HK1250091B - Energy accumulator for an on-load tap changer, and on-load tap changer comprising an energy accumulator - Google Patents

Description

The invention relates to an energy storage for a load switch and a load switch with an energy storage.

An energy storage device, often also called a power accumulator, is used in a stepped load switch with a driven shaft, a driving shaft, and a load switch to convert a continuous, slow rotational movement of the driven shaft, which is driven by a motor with constant speed, into a sudden, rapid rotational movement of the driving shaft that drives the load switch. Many energy storage devices are already known that enable the sudden rotational movement of the driving shaft by means of a storage spring. The principle is always the same: the driven shaft, driven by the motor with constant speed, winds up the storage spring until a maximum point is reached, and once this maximum point is exceeded, the storage spring suddenly unwinds, thereby driving the driving shaft in a sudden manner.

DE 28 06 282 B1, EP 0 355 814 A2, DE 10 2005 027 524 B3, DE 10 2005 027 527 B3, DE 10 2010 020 130 A1 and EP 2 760 034 A1 each describe a load step switch with an energy storage device comprising a storage spring, a gear, a housing for the gear, an eccentric, a winding slide and a snap slide. The gear comprises an input hub and an output hub. Because of these slides, such energy storage devices are also referred to as slide-type energy storage devices.

In these known clutch switches, the output shaft is fixedly connected to the input hub. The input hub is fixedly connected to the eccentric. The eccentric is positively connected to the winding slide. The storage spring rests between the winding slide and the impact slide. The winding slide and the impact slide can move back and forth independently of each other along a linear guide relative to the frame between two end positions. The impact slide is positively connected to the output hub.

Consequently, the eccentric forms a clamping element together with the winding slide, which is designed in such a way that it engages the storage element for clamping and then, when the input hub is rotated, clamps the storage element. The jump slide forms a releasing element, which is designed in such a way that it engages the output hub on the storage element and then, when the storage element is released, drives the output hub.

DE 10 2006 008 338 B3 and DE 10 2009 034 627 B3 each describe a load step switch with an energy storage device, which includes a storage spring, a gear mechanism, a frame for the gear mechanism, a drive element in the form of a gear with two axially projecting stop surfaces, and a crank with a crankpin. The gear mechanism includes an input hub and an output hub. Because of this crank, such energy storage devices are also referred to as crank energy storage units.

In these known load switch mechanisms, the output shaft is rotationally fixedly connected to the input hub. The input hub is rotationally fixedly connected to the drive element. The drive element and the crank can rotate relative to each other between a first end position and a second end position. The stop surfaces correspond to the crank such that the first stop surface rests against a first side of the crank in the first end position, and the second stop surface rests against a second side of the crank in the second end position, with these sides being opposite each other. Consequently, the drive element is form-locked connected to the crank in these end positions. The storage spring is pivotably mounted at one free end on the crankpin and pivotably rests at its fixed end on the frame. The free end can move back and forth along a linear guide relative to the fixed end between two end positions. The crank is coupled to the output hub.

Consequently, the crank together with the drive element forms a clamping element designed in such a way that it engages the storage element for clamping and then, when the input hub is rotated, clamps the storage element; and the crank forms a releasing element designed in such a way that it engages the storage element for driving the output hub and then, when the storage element is released, drives the output hub.

In this context, the invention proposes the objects of the independent claims. Advantageous developments and embodiments of the invention are described in the dependent claims.

The invention proposes an energy storage device according to claim 1.

As an example of a variable translation device, here a translation device with variable transmission is understood, meaning that its transmission depends on the angular position of the input shaft or on the angular position of its input side, which is coupled to the input shaft and in particular rigidly connected to it. The translation device can particularly be designed such that the transmission changes when the input shaft is rotated from a first angular position to a second angular position, becoming larger or smaller, changing sign, remaining the same, or becoming infinite.

In this context, the translation ratio of the transmission is exemplarily defined as ü = vE : vA, where vE is the input speed at which the input side of the transmission, coupled to the input shaft, moves, and vA is the output speed at which the output side of the transmission, coupled to the storage element, moves. For example, if the input and output sides of the transmission are rotatable, the transmission ratio can also be expressed exemplarily as ü = nE : nA, where nE is the input rotational speed of the input side, and nA is the output rotational speed of the output side. Consequently, a large or small transmission ratio ü means a low or high output speed vA = vE : ü.

The translation device of the proposed energy storage allows an oscillating pivoting movement of the output shaft between its first and second angular positions regardless of the rotation direction of the input shaft. Here, an "oscillating pivoting movement" refers to the output shaft initially rotating in a first direction from a given first angular position to a given second angular position when the input shaft is rotated in a first direction from a given first angular position by a given difference angle. Then, when the input shaft is subsequently rotated either in an opposite, second direction back to its initial angular position or further in the first direction by the difference angle, the output shaft rotates in an opposite, second direction from its second position back to its initial angular position.

