Device for machining coil springs

Abstract

Device for machining coil springs, comprising: - a machine body (2) with a table top (3), - a loading device (10) arranged on the table top (3) and rotatable about a first vertical axis (11) with at least one rotatable loading plate (12, 13) with a plurality of spring receptacles (18) which are arranged eccentrically to the first vertical axis (11) and are each designed to receive a coil spring; - a grinding unit (20) forming a grinding chamber (21) into which the at least one loading plate (12, 13) can be transferred from a loading position to a machining position; - a discharge unit (40) arranged on the table top (3) outside the grinding chamber (21) for discharging the coil springs after their machining; and - a unit (30) for controlling the device during the machining of the coil springs; characterized by - that the discharge unit (40) has a shutdown module (41) that is operatively connected to the control unit (30).

Description

[0001] The invention relates to a device for machining coil springs according to the preamble of claim 1.

[0002] In industrial production, especially in spring manufacturing, fixtures are used for machining workpieces such as coil springs. The end surfaces of these primarily metallic coil springs must be produced to specified accuracy requirements. When producing coil springs in large quantities, optimal fixture utilization, short machining times, and operator safety are particularly important. A fixture for machining coil springs is typically a spring end grinding fixture.

[0003] Helical springs are machine elements that are needed in large quantities and various forms in many applications, for example as load-bearing springs or valve springs. A helical spring is a compression spring made of wire that is twisted or wound and has gaps between the coils.

[0004] The spring ends, that is, the two axial end faces of helical springs, are of particular importance for their reliable function during intended use. The spring ends, or rather the end faces of the spring ends, have the function of transmitting the spring force acting on a connecting body. They are typically designed so that compression occurs as axially as possible in every position of the spring. Spring end grinding, i.e., the machining of the spring ends by grinding, is intended to create perpendicular bearing surfaces for the connecting bodies. The spring ends must be ground parallel to each other.

[0005] End grinding of springs is a crucial step in the manufacturing process of helical springs made from cold-formed wire. The goal is to optimize this process to produce helical springs with high productivity, without compromising the quality or safety of the finished products.

[0006] It is known to design spring end grinding devices in such a way that several steps of a manufacturing process can be performed simultaneously in order to achieve the highest possible utilization. For example, spring end grinding devices are known that include a loading device with two movable loading plates for holding workpieces. One of these loading plates is in a grinding position during the grinding process, while the other is in a loading position for loading or unloading. This allows the loading plates to be moved to the other position without any loss of time after the grinding process is completed, in order to perform the next manufacturing step. Occupational safety is of paramount importance with such a spring end grinding device.It must be ensured that the grinding area around the grinding zone is secured by rotating grinding wheels during grinding, while the loading area remains accessible to load or unload the loading plates with workpieces.

[0007] Spring end grinding devices are also known whose loading mechanism comprises only a single loading plate. This loading plate can be loaded with coil springs while it continuously rotates, allowing the coil springs to be moved into a grinding position. The coil springs are machined in the grinding zone. After one pass through the grinding zone, the coil springs are removed. Occupational safety is also important with this type of spring end grinding device, as not only the grinding area around the grinding zone must be secured, but safety precautions must also be taken during the loading and unloading of coil springs on the loading plate.

[0008] Spring end grinding often employs the so-called double-sided surface grinding method, in which the coil springs are held unloaded in spring holders of a loading plate. A numerically controlled spring end grinding device suitable for the double-sided surface grinding method comprises a grinding unit, a loading device, and a control unit for regulating the loading device and grinding unit.

[0009] The grinding unit comprises two rotatable grinding wheels with axes of rotation, which are usually aligned coaxially or slightly inclined towards each other. A grinding chamber is formed between the opposing side surfaces of the grinding wheels.

[0010] A loading device, which can be rotated more or less parallel to the axis of the grinding wheels, comprises at least one loading plate. This plate has numerous off-axis spring mounts, each of which can hold a coil spring. The spring axes of the coil springs mounted in the spring mounts should run as parallel as possible to the axis of rotation of the loading device and thus be perpendicular to the abrasive surfaces of the grinding wheels. To accommodate a maximum number of springs per load, the spring mounts are often arranged in a ring at various radial distances from the axis of rotation.

