Solenoid actuator, use of a solenoid actuator and braking or clamping device for linearly moving and/or axially rotating components

The invention relates to a solenoid actuator, consisting of a magnet body (1), a magnet armature, a cover (3) closing the space in which the magnet armature travels back and forth, at least one electric coil (4), which is arranged in the magnet body (1) concentrically around the axis of travel of the magnet armature, and means (5) for power transmission, which are in operative connection with the magnet armature and protrude out of the solenoid actuator. According to the invention, the magnet armature of the solenoid actuator is an axially guided annular magnet armature (2), and the means (5) for power transmission are arranged coaxially around the axis of travel of the annular magnet armature (2). This has the advantage that the solenoid actuator allows long switching paths and a small construction, along with high tightening and holding forces. This also results in the up to 100% higher holding force of the solenoid, making it particularly suitable for the actuation of braking and clamping equipment for rods and cables.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is the National Stage of PCT/DE2012/000917 filed on Sep. 17, 2012, which claims priority under 35 U.S.C. §119 of German Application No. 10 2011 113 411.9 filed on Sep. 17, 2011, the disclosure of which is incorporated by reference. The international application under PCT article 21(2) was not published in English.

STATE OF THE ART

The invention proceeds from a solenoid actuator according to the type of claim1, the use of a solenoid actuator according to the type of claim6, and a braking or clamping device for linearly moved and/or axially rotating components according to the type of claim8.

Safety systems for braking and/or clamping linearly moved and/or axially rotating components, for example cables and rods, such as those offered for sale by the company Chr. Mayr GmbH & Co. KG, among others, are known. These safety brakes, offered for sale under the name ROBA-linearstop, are driven hydraulically and pneumatically, as are all other clamping or braking systems offered for sale on the market worldwide. It is a disadvantage, in this connection, that the media required for this purpose generally have to be made available first, while electrical energy is generally present at the locations of use of the clamping and braking system and is furthermore cheaper than hydraulically or pneumatically produced pressure energy. Those costs that are caused by the absolutely tight design of the systems on site, to guarantee the safety requirements established for such safety brakes, are added to the high provisioning costs. Furthermore, the high maintenance expenditure, which hydraulic systems, in particular, require because of the regular oil changes that must be performed, is disadvantageous. During maintenance times of the braking system, the entire facility into which the maintenance system is integrated is shut down.

These disadvantages can be overcome by braking and clamping systems that have an electrically operated solenoid actuator as the setting element. Very high holding forces can be generated using magnetic clamps. It is disadvantageous, in this connection, that the armatures of the magnetic clamps are not able to overcome larger air gaps. In general, the maximal air gap amounts to approximately 1 mm. As a result, no greater setting paths can be traveled or bridged, either.

Relatively great air gaps can be overcome using lifting magnets. In the case of conventional lifting magnets or pulling magnets, a lifting armature is situated in their axial center, which is guided by an armature spindle (DE 74 06 334 U; DE 28 43 593; DE 195 37 656 A1). However, in order to implement greater forces, the construction of the magnet must also be designed to be correspondingly large. This in turn has the disadvantage that they require a large construction space, which is not available in the case of braking or clamping devices for linearly moved and/or axially rotating components or mechanical processes, for example

The Invention and its Advantages

In contrast, the solenoid actuator according to the invention, having the characterizing feature of claim1, has the advantage that it allows long switching paths and a small construction at high attraction and holding forces. In this way, it is particularly suitable for activation of braking and clamping technology of rods and cables.

This is achieved in that the magnet armature is an axially guided ring magnet armature and the means for power transmission are disposed coaxially around the lifting axis of the ring magnet armature. Its up to 100% higher holding force also results from this. The term ring magnet armature should be understood not just as a magnet armature that is in the shape of a circular ring in a top view. Instead, here the syllable “ring” refers to any possible close shape of a polygon.

According to an advantageous embodiment of the invention, the magnet armature is configured as a flat armature, with a significantly greater width, in comparison with its height, of its ring-shaped holding and adhesion surface. The flatter configuration of the armature permits an overall flatter construction of the solenoid actuator. By means of the combination of two magnet systems, a completely new magnet form has been created, which meets higher demands and can be universally used.

The high attraction and holding forces of the flat armature magnet are based on a precisely determined magnetic flow calculation and control electronics newly developed for this magnet design, which make it possible to generate more than one hundred times super-excitation in the magnet within a millisecond range, and thereby also to implement super-proportionally high attraction forces.

Furthermore, it has been shown that the new magnet form can also be used in all other application cases, in other words anywhere where high attraction and holding forces are required.

The braking or clamping device according to the invention, for linearly moved and/or axially rotating components, having the characteristics of claim8, has the advantage, as compared with hydraulically or pneumatically driven braking systems, that it works faster and with greater energy savings, and is practically maintenance-free. Furthermore, because of the lower equipment technology expenditure, it is more cost-advantageous not only for making the energy source available but also for the solenoid actuator, in terms of its production. This is achieved by means of the use of a solenoid actuator as a setting drive for the breaking system, the magnet armature of which is an axially guided ring magnet armature and in which the means for power transmission are disposed coaxially around the lifting axis of the ring magnet armature. In this connection, the solenoid actuator can not only trigger the braking or clamping process, but also lift a brake that is in effect. In the latter case, the solenoid actuator acts as a lifting device for current-free braking and/or clamping of rods, shafts or cables, with similarly good parameters as allowed by a hydraulic or pneumatic lifting device.

Further advantages and advantageous embodiments of the invention can be derived from the following description of the drawing and the claims.