Preferably, each proposed energy storage device comprises a tensioning element designed to engage the storage element and then tension the storage element upon rotation of the input hub; a releasing element designed to engage the storage element for driving the output hub and then drive the output hub upon release of the storage element; wherein the gear is designed such that during release and/or driving of the output hub, the tensioning element follows the releasing element at a desired and/or predetermined speed; and/or during release and/or driving of the output hub, the releasing element can be pressed or can press.

In this case, the translation tool allows a descendant of the tension element to move relative to the relaxation element at a desired and/or predetermined speed, which can be particularly greater than the speed during tensioning.

In case of a defect or blockage or inhibition of the storage element, or under operating conditions that are more difficult compared to normal operating conditions for the load step switch, or in overload situations, the release and/or driving of the output shaft may occur slower than under normal operating conditions, and possibly so slowly that the tensioning element catches up with the releasing element and acts on the storage element as during tensioning. In this case, the transmission means allows the releasing element to be pressed back by driving the output shaft directly and without delay via the tensioning element and the releasing element from the input shaft.

The tension element and the relaxation element can be designed in any desired manner, for example as in a sled energy storage or a crank energy storage.

Preferably, each proposed energy storage device comprises at least one crank coupled to the storage element and to the gear.

The crank particularly forms at least a part of the tension element and/or at least a part of the release element.

The proposed energy storage can be designed in any desired manner and may, for example, include at least one or no additional elastic storage element and/or at least one or no additional gear and/or at least one or no additional transmission means.

Each storage element can be designed in any desired manner, for example as a screw tension spring or screw compression spring or gas pressure spring or elastomer spring.

Each translation device can be trained in any desired manner and may, for example, include at least one gear with non-uniform and/or adjustable transmission, preferably designed as a curved gear, link gear, step gear, continuously variable transmission (CVT), flow gear, or a gear pair consisting of two elliptical gears.

It is preferably provided that the gear is designed such that, when the input hub is rotated in a first direction, the storage element is tensioned from a predetermined first angular position to a predetermined second angular position, while the output hub remains stationary; and the storage element is designed such that, when the input hub is rotated in this direction, it is released from the second angular position to a predetermined third angular position, thereby rotating the output hub from a first angular position to a second angular position.

In this rotation from the first to the second angular position, the output shaft is particularly in its first angular position.

It is preferably provided that the gear is designed such that when the input hub is rotated in this direction from the second to the third angular position and/or when relaxing, the transmission ratio of the transmission means is smaller than when tightening.

It is preferably provided that the gear unit is designed such that, when the input shaft is rotated in this direction from the first to the second angular position, the transmission ratio of the transmission means is greater than a predetermined threshold value; and/or when the input shaft is rotated in this direction from the second to the third angular position, the transmission ratio of the transmission means is less than this threshold value or than another predetermined threshold value.

It is preferably provided that the gear is designed such that when the input shaft is rotated in this direction, it blocks the output shaft when moving from the third angular position to a predetermined fourth angular position; and/or the gear is designed such that during this rotation from the third to the fourth angular position, the transmission ratio of the transmission means is infinite.

In this rotation, the gear blocks the output shaft, particularly in its second angular position.

It is preferably provided that the gear is designed such that, when the input hub is rotated in this direction, it does not tension the storage element when moving from a predetermined fifth angular position, which is located before the first angular position, to the first angular position, and during this movement, the output hub remains stationary.

In this rotation, the initial hub is particularly in its first angular position.

It is preferably provided that the gear is designed such that, when the input shaft is rotated in this direction, it blocks the output shaft from the fifth angular position to a predetermined intermediate angular position located between the fifth and first angular positions; and/or the gear is designed such that, during this rotation from the fifth angular position to the intermediate angular position, the transmission ratio of the transmission means is infinite.

In this rotation, the gear blocks the output shaft, especially in its first angular position.

It is preferably provided that the gear is designed such that, when the input shaft is rotated in this direction from the fifth angular position or a predetermined intermediate angular position lying between the fifth and first angular positions to the first angular position, the gear ratio of the gear mechanism is smaller than during engagement.

It is preferably provided that the gear unit and the storage element are designed such that, when the input flange is rotated in this direction from the second angular position to the third angular position, they can rotate the output flange from its first angular position or from an intermediate angular position located between its first and second angular positions into its second angular position; or that the gear unit is designed such that, when the input flange is rotated in this direction from the second to the third angular position, it can rotate the output flange from its first angular position or from an intermediate angular position located between its first and second angular positions into its second angular position instead of the storage element.

It is preferably provided that the gear is designed in such a way that when the input shaft is rotated in this direction and between the second and third angular positions, it prevents the output shaft from moving away from its second angular position by more than a predetermined deviation angle.

