. Thus, the body 50 can be guided from above through the through-opening in a manner such that it rests on the housing 40, with a step formed between the upper region 52 and the central region 54. A nut 60 screwed onto the threads of the central region from inside the housing 40 allows the body 50 to be firmly fastened to the housing, as Figure 6 indicated. Since the body is latched to the protective collar 1, the protective collar can also be firmly fastened to the housing via the body. The central region 54 of the body 50 also has an outwardly protruding nose that mates with a corresponding groove in the through-opening in the housing 40, such that the body can only be guided through the through-opening in the housing 40 in a specific rotational position and is thus also accommodated therein in a rotationally fixed manner.

[0045] The inner wall of the body 50 has a step in the upper region 52 such that the inner circumference of the upper region widens upwards. The inner wall of the body 50 has another step at the transition between the central region 54 and the lower region 56 such that the inner circumference widens upwards. At the lower end of the body 50, a circumferentially inwardly extending flange 62 is also provided, which keeps the central opening unobstructed.

[0046] The guiding and latching unit 46 is at least partially received in the body 50 of the fastening unit 48 and has a rather complex structure, and only its most important elements will be explained in more detail here. First, the guiding and latching unit 46 forms a central vertically extending hollow cylindrical guiding section 66, which forms a guiding surface on the inside. A plurality of openings (e.g., four) are formed in this guiding surface at a certain height, and each of the openings houses a spherical element 68. The spherical elements 68 are each received in the openings in such a way that they can move perpendicular to the guiding surface, i.e., between a first position and a second position, in which the spherical element projects inwards beyond the guiding surface in the first position and does not project beyond the guiding surface in the second position. The spherical elements 68 can each be preloaded to the first position via preloading elements (not shown). The hollow cylindrical guiding section 66 has a plurality of axially extending slots (e.g., four) that are equally spaced circumferentially in the upper section.

[0047] The guiding and latching unit 46 also includes an annular counter-bearing element 69 provided at the upper end of the central vertically extending hollow cylindrical guiding section 66 and can be formed, for example, as an inwardly extending flange.

[0048] The guiding and latching unit 46 forms an outer cylindrical region 70 which is closely received in the central region 54 of the body 50 of the fastening unit 48 (and partly received in the upper region 52) and extends upwardly beyond the upper region 52 of the body 50. The uppermost section of the outer cylindrical region 70 extends into the central opening 12 of the protective collar 1. In the region of the step in the inner wall of the upper region 52 of the body 50, the outer cylindrical region 70 has a radially outwardly extending flange 72 which rests on the step.

[0049] The actuating element 48 consists essentially of a head unit 80, a shaft section 82 and a transmission element 84.

[0050] The head unit 80 consists of a body 86 and a cover 88. The body 86 has an upper plate element 90 which has a central recess on its upper side, the dimensions of which are set to receive the cover 88. Provided on the lower side of the plate element are an outer peripheral flange 92, an inner peripheral flange 94 and a plurality of guiding elements 96, each of which extends substantially vertically downward.

[0051] The flange 92 is radially inwardly offset relative to the circumference of the plate element 90 and has a rounded outer circumference which tapers away from the plate element. The inner circumference forms a vertically extending cylindrical surface.

[0052] The inner flange 94 forms a vertically extending hollow cylinder having a cylindrical receiving space which is open at the bottom and bounded at the top by the plate element 90. In the region of the recess in the plate element 90, a vertically extending through-opening is provided which leads into the receiving space of the inner flange 94 and is adapted for fastening elements such as screws to pass through.

[0053] A plurality of guiding elements 96 are provided on the lower side of the plate element 90, between the outer flange 92 and the inner flange 94. The number of guiding elements 96 corresponds to the number of slots in the upper region of the hollow cylindrical guiding section 66, and the guiding elements 96 are aligned with the corresponding slots. The lower edge of the guiding element 96 can limit the downward movement of the head unit 80, as Figure 6 shown.

[0054] The shaft section 82 of the actuating element is formed by a solid cylindrical shaft section 82 having a shaped outer circumferential surface. The upper region 100 of the shaft section 82 has a first outer circumference which is adapted to receive, in particular closely receive, in the receiving space of the inner flange 94. The upper region 100 is also provided with an axially extending opening, in particular a threaded opening for receiving a fastening element, via which the shaft section 82 can be fastened to the plate element 90 of the head unit, as Figure 6 indicated.

[0055] Adjacent to the upper region 100 is the upper central region 102 of the shaft section, which has an enlarged outer circumference so as to form between the upper region 100 and the upper central region 102. This can be adjacent to the lower side of the inner flange 94, as Figure 6 shown. The outer circumference of the upper central region 102 is smaller than the inner circumference of the hollow cylindrical guide section 66 of the guide and latch unit 46.