[0011] During the grinding operation, there is a distance between a vertical axis of the grinding unit and a vertical axis of the loading device. In this operation, the coil springs, which are placed in the spring holders of the loading plate, are gradually moved through the grinding chamber between the rotating grinding wheels by rotating the loading plate. During this operation, both ends of the coil springs located in the grinding chamber are simultaneously ground. At least one section of the loading plate can be moved from a loading position outside the grinding chamber, where the spring holders of the loading plate can be fitted with coil springs, to a grinding position within the grinding chamber.

[0012] A basic distinction is made between two grinding methods for spring end grinding devices.

[0013] In continuous grinding, the grinding wheels are fixed and the final dimension for the helical springs being machined can be ground in a single pass. The loading table rotates at a constant, slow speed or continuously at a pulsed rate. Loading and grinding occur simultaneously. Typically, one grinding wheel is angled. This application is more commonly used with smaller wire diameters.

[0014] In contrast, an electronic control system allows for the adjustment of a constant or pulsed infeed movement of a grinding wheel, proportional to the grinding force, to grind the coil springs to a final dimension. The at least one loading plate rotates at a constant speed, which is as high as possible depending on the specific coil spring. The loading and grinding cycles can be performed sequentially. Both grinding wheels are parallel. This grinding method is primarily used for coil springs with large wire diameters. This grinding method is preferably implemented with two loading plates, which are mounted opposite each other on a loading device. The loading device can move the loading plates between a loading and a grinding position by rotating them.

[0015] After the coil springs have been machined by the grinding wheels, they can be transferred to an unloading position by means of at least one loading plate. In this position, the coil springs, held in individual spring holders on the loading plate, are discharged into a discharge unit. In the simplest case, the discharge unit consists of an outlet opening on a loading device supported by a tabletop. The coil springs fall downwards through their spring holders by gravity and can be collected in a container. For larger quantities of coil springs, it is conceivable that a conveying device, in particular a conveyor belt, is provided below the machine base of a spring end grinding device for the continuous removal of machined coil springs. The machined coil springs can then, for example, undergo heat treatment.

[0016] Patent EP 2 926 948 B1 discloses a spring end grinding device comprising a rotary table, at least one eccentrically mounted loading plate, and a grinding unit with two grinding wheels. The essential feature is the structure consisting of an inner grinding chamber, which encloses the grinding zone, and an outer grinding chamber that partially encloses it. To increase occupational safety and limit the spread of grinding dust and sparks, the inner grinding chamber has at least one door which, when closed, separates the outer chamber from the grinding zone. This inner grinding chamber door is additionally equipped with a first cooling device, the outlet opening of which is directed towards the grinding zone.

[0017] Patent DE 10 2020 205 721 B4 discloses a loading plate for a spring end grinding device, which can be fixed to the loading plate shaft without play by means of a clamping device attached to the base body. This clamping device is designed as a flange with a sleeve section and a clamping section divided circumferentially. The backlash-free fastening prevents reversal and ensures high rigidity, which in particular enables trouble-free automatic loading of the spring holders.

[0018] When unloading coil springs from the spring holders of a loading tray into the unloading unit, it sometimes happens that coil springs become jammed in the spring holders, get stuck, and do not fall into the unloading unit. This is particularly problematic because the loading tray continues to rotate. A jammed coil spring would be sheared off between the loading device and the stationary tabletop as the loading tray continues to rotate, potentially causing a malfunction. To counteract this malfunction and a possible machine stoppage, machine operators sometimes manually push jammed coil springs out of the spring holders so that the coil springs fall into the unloading unit. This procedure is dangerous and can lead to injuries to the machine operator. Furthermore, it is impossible to predict exactly where a coil spring will become jammed.One possibility would be a robotic manipulator equipped with an ejector plunger, which would safely and automatically eject the machined coil springs from the spring holders on the loading plate. However, such an unloading device would not be practical due to the additional design and financial costs, as well as the uncertainty of a coil spring jamming.