It is preferably provided that the gear comprises at least one cam disc including at least one curve and the input hub; at least one sensor for scanning the curve; and/or the gear comprises a drive gear with a pivot axis, which carries the sensor radially offset relative to the pivot axis; and/or a driven gear including the output hub and coupled to the storage element; and/or a first, in particular freewheel-type clutch with a predetermined first angular clearance, which is interposed between the drive gear and the storage element; and/or a second, in particular freewheel-type clutch with a predetermined second angular clearance, which is interposed between the storage element and the driven gear.

Both the driving gear and the driven gear can be replaced, if necessary, by another suitable gear element, such as a sprocket or a pulley.

It is preferably provided that the gear comprises at least one locking mechanism coupled to the output shaft and in particular to the driven gear; the locking mechanism being designed such that, when the input shaft is rotated in this direction and between the second and third angular position, it prevents the output shaft from leaving its second angular position by more than the deviation angle and/or towards its first angular position; and/or in the second angular position of the output shaft, prevents the output shaft from leaving the second angular position towards the first angular position; and/or in an intermediate angular position of the output shaft, which lies between its first and second angular position, prevents the output shaft from leaving this intermediate angular position towards the first angular position; and/or when the output shaft is rotated from its second into its first angular position, prevents the output shaft from remaining in its intermediate angular position.

It is preferably provided that the gear comprises a first gear or A-gear meshing with the driving gear; and/or a second gear or B-gear which is particularly coupled to the A-gear, especially via the first clutch; and/or a third gear or C-gear which meshes particularly with the B-gear; and/or a fourth gear or D-gear which meshes with the driven gear and is particularly coupled to the C-gear, especially via the second clutch.

Each of these gears can be replaced by another suitable gear element if needed, for example, by a sprocket or a pulley.

Preferably, each proposed energy storage device comprises at least one crank coupled to the storage element and/or to the C-gear.

The crank particularly forms at least a part of the tensioning element and/or at least a part of the releasing element.

It is preferably provided that the gear comprises at least one release mechanism, which is particularly coupled to the B gear; the release mechanism being designed such that when the input hub is rotated in this direction and then, when the input hub is in the second angular position or between the second and third angular positions, it releases the locking mechanism.

It is preferably provided that the curve is shaped such that when rotating the input hub in a first direction from the fifth to the fourth angular position, and when rotating the input hub in an opposite, second direction from the fourth to the fifth angular position, the respective movements of the drive gear run symmetrically with respect to each other; and/or the curve is shaped such that when rotating the input hub in the first direction from the fifth to the fourth angular position, and when rotating the input hub in the first direction from the fourth angular position by the same difference angle, the respective movements of the drive gear run symmetrically with respect to each other; and/or the curve is closed upon itself; and/or the curve is shaped such that the difference angle between the fourth and fifth angular positions is 180°, or 90°, or 60°, or 45°, or an integer fraction of 180°.

The invention proposes, according to a second aspect, a load step switch comprising: a motor with an output shaft; a load switch with a drive shaft; an energy storage device designed according to the first aspect, wherein the input hub is rotationally fixedly connected to the output shaft, and the output hub is rotationally fixedly connected to the drive shaft.

The proposed load step switch can be configured in any desired manner and may, for example, include at least one or no additional motor and/or at least one or no additional load switch and/or at least one or no additional energy storage.

Each motor can be trained in any desired manner, for example as a motor with constant or unchangeable or unregulated speed. Preferably, the load step switch comprises at least one selector having a selector drive shaft which is rotationally connected to the output shaft or the output shaft itself. The selector preferably comprises at least two movable contact pieces which are rotationally connected to the selector drive shaft.

The explanations and elaborations regarding one aspect of the invention, in particular regarding individual features of this aspect, apply correspondingly also analogously to the other aspects of the invention.

The following describes example embodiments of the invention with reference to the accompanying drawings. The details in the drawings are intended for illustration only and should not be construed as limiting. The reference signs contained in the claims are not intended to limit the scope of protection of the invention, but merely refer to the embodiments shown in the drawings.

The drawings show in FIG. 1 a preferred embodiment of a load step switch with an energy storage; FIG. 2 a first view of a preferred embodiment of the energy storage of FIG. 1 with a locking mechanism in a first embodiment; FIG. 3 a second view of the energy storage from FIG. 2; FIG. 4 a third view of the energy storage from FIG. 2; FIG. 5 a fourth view of the energy storage from FIG. 2; FIG. 6 a fifth view of the energy storage from FIG. 2; FIG. 7 a cross-sectional view of an exemplary embodiment of a first coupling for the energy storage; FIG. 8 a cross-sectional view of an exemplary embodiment of a second coupling for the energy storage; FIG. 9 a partial view of an exemplary embodiment of a cam disk for the energy storage; FIG. 10 a second embodiment of the locking mechanism; FIG. 11 a third embodiment of the locking mechanism.

