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(11) | EP 0 051 377 B1 |
| (12) | EUROPEAN PATENT SPECIFICATION |
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| (54) |
Exercise apparatus Übungsgerät Appareil d'exercice |
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| Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention). |
[0001] This invention relates generally to exercise apparatus for use by human beings for physiological conditioning and pertains more particularly to movable structures which provide a resistance force which is electrically controllable.
[0002] One prior art weight training apparatus is disclosed by Bradley in U.S. Patent 4,138,106. Bradley discloses the use of an electrical rewind motor to control the restraining effect on a cable reel which is connected, through cables, to a lifting bar.
[0003] Another type of prior art exercise apparatus is disclosed by Jungreis in U.S. Patent 3,731,922, entitled "Method of Isotonic Exercise". Jungreis discloses the use of an electric motor to slidably move a weight along a beam in order to vary the force on the muscles of the user.
[0004] Various combinations of mechanical elements have been used in the past to construct exercise devices. Levers, weights, cables, and pulleys are among the elements which have been combined in various ways to produce exercise apparatus.
[0005] From French Patent Specification No. FR-A-2 045 215, there is also known an exercise comprising a member mounted on a base and movable relative thereto through a plurality of ranges of angular orientation relative to the base, the member being positioned to be manipulated by an operator, and a magnetic brake mounted on the base for providing a resistance to movement of the member relative to the base, the resistance being approximately proportional to the magnitude of the electrical current supplied to the magnetic brake, and an electrical control device for varying the magnitude of the current supplied to the magnetic brake.
[0006] However, the latter device has the disadvantage that the level of force is constant in each direction of movement of the angularly movable member.
[0007] There remains a requirement for a low cost, lightweight, portable, adjustable exercise apparatus for which the magnitude of resistance force may be precisely and selectively controlled across its ranges of movement.
[0008] According to the present invention, there is provided an exercise apparatus, comprising a member mounted on a base and movable in forward and reverse directions through a plurality of ranges of movement relative to the base, the member being positioned to be moved in the forward and reverse directions by an operator for exercising, and a magnetic brake mounted on the base for providing a resistance force to relative movement of the member and the base, the resistance being approximately proportional to the magnitude of the electric current supplied to the magnetic brake, and wherein the exercise apparatus comprises an electrical commutator switch assembly attached to the base, including a plate having a plurality of electrically conductive sector pads mounted along a path thereon, the sector pads defining ranges in the movement of the member with respect to the base; a wiper mounted on the member and having sequential electrical contact with each of the sector pads as the member is moved relative to the base; first and second sets of electrical resistors, each set including a plurality of electrical resistors having variable resistance, wherein one resistor of each set is selectively connected to one of the sector pads, and wherein the resistance of each of the variable resistors is independently adjustable; a first end electrical contact mounted on the base so as to be contacted by the wiper when the member is at the end of its movement in the reverse direction, and a second end electrical contact mounted on the base so as to be contacted by the wiper when the member is at the end of its movement in the forward direction, wherein when the wiper contacts the first end electrical contact the resistors of the first set of resistors are connected to the sector pads, and when the wiper contacts the second end electrical contact the resistors of the second set of resistors are connected to the sector pads so that when the member is rotated in the forward direction to move the wiper from the first end contact to the second end contact, the first set of resistors is connected to the sector pads, and as the member is rotated in the reverse direction to move the wiper from the second end contact to the first end contact the second set of resistors is connected to the sector pads; and a power supply connected to the magnetic brake, to the wiper, and to the variable resistors so that when the wiper contacts one of the sector pads a circuit is formed to supply a current to the magnetic brake, wherein the magnitude of the current is controlled by the variable resistance of the resistor connected to the contacted sector pad.
[0009] The exercise apparatus of this invention may form a therapy table for use in the physiological conditioning of human beings. The apparatus may be of lightweight and compact construction.
[0010] The therapy table exercise apparatus provides a resistance force to movement by a user in which the magnitude of the resistance force is electrically controllable.
[0011] The apparatus of this invention may produce a resistance force in use which varies with the position of a manipulated bar and with the direction of movement of the bar.
[0012] A preferred apparatus of this invention comprises a member such as a holder bar rotatably mounted on a base which may be in the form of a bench or table. The holder bar is designed to be grasped by the user and resistance to the rotation of the holder bar is provided by an electrically controlled brake. The braking force provided by the brake is adjustable, such as by potentiometers, to control the magnitude of the braking force over separate regions in the range of movement of the holder bar. Means such as switches and a relay are provided to sense the direction of movement of the holder bar and to vary the braking force in accordance with the direction of movement of the holder bar. Means such as commutator switch is provided to detect the rotational position of the holder bar and to reverse the forces when the rotational direction is transversed. Thus means may be provided in the apparatus for automatically varying the braking force in response to the angular orientation of the member or bar on the base.
[0013] Some preferred embodiments of the invention will now be more particularly described with reference to the accompanying drawings, wherein like reference characters refer to the same or similar parts throughout the several views.