[0019] The invention is based on the objective of further developing a device for machining coil springs, in particular a spring end grinding device, in such a way as to improve the safety for a machine operator.

[0020] This problem is solved by the fact that the discharge module of the device further developed by the inventor has a shutdown module that is operatively connected to the control unit.

[0021] This shutdown module, which is operatively connected to the unloading unit, ensures the safe shutdown of the spring end grinding device, particularly the loading device, in the event of a malfunction. A malfunction could involve a coil spring jamming during unloading. However, it could also be caused by an unwanted external intervention, such as the machine operator inserting their hands into the spring receptacles of the loading plate.

[0022] The spring end grinding device according to claim 1 provides a cost-effective and efficient way to protect a machine operator from dangerous interference with the machine and from injury. Furthermore, it minimizes the effort required for recommissioning after a malfunction or production downtime caused by a machine stoppage.

[0023] Advantageously, the unloading unit is arranged below the loading plate so that, after machining, the coil springs fall from the spring receptacles of the loading plate into the unloading unit under the influence of gravity. The spring receptacles are cylindrical receptacles for the coil springs, with the opposing end faces of the spring receptacles being open.

[0024] In a preferred embodiment, the loading device comprises only one loading plate rotatable about a vertical axis, with this loading plate being centrally located on a non-rotating tabletop. In the loading position, the loading plate can be fitted with coil springs while the loading plate continues to rotate continuously, allowing the coil springs within it to be moved into a grinding position. This embodiment is characterized by a simpler design and lower costs.

[0025] Advantageously, the shut-off module can be inserted into an outlet opening of the discharge unit that is molded into the tabletop. The shut-off module can conveniently have a mounting tab, allowing it to be attached to the outlet opening of the discharge unit by means of a detachable or permanent connection. A detachable connection could, for example, be a screw connection, in which case the mounting tab would have through-holes for receiving screws. Alternatively, the shut-off module can be permanently connected to the discharge unit via a weld or adhesive bond using the mounting tab.

[0026] In the simplest case, the unloading unit is designed as an integral part of the table top and has an outlet opening on the table top of the machine base, through which the coil springs can be received and removed. After the coil springs in the spring holders have been machined by the grinding unit, the loading plate rotates to a position where the unloading unit is located. Due to the action of gravity, the machined coil springs fall downwards through a lower opening in the spring holder into the outlet opening of the unloading unit.

[0027] The outlet opening of the discharge unit can be circular, rectangular or trapezoidal and is designed to receive at least one coil spring from the spring receptacle of a loading plate, preferably several coil springs from the spring receptacles of a loading plate.

[0028] Advantageously, the unloading unit is designed as a separate module and can be mounted below the at least one loading plate. This separate module comprises a container open at two opposing end faces for accommodating the shut-off module. The unloading unit, designed as a separate module, can be an open container with a circular, rectangular, or trapezoidal cross-section and is suitable for holding coil springs. The container can be a welded, bent, or other joined manufactured part. The separate module can be mounted at a suitable location below the at least one loading plate, for example, on the machine base. A corresponding recess can be provided on the machine base for this purpose, to which the separate module can be attached. Advantageously, this also allows existing spring end grinding devices to be equipped with an unloading unit and a shut-off module.The unloading unit, designed as a separate module, can be connected to a collection container for coil springs and / or a conveyor system for transporting coil springs, just like the unloading unit designed as an integral part of the tabletop.

[0029] The shutdown module is preferably designed as a tactile flap with an integrated sensor. The tactile flap is understood as a mechanical actuating element and can have the form of a sheet metal part, which is hinged to a base body of the shutdown module via an actuation point. Preferably, the actuation point is a pivot point around which the tactile flap is adjustable, in particular pivotable. If a coil spring were to jam, it would contact the tactile flap and trigger an adjustment, in particular a pivoting of the tactile flap, via the actuation point. An adjustment of the flap, in turn, triggers a signal at the sensor. In this case, a signal from the sensor is transmitted to the control unit of the spring end grinding device and causes the charging device to stop.