[0056] The central region 104 of the shaft section 82 then adjoins the upper central region, where the outer circumference is enlarged relative to the upper central region 102. Thus, a step is again formed at the transition between the upper central region 102 and the central region 104. The outer circumference of the central region 104 matches the inner circumference of the hollow cylindrical guide section 66 so as to be closely received therein and guided. Specifically, an axial guide for the shaft section 82 is thus formed. In the outer circumference, a circumferential groove is formed at a predetermined height and dimensioned such that it can receive the spherical element 68, as Figure 6 shown. In this position, the shaft section 82 is locked in place by the spherical element 68. The groove is shaped such that the spherical element 68 is pushed out of the groove and into an opening in the hollow cylindrical guide section 66. Thus, the latch can be overcome by a corresponding tension, however, this tension is significantly higher than when no corresponding latch is provided.

[0057] The lower central region 106 with a reduced outer circumference relative to the central region 104 adjoins the central region 104 of the shaft section 82. Thus, a reverse step is now formed at the transition between the central region 104 and the lower central region 106. The outer circumference of the lower central region 106 basically corresponds to the outer circumference formed by the bottom of the groove in the central region 104.

[0058] When the actuating element 48 is not in the stop position, as Figure 6 shown, the head unit 80 moves upward together with the shaft section 82 until the spherical element 68 abuts against the reduced outer circumference in the region of the lower central region 106, thus again effecting a certain latching action. In this case, the spherical element 68 counteracts the free downward movement of the shaft section 82. However, the corresponding movement is released when a certain pressing force is exceeded.

[0059] The lower region 108 of the shaft section 82 also adjoins the lower central region, which in turn has a further reduced outer circumference such that a downward-facing step is formed at the transition. The lower region 108 is dimensioned to be received in the cylindrical receiving space in the transmission element 84.

[0060] The transmission element 84 basically has an inverted top hat shape, having a middle cylindrical section 110 forming the cylindrical receiving space and having a circumferential flange section 112.

[0061] In addition, as Figure 6 can be seen, the actuating element 48 has a preloading spring 120 in the form of a compression spring. The preloading spring 120 extends between the counter-bearing element 69 and the upward-facing step at the transition between the upper central region 102 and the central region 104. The preloading spring 120 preloads the actuating element 48 downward relative to the guiding and latching unit 46, i.e., in the Figure 6 shown stop position. In this position, for example, the transmission element 84 will act on a control unit (not shown) to achieve a desired function, such as an emergency stop.

[0062] As can be seen, the actuating element 48 can be pulled upward against the preloading of the preloading spring 120 until the spherical element 68 abuts against the reduced outer circumference in the region of the lower central region 106, and thereby a certain latching action is developed. Here, the transmission element 84 moves together with the shaft section 82 in such a way that it acts on the control unit, so that a desired function, such as starting the device or another function, can then be executed. The latching action exerted by the spherical element is greater than the force exerted by the preloading spring 120, so that the actuator will remain in this position (also referred to as the on position). However, even a small downward movement of the actuating element 48 is sufficient to overcome the latching action. Once the latching action is eliminated, the actuating element 48 will be moved by the preloading spring 120 to the Figure 6 shown position.

[0063] In addition, a bellows-type seal 130 is also visible in Figure 6 . The lower end of the bellows-type seal 130 is received and clamped between the upper surface of the flange 72 of the outer cylindrical region 70 and the lower side of the base 4 of the protective collar 1. The vertically extending portion 134 of the bellows-type seal 130 is guided by the section of the outer cylindrical region 70 located above the flange 72 and partially passes through the central opening 12 in the protective collar 1. Attached to the portion 134 is a bellows portion 136, the upper end of which can be clamped between the plate element 90 of the head unit 80 and the cover 88 (in the region of the groove in the plate element 90). Obviously, the bellows-type seal 130 can prevent water from entering the inner region of the actuating element in the form of the emergency stop switch 2.

[0064] When the combination of the protective collar 1 and the actuating element 2 is mounted on the housing 40 of the switch unit in the Figure 6 shown manner, the protective collar 1 surrounds the actuating element 2. In this case, the actuating element is at least partially protected, in particular from lateral influences and unintentional actuation, while substantially not impeding the actuation of the actuating element.

[0065] By means of the cutout 16, the actuating element 2, although surrounded by the protective collar, can be gripped by the head section and pulled upward out of, for exampleFigure 6 the position shown (stop position) and into an "on" position (not shown), in which the actuating element 2 is held by the latching action of the spherical element 68. From the "on" position, the actuating element 2 can be easily actuated, for example, by pressing with the heel of the palm, since only a small initial movement is required to overcome the latching action. Then, with the assistance of the preloading spring 120, the actuating element 2 automatically moves to the stop position (or also the off position) as shown in Figure 6 the stop position shown (or also the off position). The impact force applied to the actuating element 48 and usually then also applied to the protective collar 1 is absorbed by the slot 20 in the wing 18 of the protective collar. Thus, the force acting on the housing 40 can be reduced. In addition, the area of the wing 18 in the extension of the slot 20 can be designed as a predetermined breaking point 21, such that in the case of a force exceeding the predetermined force, the protective collar 1 will break here in order to prevent the force from being transmitted to the housing 40 and thus potentially damaging the housing. The widened shape of the protective collar 1 formed by the inclined extension of the wing 18 can also promote the spring deflection of the wing 18, which, in particular, also in combination with the groove in the base, such that, for example, the impact force is absorbed in the protective collar 1 and not completely transmitted to the housing 40.