In FIG. 1, a preferred embodiment of a load step switch 10 is schematically shown, which includes, by way of example, a motor 11 with a driven shaft 12, a load switch 13 with a drive shaft 14, an energy storage 15, and a selector 16. The load switch 13 and the selector 16 are formed in a known manner and therefore are not shown in more detail. The selector 16 comprises several fixed contacts (not shown) and two movable contact elements (not shown), and is coupled to the driven shaft 12 for driving the contact elements. The load switch 13 comprises a movable switching contact unit (not shown) and is coupled to the drive shaft 14 for driving the switching contact unit. The drive shaft 14 is coupled to the driven shaft 12 via the energy storage 15, which is driven by the motor 11 at a constant rotational speed during a switching operation of the load step switch 10.

In FIG. 2, FIG. 3, FIG. 4, FIG. 5, and FIG. 6, a preferred embodiment of the energy storage unit 15 is schematically shown from different views. The energy storage unit 15 includes, by way of example, a gear unit, an elastic storage element 17, a crankshaft 18 that couples the storage element 17 to the gear unit, and a frame (not shown in FIGS. 3, 4, 5) comprising an upper and lower frame plate 19', 19" and braces connecting the frame plates 19. The storage element 17 is pivotably mounted on the frame plates 19 at a fixed end (left side in FIG. 2) and rotatably mounted on the crankshaft 18 at an opposite movable end (right side in FIG. 2).

The gear comprises, by way of example, a cam disk 20 (not shown in FIG. 5) having an input hub 201 and a key-shaped curve 202 (FIG. 3) on its underside, a sensor 21 (FIG. 3) that scans the curve 202, a driving gear 22 with a pivoting axis 221, a driven gear 23 with an output hub 231 and a flywheel mass 232, a first and second clutch 24, 25 (FIG. 2, 5, 6), a locking mechanism 26 in a first embodiment having a first and second pawl 261, 262 and a first and second latching notch 263, 264, an A-gear 27, a B-gear 28, a C-gear 29, a D-gear 30, as well as a release mechanism with a first and second release pin 31', 31".

The input shaft 201 is rotationally fixed connected to the output shaft 12 (not shown). The output shaft 231 is rotationally fixed connected to the input shaft 14 (not shown). The driving gear 22 carries the follower 21, which is radially offset relative to the pivot axis 221 and extends upward into the curve 202. Cam disc 20 and follower 21 together form a cam mechanism, which represents a variable transmission device interposed between the input shaft 201 and the storage element. The A-gear 27 meshes with the driving gear 23. The B-gear 28 is coupled to the A-gear 27 via the first clutch 24. The C-gear 29 meshes with the B-gear 28. The D-gear 30 is coupled to the C-gear 29 via the second clutch 25 and meshes with the output gear 23. The crankshaft 18 is rotationally fixed connected to the C-gear 29. Thus, the driving gear 22 is connected via the A-gear 27, first clutch 24, B-gear 28, C-gear 29 and crankshaft 18 to the storage element 17. The output gear 23 is thus connected via the D-gear 30, second clutch 25, C-gear 29 and crankshaft 18 to the storage element 17.

The drive gear 23 is located below the lower frame plate 19", and the flywheel mass 232 is attached to the bottom side of its teeth. Each latch 261, 262 is pivotably mounted on the top side of the flywheel mass 232, radially outside the teeth, and has at its radially outer free end a latch claw for engaging the associated locking nose 263, 264 when latching, whereas its radially inner free end serves as a stop for the associated release pin 31', 31" during unlatching. The locking noses 263, 264 are fixed to the bottom side of the lower frame plate 19", radially outside the latches 261, 262, and each has a flat radially inward extending bearing surface and a steep radially outward extending locking surface.It connects at the radially inner end of the support surface. The release bolts 31', 31" are fixed to the B gear 28 and extend through a curved slot in the lower frame plate 19" downward to the level of the associated latch 261, 262. By appropriately rotating the B gear 28, each release bolt 31', 31" can be moved to disengage against the inner free end of the corresponding latch 261, 262, thereby pivoting the latch's claw radially inward from the respective detent nose 263, 264 against the preloading force of an associated preloading spring, which is supported on the flywheel mass 232.

In FIGS. 7 and 8, exemplary embodiments of the first or second coupling 24, 25 are shown in a cross-section perpendicular to the respective axis of rotation in a schematic representation. The couplings 24, 25 are each overrunning clutches and designed in the manner of a claw clutch, and each have a predetermined first or second angular clearance, which allows an overrunning movement limited accordingly in each rotational direction.

The first clutch 24 (FIG. 7) comprises a first clutch jaw 24' with a first and second abutment surface 241 (FIG. 5, 6), 242, and a second clutch jaw 24" with a third and fourth abutment surface 243, 244 (FIG. 5). The first clutch jaw 24' is attached to the bottom of the A gear 27, and the second clutch jaw 24" is attached to the top of the B gear 28.