[0030] The sensor can be designed as a pressure safety sensor or as an inductive safety sensor. In either case, the sensor meets the requirements for the safe shutdown of the spring-end grinding device, in particular the charging device. A safety sensor fulfills the functional safety approval requirements of the Machinery Directive (e.g., PL d).

[0031] Furthermore, the safety of the spring end grinding device can be further improved by making it possible to load the charging device only when the shutdown module is installed.

[0032] The grinding unit expediently features a pair of grinding wheels with two rotatably mounted and separately driveable grinding wheels, a first of which is arranged above and a second grinding wheel below the loading device.

[0033] In a further advantageous embodiment, the loading device comprises a first loading plate rotatable about a second vertical axis and a second loading plate rotatable about a third vertical axis. Each of these two loading plates is provided with a plurality of spring receptacles, arranged eccentrically to the second and third vertical axes and each designed to accommodate a coil spring. In this embodiment, the two loading plates are advantageously arranged opposite each other on the now rotatably designed tabletop. An advantage of this embodiment is that a large number of coil springs can be processed using two loading plates. One loading plate, which is in a loading position, can be fitted with coil springs, while the coil springs in the second loading plate can be machined in the grinding chamber of the grinding unit.

[0034] Preferred embodiments of the invention are explained below with reference to figures. Fig. Figure 1 shows a schematic side view of a spring end grinding device according to an embodiment of the invention; Fig. 2 shows a schematic side view of a spring end grinding device according to a further embodiment of the invention; Fig. Figure 3 shows a top view of the tabletop of the spring end grinding device. Fig. 2; Fig. Figure 4 shows an oblique perspective view of the tabletop. Fig. 3 Fig. Figure 5 shows a perspective view of a spring end grinding device according to the embodiment shown. Fig. 1; Fig. Figure 6 shows a perspective detail view of the tabletop with shutdown module according to the embodiment of Fig. 1 or Fig. 2 Fig. Figure 7 shows a side view of the shutdown module.

[0035] In all embodiments, the same reference numerals refer to identical or equivalently functioning parts. In the embodiment of Fig. The device in question is for machining coil springs, specifically a spring end grinding device 1, which operates according to the principle of double-sided surface grinding in a continuous process (throughfeed grinding). The essential components of the spring end grinding device 1 are a loading device 10 and a grinding unit 20, which are supported by a machine base 2. The machine base 2 can consist of several different supporting elements, which may be bolted, welded, or joined in any other way. The function of the machine base 2 is to support the components of the spring end grinding device 1 and to absorb the forces generated during the machining of coil springs.

[0036] The loading device 10, rotatably mounted on the machine base 2 about a vertical axis 11, comprises a loading plate 12 rotatable about a vertical axis 11. The grinding unit 20 is rotatably mounted on the machine base 2 about a grinding wheel axis 24, 25. The loading device 10 and the grinding unit 20 are spaced apart from each other on the machine base 2, with the axis 11 and the grinding wheel axis 24, 25 of the grinding unit 20 being parallel to each other. The loading device 10 is positioned vertically upwards at a distance from a table plate 3 mounted on the machine base 2, the table plate 3 being fixedly connected to the machine base 2. Furthermore, the loading device 10 has a loading plate shaft 16 rotatable about the axis 11, which is driven by a drive motor (not shown). The loading plate 12, mounted on the loading plate shaft 16, can be driven by a control unit 30.The rotational speed is adjustable depending on the application. The loading plate 12 has spring mounts 18 for the unloaded mounting of coil springs. The spring mounts 18 are made of [material not specified]. Fig. 4 is visible.

[0037] The coil springs located in the loading plate 12 can be transferred from a loading position to a machining position, in which the coil springs are continuously machined by a grinding unit 20. The grinding chamber 21 is shielded on the inside, i.e., on the side of the spring end grinding device 1 facing the grinding chamber 21, by a grinding chamber cover 50 arranged on the machine base 2. This provides at least partial protection for the machine operator from sparks generated during machining and from grinding dust. At least part of the grinding chamber cover is height-adjustable.