[0066] For example, when the actuating element 2 is in the stop position (or also in the off position) as shown in Figure 6 the stop position shown, the hook of a latching element such as a latching bolt or a snap lock (not shown) can pass through the through-opening 22 and be locked to prevent unauthorized removal. Such a latching element will then prevent the actuating element 48 from moving to the on position. If a latching element is not required, it can be received, for example, in the receiving element 26 adjacent to the upper edge of the wing 18. Thus, the corresponding latching element can be easily held ready.

[0067] Therefore, the protective collar 1 provides a variety of functions beyond those of a normal protective collar. Although the protective collar has been described in connection with a specific embodiment of the actuating element 2, the protective collar can also be used with differently configured actuating elements, as will be appreciated by those skilled in the art, which is particularly suitable for use in combination with actuating elements having linear actuation. The function of the actuating element is obviously not of decisive importance either, and different actuation positions can also precisely cause reverse operations relative to those shown. For example, Figure 6The position shown may be, for example, the on position. However, the shape of the protective collar may also be different from the shape shown, or certain elements may be omitted. If the latching of the actuating element 48 is not required, the through-opening 22 and the receiving element 26 may be omitted, for example. In some embodiments, for example, if the actuating element does not have a protruding fastening unit (such as the fastening unit 44), the third collar 10 may be omitted. In this case, for example, the lower side of the base 4 may abut flatly against the housing. In accordance with the foregoing description, various possible variations will become apparent to those skilled in the art, and the description is not intended to limit the scope of the invention, which is defined by the appended claims.

Claims

1. A protective collar for at least partially receiving an actuating element, the actuating element extending through a housing of a control unit and protruding beyond an outer side of the housing, the protective collar comprising: a base having a central opening for passage therethrough of a portion of the actuating element; and a first circumferential collar spaced radially relative to the central opening and extending from an upper side of the base in a first direction, wherein the first circumferential collar has at least two incisions such that the first circumferential collar forms at least two wings, and wherein at least one of the wings has at least one predetermined breaking point extending in a circumferential direction.

2. The protective collar according to claim 1, wherein at least two predefined breaking points are formed at an end of the slot, the at least two predefined breaking points extending over at least 40% of a width of the at least one wing, wherein the slot does not extend as far as the incision, the predefined breaking points being formed between the end of the slot and the incision.

3. The protective collar according to claim 1, wherein a plurality of predefined breaking points are formed by a series of slots or incisions, the series of slots or incisions being arranged linearly in a circumferential direction of the at least one wing and extending over at least 40% of a width of the at least one wing.

4. The protective collar according to claim 2, wherein the slot is formed centrally in the circumferential direction of the at least one wing.

5. The protective collar according to claim 2, wherein the slot extends over at least 70% of a width of the at least one wing.

6. The protective collar according to claim 1, wherein the at least one predefined breaking point is at least partially formed by a groove, the groove extending in a circumferential direction of the at least one wing and being located on an inner circumference and / or an outer circumference of the at least one wing.

7. The protective collar according to claim 1, wherein the at least two wings have at least one corresponding predefined breaking point.

8. The protective collar according to claim 1, wherein the first circumferential collar extends from an upper side of the base in an outwardly inclined manner such that a space formed between the wings widens away from the base.

9. The protective collar according to claim 8, wherein the first circumferential collar extends at an angle to a plane of the base, the angle being between 5° and 15°.

10. The protective collar according to claim 1, wherein the first circumferential collar has a circular shape.

11. The protective collar according to claim 1, wherein through openings are formed in each of the at least two wings and the through openings in one wing are aligned with the through openings in the other wing.

12. The protective collar according to claim 11, wherein the through-opening in one of the wings is arranged between the at least one predetermined breaking point and the free end of the wing in the vertical direction of the wing.

13. The protective collar according to claim 1, wherein at least one of the wings has a mounting eyelet for a fixing element.

14. The protective collar according to claim 1, wherein the protective collar has a second circumferential collar radially arranged inside the first circumferential collar, and the second circumferential collar surrounds and radially delimits the central opening.

15. The protective collar according to claim 14, wherein the height of the second circumferential collar is less than the height of the at least two wings of the first circumferential collar and greater than the height of the first circumferential collar at the lowest point of the incision.

16. The protective collar according to claim 14, wherein a step widened towards the lower side of the base is formed on the inner circumference of the central opening.

17. The protective collar according to claim 14, further comprising a third circumferential collar, the third circumferential collar extending from the lower side of the base and forming a receiving space below the base, the receiving space having a diameter greater than the diameter of the central opening.

18. The protective collar according to claim 17, wherein the third circumferential collar has a structure on the inner circumference of the third circumferential collar, and the structure is adapted to cooperate with a structure on the actuating element or a housing for the actuating element to prevent the protective collar from rotating relative to the actuating element or the housing.

19. The protective collar according to claim 18, wherein the structure on the inner circumference of the third circumferential collar forms a clamping connection with an element of the actuating element, and a plurality of protrusions evenly spaced in the circumferential direction along the inner circumference of the third circumferential collar extend inward from the third circumferential collar.

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