The operation of the first clutch 24 is as follows: When the A gear 27 is rotated clockwise from the position shown in FIG. 5, the first clutch jaw 24' is also rotated clockwise as shown in FIG. 7. FIG. 7 shows an intermediate position in which the abutment surface 241 has not yet come into contact with the abutment surface 243, and therefore the second clutch jaw 24" and the B gear 28 remain stationary. Once the A gear 27 and the clutch jaw 24' have been rotated sufficiently so that the abutment surface 241 comes into contact with the abutment surface 243, the B gear 28 is then also rotated clockwise from the position shown in FIG. 5 via the second clutch jaw 24". When the A gear 27 is then rotated counterclockwise, the clutch jaw 24' is also rotated counterclockwise. Initially, the abutment surface 242 does not yet come into contact with the abutment surface 244, and thus the second clutch jaw 24" and the B gear 28 remain stationary. Once the A gear 27 and the clutch jaw 24' have been rotated sufficiently, namely by the first backlash angle, so that the abutment surface 242 comes into contact with the abutment surface 244, the B gear 28 is then also rotated counterclockwise during further rotation. The operation when driving the B gear 28 is correspondingly reversed.

The second clutch 25 (FIG. 8) comprises a first clutch jaw 25' with a first and second abutment surface 251 (FIG. 2), 252 (FIG. 2, 5) and a second clutch jaw 25" with a third and fourth abutment surface 253, 254. The first clutch jaw 25' is attached to the C gear 29 and the second clutch jaw 25" is located on the top of the D gear 30. The operation of the second clutch 25 corresponds to that of the first clutch 24.

FIG. 9 is a sub-view of the cam disk 20 from FIG. 4, showing an exemplary embodiment of the curve 202. Curve 202 is closed on itself and includes a first section 202A with a constant first radius, a second section 202B with a constant second radius smaller than the first radius, a third section 202C connecting the lower ends of sections 202A and 202B and having a variable radius, and a fourth section 202D connecting the upper ends of sections 202A and 202B and having a variable radius; the radii refer to the input hub 201. Thus, curve 202 provides a variable gear ratio.

The operation of the variable transmission ratio gear mechanism formed by the cam drive is as follows: As an example, the A-basic position shown in FIGS. 3 to 6 is taken as a starting point, in which the cam disc 20 assumes the position shown in FIG. 9, corresponding to a fifth angular position α5 = 0°, the sensor 21 is located in section 202A (FIG. 3, 4), the stop surface 242 rests against the stop surface 244, and consequently the stop surface 241 is completely separated from the stop surface 243 by the entire first play, the stop surface 252 rests against the stop surface 254, and consequently the stop surface 251 is completely separated from the stop surface 253 by the entire second play, the memory element 17 is relaxed, and the latch 261 is engaged with the detent nose 263 and the latch 262 is disengaged. The endpoint will be a B-basic position, in which the cam disc 20 assumes a fourth angular position α4 = 180°, the sensor 21 is located in section 202B, the stop surface 241 rests against the stop surface 243, and consequently the stop surface 242 is completely separated from the stop surface 244 by the entire first play, the stop surface 251 rests against the stop surface 253, and consequently the stop surface 252 is completely separated from the stop surface 254 by the entire second play, the memory element 17 is relaxed, and the latch 262 is engaged with the detent nose 264 and the latch 261 is disengaged.

When motor 11 rotates the cam disc 20 via the output shaft 12 and input hub 201 from this A-basic position, i.e., from the fifth angular position a5, in a first direction R1 to a first angular position α1, the sensor 21 initially moves from section 202A towards section 202C and then continues moving into section 202C. Since the radius of the curve 202 is constant in section 202A, the drive gear 22 is not moved, which corresponds to an infinite transmission ratio of the cam drive. As a result, the gear blocks an unwanted rotation of the output gear 23 driven by the drive shaft 14. In section 202C, the radius initially decreases rapidly, corresponding to a small transmission ratio. Consequently, the drive gear 22 and the A-gear 27 are rotated quickly until, at angular position α1, the first backlash is completely used up, so that now the abutment surface 241 contacts the abutment surface 243, and thus the abutment surface 242 is now completely separated from the abutment surface 244 by the entire first backlash. Therefore, during this rotation from angular position α5 to angular position α1, the B-gear 28 and the subsequent gear train are not driven, so that the storage element 17 is not tensioned and the output hub 231 remains stationary.