[0038] The grinding unit 20 comprises a first grinding wheel 22, which is rotatably mounted about a first grinding wheel axis 24, and a second grinding wheel 23, which is rotatably mounted about a second grinding wheel axis 25. In the embodiment of Fig. 1. The grinding wheels 22, 23 are aligned parallel to each other and coaxially, so that they have a corresponding grinding wheel axis 24, 25. In an embodiment not shown, the grinding wheel axes 24, 25 can be adjusted to an angular position deviating from the vertical, so that the two grinding wheels are inclined to each other.

[0039] The first grinding wheel 22 can be driven via a first grinding wheel shaft 26 by means of a first grinding wheel shaft drive 28. The second grinding wheel 23 can be driven via a second grinding wheel shaft 27 by means of a second grinding wheel shaft drive 29. From the side view in Fig. Figure 1 shows that the first grinding wheel 22 is located directly below the loading device 10. The coil springs to be machined rest within the grinding chamber 21, essentially on a surface of the first grinding wheel 22. The second grinding wheel 23 is located opposite the first grinding wheel 22 and above the loading device 10. For through-feed grinding, the grinding wheels 22 and 23 are only adjusted for machine setup purposes. During through-feed grinding, the grinding wheels are not adjustable, and the final dimension for the coil springs to be machined can be ground in a single pass. As a rule, only the second grinding wheel 23 is vertically adjustable via the second grinding wheel shaft drive 29, so that the second grinding wheel 23 can be moved towards the loading plate 12 with the coil springs located therein.

[0040] The control unit 30 controls all movements, such as speeds, adjustment movements and sequences of the components of the spring end grinding device 1.

[0041] In the embodiment of Fig. Below the loading device 10, a discharge unit 40 is arranged, which has a shutdown module 41 that is operatively connected to the control unit 30. The shutdown module 41 serves to reliably shut down the spring end grinding device 1, in particular the loading device 10, in the event of a faulty discharge of a coil spring. After machining the coil springs, the surface-ground coil springs can be brought into a position by rotating the loading device 10 or the loading plate 12, in which the coil springs are discharged through an outlet opening 4 of the discharge unit 40 located below the loading device 10 (see also Fig. 4) fall downwards due to the action of gravity and can be collected by means of a container not shown and / or transported away by means of a suitable conveying device.

[0042] The shutdown module 41 is designed as a tactile flap 44 with sensor 42 (see also Fig. 6) designed, wherein the tactile flap 44 is rotatably or pivotally mounted about a circular pivot point. In the event that a spring inside the discharge unit 40 becomes jammed or an external intervention occurs, the tactile flap 44 would be actuated and, for example, activate a pressure safety sensor 43, which in turn sends a signal to the control unit 30 of the spring end grinding device 1 and ensures a safe shutdown. In addition to a pressure safety sensor 42, an inductive safety sensor 42 is also conceivable for this application.

[0043] The embodiment of Fig. Figure 2 shows a further advantageous device 1 for machining coil springs. This device operates according to the principle of the double-sided surface grinding process in a feed-in process (feed grinding). Essential components of the spring end grinding device 1 according to the embodiment shown in Figure 2 are shown. Fig. 2 are identical to those of the spring end grinding device 1 according to the embodiment according to Fig. 1.

[0044] The loading device 10 is rotatably mounted on the machine base 2 about the vertical axis 11. The grinding unit 20 is rotatably mounted on the machine base 2 about a grinding wheel axis 24, 25. The loading device 10 and the grinding unit 20 are spaced apart from each other on the machine base 2, with the vertical axis 11 of the loading device 10 and the grinding wheel axis 24, 25 of the grinding unit 20 being parallel to each other. The loading device 10 is positioned above a table 3 mounted on the machine base 2, the table 3 being rotatably mounted about the axis 11 in this embodiment. The loading device 10 further comprises two spaced-apart loading plates 12, 13, each rotatably mounted about two mutually parallel vertical axes 14, 15. The loading plate 12 is arranged to rotate about the axis 14 and the loading plate 13 is arranged to rotate about the axis 15.Furthermore, the loading device 10 has loading plate shafts 16, 17, which are driven by a drive motor (not shown). The loading plates 12, 13 arranged on the loading plate shafts 16, 17 can be driven by the control unit 30 in a rotary control manner. The rotational speed is adjustable depending on the application. The loading plates 12, 13 have spring receptacles 18 for the unloaded reception of coil springs. The spring receptacles 18 are located in the . Fig. 3 visible.