DESCRIPTION OF THE EXEMPLARY EMBODIMENT

FIG. 1shows a solenoid actuator according to the invention, consisting of a magnet body1, which forms the magnet housing. In its lower region, there is a ring magnet armature2. Magnet body1and ring magnet armature2are closed off by a magnet cover3. In the magnet body1, a coil space4for accommodating electrical coils is provided concentrically around the lifting axis of the ring magnet armature2, shown as a dot-dash line. For power transmission to a setting means5, four dead-end bores are introduced into the ring magnet armature2, coaxial to its lifting axis (see top view), into each of which bores a pressure bolt6is loosely inserted. At their free end, in each instance, projecting out of the magnet body1, the pressure bolts6are connected with the setting means5, which is a pressure plate in the present example. In the region of the entry into and exit out of the magnet body1, in each instance, the pressure bolts6are guided in accommodations7in the magnet body1. As a result, and because of the mechanically uncoupled attachment of the guide bolts6in the ring magnet armature2, the armature, precisely linearly guided by the pressure bolts6, can always perform its work parallel to the armature counter-surface.

The basic structure of the solenoid actuator shown inFIGS. 1 and 2is that of a pot magnet as a lifting or pulling magnet having an axial passage bore8that is situated not only in the ring magnet armature2but also in the magnet lid3. The working stroke path of the ring magnet armature2is indicated with an arrow9. The air gap between the magnet body1and the ring magnet armature2was indicated with the reference number10. Either a rod, shaft or a cable can be passed through the aforementioned passage bores8. The working surfaces of the ring magnet armature2and of the armature counter-piece in the magnet body1are protected from outside influences by means of seals. In this connection, the shape of the magnet body1can be of different geometrical shapes. Such a solenoid actuator can be used for various switching functions that require high pushing and/or holding forces.

The second embodiment shown inFIG. 2shows a solenoid actuator also having a passage bore8that passes through it, in which two pressure pins are passed through the ring magnet armature2and the magnet cover3as setting means5, and connected with one another by way of a flange plate11. Spring packages12are disposed between the flange plate11and the magnet cover3, which packages activate an activation mechanism, not shown here, for example a braking mechanism for rods, shafts or cables.

FIG. 3shows a third embodiment of the solenoid actuator according to the invention in a sectional representation, the ring magnet armature2of which has a cylindrical elongated shape having a center bore. The magnet cover3is attached at the lower end of the solenoid actuator, by means of screws, on its housing. The components that correspond to the parts mentioned in the description ofFIGS. 1 and 2were provided with the same reference numbers. A bearing sleeve21, which protects the magnet from dirt and moisture, for one thing, and for another thing serves as a guide for the freely movable ring magnet armature2which has a slide bearing bushing in its center bore for this purpose, leads through the entire solenoid actuator. In the upper region of the magnet body1, bores are introduced coaxially to the lifting axis of the ring magnet armature2, which bores accommodate pressure pins22that sit loosely in dead-end bores of the ring magnet armature2with their one end, and act on a pressure spring, not shown here, with their free end that projects out of the magnet body1, which spring acts as a recovery spring for the ring magnet armature2.

FIG. 4shows a section through a braking device provided with a solenoid actuator according to the invention, which can be structured, for example, as a rod clamping device or brake or as a cable brake. The components that correspond to the parts mentioned in the description ofFIGS. 1 to 3were provided with the same reference numbers.

In such use, it is required that the part (rod, shaft or cable) to be braked or to be clamped is guided through the brake element. The braking force itself is generated, in this embodiment, by a pressure spring13. The solenoid actuator according to the invention is available as a lifting device for the pressure spring13, with its components described inFIGS. 1 and 2. So that the solenoid actuator can allow the force to act centrally on the pressure spring13, it is required that the rod, shaft or cable is also guided through the solenoid actuator. In order to be able to brake or clamp a rod, shaft or cable having a relatively small diameter, very great clamping forces by a clamping element14are required. The clamping element14is activated either by a lever system, not shown in any detail here, or by a wedge gear. In order for great forces to be able to become active here, their setting drive must also be able to travel a long path. Working strokes of 6 to 10 mm are possible with the solenoid actuator according to the invention.

Finally, inFIG. 5, a section through a braking system provided with a solenoid actuator according to the invention is shown, the activation means of which system are situated within the solenoid actuator. The components that correspond to the parts mentioned in the description ofFIGS. 1 and 2were provided with the same reference numbers. In addition to the components already mentioned, this representation shows the placement of a ring coil15in the coil space4of the solenoid actuator. The switching electronics16with the electrical connector17are also accommodated within the magnet body1. A rod18is passed through the solenoid actuator within the passage bore8. The setting means5connected with the magnet armature2are articulated onto a pressure plate19with their other end, which plate in turn stands in an operative connection with a clamping part20disposed coaxially around the rod18.

FIGS. 1 to 4show lifting axis L of the magnet armature2and show power transmission axes PT1and PT2of the means for power transmission. Axis L, axis PT1and axis PT2are different from each other and are separate from each other. Axis PT1is spaced from axis L by distance d1. Axis PT2is spaced from axis L by distance d2. Distance d1is shown to be the same as distance d2inFIGS. 1,2and4.

Distance d1is shown to be different from distance d2inFIG. 3. Both d1and d2are positive numbers greater than zero. Hence the means for power transmission are disposed concentrically around the lifting axis of the ring magnet armature.

All of the characteristics mentioned in the description, the following claims, and shown in the drawing can be essential to the invention both individually and in any desired combination with one another.

REFERENCE NUMBER LIST