When motor 11 turns the cam disc 20 from angular position α1 further towards direction R1 until a second angular position α2, the sensor 21 moves further in section 202C towards section 202B. Since the radius in section 202C now decreases more slowly than before, this corresponds to a larger gear ratio. Consequently, the drive gear 22 and the A-gear 27 are rotated more slowly. Through the first clutch 24, the B-gear 28, the C-gear 29, and the crankshaft 18 are also rotated, thereby tensioning the storage element 17 until, at angular position α2, the storage element 17 is tensioned up to its upper dead center, and the second play is exhausted, so that the contact surface 251 now rests against the contact surface 253, and thus the contact surface 252 is now completely separated from the contact surface 254 by the entire second play. As a result, during this rotation from angular position α1 to angular position α2, the D-gear 30 and the subsequent gear train are not driven, so that the output hub 231 remains stationary. The B-gear 28 moves the release pin 31' until it reaches the stop of the first detent 261.

When motor 11 further rotates the cam disc 20 from angular position α2 in the direction of R1 until reaching a third angular position α3, the sensor 21 moves further in section 202C up to section 202B. Consequently, the release pin 31' is pressed by the B gear 28 against the latch 261, thereby disengaging it from the detent nose 263. At the same time, the crank 18 pushes the memory element 17 beyond the top dead center, so that the memory element 17 relaxes and thereby turns the output gear 23 from the first angular position ω1 shown in FIGS. 2 to 6 into a second angular position ω2. In angular position ω1, the flywheel mass 232 has its right end shown in FIG. 6 resting against a front stop block located in FIG. 6, which is attached to the underside of the lower frame plate 19". In angular position ω2, the flywheel mass 232 has its left end shown in FIG. 6 resting against a rear stop block located in FIG. 6, which is attached to the underside of the lower frame plate 19", the latch 262 is engaged with the detent nose 264, and the latch 261 is disengaged.

When motor 11 rotates the cam disk 20 further from angular position α3 towards direction R1 until reaching the fourth angular position α4, which corresponds to the B-base position, the follower 21 moves into section 202B. Since the radius of the curve 202 is constant in section 202B, the driving gear 22 is not moved, corresponding to an infinite transmission ratio of the cam drive. As a result, the gear blocks an unwanted rotation of the driven gear 23 driven by the driving shaft 14.

Curve 202 is designed in such a way that, both when the input hub 201 is rotated as previously explained in the first direction R1 from angular position α5 to angular position α4, and also when the input hub 201 is further rotated in an opposite, second direction R2 from angular position α4 back to angular position α5, the respective movements of the drive gear 22 take place in a mirror-like manner relative to each other; and both when the input hub 201 is rotated as previously explained in direction R1 from angular position α5 to angular position α4, and also when the input hub 201 is rotated further in direction R1 from angular position α4 by the same difference angle, which is exemplarily α4 - α5 = 180°, the respective movements of the drive gear 22 again take place in a mirror-like manner relative to each other.

In normal operation, the storage element 17 relaxes quickly and with such force that the C gear 29 rotates so fast that it turns the B gear 28 faster than the driving gear 22 turns the A gear 27. Consequently, the contact surface 241 moves away from the contact surface 243, allowing the clutch 24 to run freely again. In order to achieve a prompt re-pressing of the driven gear 23 by the motor 11 in case the storage element 17 cannot rotate the driven gear 23 quickly enough, the radius now decreases more rapidly in section 202C, which means a smaller gear ratio and faster rotation of the driving gear 22 and the driven gear 23. Consequently, in this case, the transmission can rotate the driven gear 23 from angular position ω1 or from an intermediate angular position between angular positions ω1 and ω2 into angular position ω2, using the motor 11 either together with the storage element 17 or even instead of the storage element 17.

In FIG. 10, a second embodiment of the locking mechanism 26 is schematically shown. This embodiment is similar to the first embodiment, so the following mainly explains the differences. Locking projection 264 is designed similarly to locking projection 263 and is not shown.

In this embodiment, the first locking nose 263 has an intermediate locking surface 32 on its bearing surface, between its locking face and its opposite end, which engages the latch 261 with its latch claw when the driven gear 23 reaches a corresponding intermediate angular position while rotating from angular position ω1 to angular position ω2, which lies between these angular positions ω1 and ω2. Consequently, the locking mechanism 26 prevents the driven gear 23 from leaving this intermediate angular position towards its initial angular position ω1.

In this embodiment, the locking mechanism 26 comprises a first spring plate 265 assigned to the latch nose 263, a second spring plate (not shown) assigned to the latch nose 264, and two guiding pins 266, 267 assigned to the latches 261, 262. The first spring plate 265 is fixed at one end (on the left in FIG. 10) radially inside its latch nose 263 on the underside of the lower frame plate 19" and presses with its other free end (on the right in FIG. 10) radially outward against the connecting edge between the support surface and the latch surface. The fixed end is located in the area of the intermediate latch surface 32. Each guide pin 266, 267 is located on the top side of the claw of its associated latch 261,262 is secured. When the latch 261 is engaged, the guide pin 266 in FIG. 10 is guided from left to right into the space between the spring plate 265 and the catch nose 263 until the driven gear 23 reaches its second angular position ω2 shown in FIG. 10, in which the latch 261 is engaged and the guide pin 266 has left the space. During disengagement, the guide pin 266 is moved radially inward past the free end of the spring plate 265 and, during further rotation of the driven gear 23, slides along the side of the spring plate 265 facing away from the catch nose 263 toward the first angular position ω1 in FIG.10 from right to left and prevents the handle 261 from engaging the intermediate stop surface 32 with its handle claw. Consequently, the locking mechanism 26 prevents the driven gear 23, when rotating from angular position ω2 to angular position ω1, from remaining in this intermediate angular position or getting stuck.