[0045] The coil springs located in the loading plates 12, 13 can be transferred from a loading position to a machining position, in which the coil springs are machined by a grinding unit 20. The one in the Fig. The loading plate 12 shown in Figure 2 is in a loading position, while the loading plate 13 is in the machining position within a grinding chamber 21 of the grinding unit 20. The grinding chamber 21 is shielded on the inside, i.e., on the side of the spring-end grinding device 1 facing the grinding chamber 21, by a grinding chamber cover 50 arranged on the machine base 2. This provides at least partial protection for the machine operator against sparks generated during machining and against grinding dust. At least part of the grinding chamber cover is height-adjustable.

[0046] The grinding unit 20 is analogous to the one in Fig. 1 grinding unit shown.

[0047] The control unit 30 controls all movements, such as speeds, adjustment movements and sequences of the components of the spring end grinding device 1.

[0048] Analogous to the embodiment of Fig. 1 is also in the embodiment of Fig. 2. A discharge unit 40 is arranged below the charging device 10, which has a shutdown module 41 that is operatively connected to the control unit 30. The function and design correspond to the discharge unit 40 according to the embodiment shown. Fig. 1 match.

[0049] Fig. Figure 3 shows a detailed view of the charging device 10 according to the embodiment of Fig. 2 with a tabletop 3 and loading plates 12, 13 located thereon, wherein the loading plates 12, 13 have spring receptacles 18 for receiving coil springs. The spring receptacles 18 are arranged eccentrically about the respective second and third vertical axes 14, 15. The spring receptacles 18 in the loading plates 12, 13 are through holes, so that the coil springs rest with their lower end faces on a surface of the tabletop 3. When the loading device 10 is rotated accordingly, it moves the coil springs located in the loading plates 12, 13 into a region of a tabletop recess 19 ( Fig. 4) The first grinding wheel 22 is located in this area of ​​the tabletop recess 19. The coil springs thus rest on the surface of the first grinding wheel 22 in this area and can be machined. Furthermore, Fig. 4 an outlet opening 4 incorporated into the table top 3 for unloading machined coil springs.

[0050] In Fig. Figure 5 is an oblique perspective view of a spring end grinding device 1 according to Fig. Figure 1 shows the process that uses continuous grinding. The essential components are the same as those of the Fig. 2. The basic functionality is also the same. The differences between continuous grinding and infeed grinding were already explained in the introductory description.

[0051] The embodiment of Fig. The loading device 10 comprises only a loading plate 12 centrally located on the tabletop 3, which is rotatable about the vertical axis 11, 14. In this case, the tabletop 3 is not rotatable about the vertical axis 11, 14 but is fixedly connected to the machine base 2.

[0052] The loading tray 12 can be manually loaded with coil springs from a front side of the spring end grinding device 1, which is easily accessible to the machine operator. It is advantageous to provide an automatic loading device (not shown) so that coil springs can be placed into the spring holders 18 of the loading tray 12, for example, using a robot manipulator. The loaded loading tray 12 rotates, for example, clockwise until the coil springs enter the grinding chamber 21 of the grinding unit 20 for machining. With further rotation, the loading tray 12 continues to rotate with the machined coil springs and passes the discharge opening 4 of the unloading unit 40.

[0053] For the embodiments according to Fig. 1 or Fig. 2. It is expedient to insert the shutdown module 41 into an outlet opening 4 of the discharge unit 40 molded into the tabletop 3. Fig. Figure 6 shows a section of the tabletop 3 with the shutdown module 41 inserted into the outlet opening 4. The shutdown module 41 has a mounting tab 43 at its upper end. The shutdown module 41 can be attached directly to the tabletop 3 using screws via the mounting tab 43 and corresponding threaded holes provided for this purpose. At its opposite lower end, the shutdown module 41 has the pressure safety sensor 42.