In FIG. 11, a third embodiment of the locking mechanism 26 is schematically shown. This embodiment is similar to the second embodiment, so the following mainly explains the differences. The detent nose 264 is designed similarly to the detent nose 263 and is not shown.

In this embodiment, the locking mechanism 26 includes a first cover part 268 assigned to the latching nose 263 and a second cover part assigned to the latching nose 264 (not shown) instead of the spring plates 265, 266. Compared to the second embodiment, the intermediate latching surface 32 is closer to the latching surface and is not visible because it is covered by the cover part 268. The cover part 268 is preloaded by a biasing spring that is supported on the radially outer surface of the latching nose 263, and is biased radially outward at its right end in FIG. 11 against the junction between the supporting surface and the latching surface. The cover part 268 is located with its other end, which is shown in FIG.11. At the left end, with a distance from the latch nose 263. When the lever 261 is engaged, the guide pin 266 is guided from left to right in FIG. 11 into the space between the cover part 268 and the latch nose 263 until the driven gear 23 reaches its second angular position ω2 shown in FIG. 11, in which the lever 261 is engaged and the guide pin 266 has left the space. During disengagement, the guide pin 266 is moved radially inward past the free end of the cover part 268 and, during further rotation of the driven gear 23, slides along the side of the cover part 268 opposite the latch nose 263 toward the first angular position ω1 in FIG.11 from right to left and prevents the handle 261 from engaging the intermediate stop surface 32 with its handle claw. Consequently, the locking mechanism 26 prevents the driven gear 23, when rotating from angular position ω2 to angular position ω1, from remaining, getting stuck or jamming in this intermediate angular position.

REFERENCE MARK

10 Load switch 11 Motor 12 Output shaft 13 Load reversing switch 14 Drive shaft 15 Energy storage 16 Selector 17 Elastic storage element 18 Crank 19'/19" upper/lower frame plate 20 Cam 201/202 Input flange / curve of 202 202A/B/C/D first/second/third/fourth section of 202 21 Tapper 22 Drive gear 221 Swivel axis of 22 23 Driven gear 231/232 Output flange / flywheel of 23 24 First clutch 24'/24" first/second clutch jaw of 24 241/242 first/second stop surface of 24 243/244 third/fourth stop surface of 24 25 Second clutch 25'/25" first/second clutch jaw of 25 251/252 first/second stop surface of 25 253/254 third/fourth stop surface of 25 26 Locking mechanism 261/262 first/second catch of 26 263/264 first/second locking notch of 26 265 first spring leaf of 26 266/267 first/second guide pin of 26 27 A-gear 28 B-gear 29 C-gear 30 D-gear 31'/31" first/second release pin 32 Intermediate stop surface of 26, 264 R1/R2 first/second rotation direction of 20 α1...α5 angular positions of 20 and 201 ω1, ω2 angular positions of 23 and 231

Claims (13)

1. An energy accumulator (15) for an on-load tap changer (10) that comprises a motor (11) with an output shaft (12) and a load diverter switch (13) with an input shaft (14), the energy accumulator (15) comprising

   - an elastic storage element (17);

   - a gear that is coupled to the storage element (17) and comprises

   • an input hub (201) that can be non-rotatably connected to the output shaft (12);

   • an output hub (231) that can be non-rotatably connected to the input shaft (14); and

   • a variable transmission means (20, 21) that is interposed between the input hub (201) and the storage element (17); characterised by

   • a first coupling (24) with a specified first angular backlash, which first coupling (24) is interposed between the input hub (201) and the storage element (17);

   • a second coupling (25) with a specified second angular backlash, which second coupling (25) is interposed between the storage element (17) and the output hub (231).
2. The energy accumulator (15) according to one of the previous claims, comprising

   - a tensioning element (18) that is formed such that it engages at the storage element (17) for tensioning and then tensions the storage element (17) upon rotation of the input hub (201);

   - a relaxing element (18) that is formed such that it engages at the storage element (17) for driving the output hub (231) and then drives the output hub (231) upon relaxation of the storage element (17); wherein

   - the gear is formed such that it

   • follows up the tensioning element (18) to the relaxing element (18) at a specified velocity upon relaxation; and/or

   • re-presses the relaxing element (18) upon relaxation.
3. The energy accumulator (15) according to one of the previous claims, wherein

   - the gear is formed such that it

   • tensions the storage element (17) upon rotation of the input hub (201) in a first direction (R1) from a specified first angular position into a specified second angular position, and the output hub (231) meanwhile stands still;

   - the storage element (17) is formed such that it

   • relaxes upon rotation of the input hub (201) in said direction (R1) from the second angular position into a specified third angular position, and the output hub (231) meanwhile rotates from a first angular position into a second angular position.
4. The energy accumulator (15) according to claim 3, wherein

   - the gear is formed such that

   • the transmission of the transmission means (20, 21) upon rotation of the input hub (201) in said direction (R1) from the second into the third angular position is smaller than during tensioning.
5. The energy accumulator (15) according to claim 3, wherein

   - the gear is formed such that

   • the transmission of the transmission means (20, 21) upon rotation of the input hub (201) in said direction (R1) from the first into the second angular position is greater than a specified threshold value;

   • the transmission of the transmission means (20, 21) upon rotation of the input hub (201) in said direction (R1) from the second into the third angular position is smaller than the threshold value.
6. The energy accumulator (15) according to claim 3, wherein

   - the gear is formed such that it

   • blocks the output hub upon rotation of the input hub (201) in said direction (R1) from the third angular position into a specified fourth angular position.
7. The energy accumulator (15) according to claim 6, wherein

   - the gear is formed such that it

   • does not tension the storage element (17) upon rotation of the input hub (201) in said direction (R1) from a specified fifth angular position, which is located before the first angular position, into the first angular position, and the output hub meanwhile stands still.
8. The energy accumulator (15) according to claim 3, wherein

   - the gear and the storage element (17) are formed such that together they

   • rotate or can rotate the output hub (231) from its first angular position or from an intermediate angular position, which is located between its first and second angular position, into its second angular position upon rotation of the input hub (201) in said direction (R1) from the second angular position into the third angular position;

   - and/or the gear is formed such that

   • instead of the storage element (17), the gear rotates or can rotate the output hub from its first angular position or from an intermediate angular position, which is located between its first and second angular position, into its second angular position upon rotation of the input hub (201) in said direction (R1) from the second into the third angular position.
9. The energy accumulator (15) according to claim 3, wherein

   - the gear is formed such that it

   • prevents the output hub (231) from being able to depart from its second angular position by more than a specified deviation angle upon rotation of the input hub (201) in said direction (R1) and between the second and third angular position.
10. The energy accumulator (15) according to claim 3, wherein

    - the gear comprises

    • a locking mechanism (26) that is coupled to the output hub (231);

    - the locking mechanism (26) is formed such that it

    • prevents the output hub (231) from being able to depart from its second angular position by more than the deviation angle and/or toward its first angular position upon rotation of the input hub (201) in said direction (R1) and between the second and third angular position;

    • prevents the output hub (231) from being able to depart from its second angular position toward its first angular position when the output hub (231) is in the second angular position;

    • prevents the output hub (231) from being able to depart from an intermediate angular position toward its first angular position when the output hub (231) is in said intermediate position, which is located between its first and second angular position;

    • prevents the output hub (231) from remaining in its intermediate angular position upon rotation of the output hub (231) from its second into its first angular position.
11. The energy accumulator (15) according to claim 3, wherein

    - the gear comprises

    • a release mechanism ;

    - the release mechanism is formed such that it

    • releases the locking mechanism (26) upon rotation of the input hub (201) in said direction (R1) and in the second angular position or between the second and third angular position.
12. The energy accumulator (15) according to claim 7, wherein

    - the gear comprises

    • a cam disk (20) that comprises a cam (202) and the input hub (201);

    • a cam follower (21) that follows the cam (202);

    - the cam (202) is formed such that each of the particular movements of the cam follower (21) run mirror-invertedly to each other upon rotation of the input hub (201) in the first direction (R1) from the fifth into the fourth angular position and upon rotation of the input hub (201) in an opposite, second direction (R2) from the fourth into the fifth angular position; and/or

    - the cam (202) is formed such that each of the particular movements of the cam follower (21) run mirror-invertedly to each other upon rotation of the input hub (201) in the first direction (R1) by a differential angle from the fifth into the fourth angular position and upon rotation of the input hub (201) in the first direction (R1) by the same differential angle from the fourth angular position; and/or

    - the cam (202) is in itself closed; and/or

    - the cam (202) is formed such that the differential angle between the fourth and fifth angular position is 180° or 90° or 60° or 45° or a whole-number fraction of 180°.
13. An on-load tap changer (10) comprising

    - a motor (11) with an output shaft (12);

    - a load diverter switch (13) with an input shaft (14);

    - an energy accumulator (15) that is formed according to one of the previous claims; wherein

    - the input hub (201) is non-rotatably connected to the output shaft (12);

    - the output hub (231) is non-rotatably connected to the input shaft (14).