[0054] In the side view of the shutdown module 41 according to Fig.Figure 7 shows the tactile flap 44, which is hinged to a base body 46 of the shutdown module 41. The tactile flap 44 is pivotable about a pivot point 45. An actuating element 47 is arranged at a lower end of the tactile flap 44, which, when the tactile flap 44 is actuated and pivoted about the pivot point 45, triggers the pressure safety sensor 42. The shutdown module 41, which is operatively connected to the control unit 30, can thus ensure a safe shutdown of the spring-end grinding device 1, in particular of the at least one loading plate 12, in the event of a malfunction.

[0055] The advantage is that the shutdown module 41 can also be retrofitted and used for existing spring end grinding devices 1. Reference symbol list 1 Spring end grinding device 2 machine bases 3 Tabletop 4 Outlet opening 10 Charging device 11 first vertical axis 12 charging trays 13 charging trays 14 second vertical axis 15 third vertical axis 16 Loading plate shaft 17 Loading plate shaft 18 Spring mount 19 Tabletop recess 20 grinding units 21 Grinding room 22 first grinding wheel 23 second grinding wheel 24 first grinding wheel axis 25 second grinding wheel axis 26 first grinding wheel shaft 27 second grinding wheel shaft 28 first grinding wheel shaft drive 29 second grinding wheel shaft drive 30 control unit 40 discharge units 41 Shutdown module 42 Sensor 43 Mounting tab 44 tactile flap 45 pivot point 46 Basic bodies 47 Actuating element 50 Grinding chamber cover QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] EP 2 926 948 B1

[0016] DE 10 2020 205 721 B4

[0017]

Claims

[1] Device for machining coil springs, comprising: - a machine body (2) with a table top (3), - a loading device (10) arranged on the table top (3) and rotatable about a first vertical axis (11) with at least one rotatable loading plate (12, 13) with a plurality of spring receptacles (18) which are arranged eccentrically to the first vertical axis (11) and are each designed to receive a coil spring; - a grinding unit (20) forming a grinding chamber (21) into which the at least one loading plate (12, 13) can be transferred from a loading position to a machining position; - a discharge unit (40) arranged on the table top (3) outside the grinding chamber (21) for discharging the coil springs after their machining; and - a unit (30) for controlling the device during the machining of the coil springs; characterized by, - that the discharge unit (40) has a shutdown module (41) that is operatively connected to the control unit (30). [2] Device according to claim 1, characterized by , that the shutdown module (41) can be inserted into an outlet opening (4) of the discharge unit (40) molded into the table top (3). [3] Device according to claim 2, characterized by , that the outlet opening (4) is circular, rectangular or trapezoidal in shape. [4] Device according to claim 1, characterized by , that the discharge unit (40) is designed as a separate module and can be attached below the at least one loading plate (12, 13), wherein the module has a container open at two opposite end faces for arranging the shutdown module (41). [5] Device according to any one of the preceding claims, characterized by , that the shutdown module (41) is designed as a tactile flap with sensor (42). [6] Device according to claim 5, characterized by , that the sensor (42) is designed as a pressure safety sensor or as an inductive safety sensor. [7] Device according to any one of the preceding claims, characterized by , that the shutdown module is designed in such a way that the charging device (10) can only be loaded when the shutdown module (41) is installed. [8] Device according to any one of claims 1 to 7, characterized by , that the grinding unit (20) has a pair of grinding wheels with two rotatably mounted and separately driveable grinding wheels (22, 23), of which a first (22) is arranged above and a second (23) below the loading device (10). [9] Device according to any one of claims 1 to 8, characterized by , that the loading device (10) has only one loading plate (12) rotatable about the first vertical axis (11). [10] Device according to any one of claims 1 to 8, characterized by, that the loading device (10) has a first loading plate (12) rotatable about a second vertical axis (14) and a second loading plate (13) rotatable about a third vertical axis (15), each of which two loading plates (12, 13) are each provided with a plurality of spring receptacles (18) which are each arranged eccentrically to the second (14) and third vertical axis (15) and are each designed to receive a coil spring.

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