Figure 1 is a partially cut-away side perspective view of the therapy table exercise apparatus;
Figure 2 is a partially cut-away sectional view of the apparatus of Figure 1 taken along the arrows 2-2; and
Figure 3 is an electrical schematic diagram showing the brake and the electrical control circuitry used for controlling the brake in this invention.
[0014] Figure 1 shows a therapy table exercise apparatus 10 including a bench 12 which consists of a horizontal slab 14 mounted on a plurality of vertical legs 16. The bench 12 is of sufficient size and construction to support a supine human being 11. A holder bar 18, formed as a rectangular C-shaped bar, is rotatably mounted about an axis 13 on the bench 12. The holder bar 18 may be rotated with respect to the bench 12 to move counterclockwise in the direction shown by an arrow 20, by the user 11, or to move clockwise in the direction shown by an arrow 22.
[0015] A combined pivot bearing and brake 24 is securely attached to one side of the bench 12 at the axis 13 and is axially aligned with a bearing 26, which is attached to the opposite side of the bench 12 along the axis 13. The holder bar 18 is rotatably mounted on the brake 24 and the bearing 26, so that the holder bar 18 is retained relative to bench 12 but is rotatable about the axis 13 with respect to the bench 12, with the brake 24 providing resistance force to clockwise and counterclockwise movement of the holder bar 18.
[0016] A rotational transducer 28 is mounted between the holder bar 18 and the bench 12 to sense the angular orientation of holder bar 18 with respect to bench 12. The rotational transducer 28 also serves to produce an electrical orientation signal indicative of the angular orientation of the holder bar 18 with respect to the bench 12 and also of the end limits of travel.
[0017] The rotational transducer 28 is an electrical commutator switch assembly consisting, in part, of a plate 30 having plural electrically conductive sector pads 32, 34, 36, 42 and 44 mounted along a circular path. The pads 32, 34, and 36 serve to define angular ranges in the rotation of the holder bar 18 with respect to the bench 12. The plate 30 is securely attached to the brake 24 so that the plate 30 is fixed in place relative to the bench 12.
[0018] The rotational transducer 28 also includes a wiper 38 rotatably mounted on plate 30 so that wiper 38 passes over, and makes electrical contact with, each of the sector pads 32, 34, 36, 42 and 44 as holder bar 18 is rotated with respect to bench 12. The wiper 38 is securely mechanically attached to the holder bar 18 and is electrically connected to a control box 39 by means of an electrical cable 40. The cable 40 includes a plurality of electrically conductive wires for interconnecting the wiper 38 and the sector pads 32, 34, 36, 42 and 44 with the control box 39.
[0019] The pair of sector pads 42 and 44 are securely mechanically attached to the plate 30 and thus fixed relative to the bench 12. As the holder bar 18 is rotated to the end of its motion in a forward direction, as shown by the arrow 20, the wiper 38 contacts the sector pad 44. Similarly, the sector pad 42 is contacted by wiper 38 when the holder bar 18 is rotated to the end of its motion in a reverse direction, as shown by the arrow 22. Taken together, sector pads 42 and 44 cooperate to define an operating angular range in the rotation of the holder bar 18 with respect to the bench 12.
[0020] Although the preferred embodiment of Figure 1 discloses a rotational transducer 28 having five sector pads 32, 34, 36, 42 and 44, it should be understood that any number of sector pads greater than one would suffice to allow sensing of the angular orientation of the holder bar 18 with respect to the bench 12. The sector pads 32, 34, 36, 42 and 44 may be arranged in a circumferentially spaced-apart fashion as shown in Figure 1 or may be radially staggered so that wiper 38 is allowed to simultaneously contact adjacent sector pads. The precision or resolution of the sensing of angular orientation between the holder bar 18 and the bench 12 would be increased by increasing the number of sector pads mounted on plate 30.
[0021] The control box 39 houses a power supply circuit which produces an electrical output signal, and a force programming circuit electrically connected to the power supply circuit. The force programming circuit controls the transfer of electrical power from the power supply circuit to the brake 24 to thereby control the braking force exerted by the brake 24 on the holder bar 18. Plural control knobs 46, 48, and 50 are mounted on the control box 39 and are adjustable to independently control the magnitude of the braking force provided by the brake 24 at each of the three angular orientations defined by pads 32, 34, and 36 when the holder bar 18 is moved in a forward direction 20. Similarly, plural control knobs 52, 54, and 56 are mounted on the control box 39 and are adjustable to control the braking force as holder bar 18 is rotated in a reverse direction 22.
[0022] Referring next to Figure 2, the brake 24 includes a stator 58 attached to the bench 12 and having a stator coil 60 securely mounted therein. The stator coil 60 consists of a plurality of electrically conductive wire windings. The brake 24 is a commercially available electromechanical brake of the type manufactured by W. J. Industries, Inc., 10235 Bach Boulevard, St. Louis, Missouri 63132, U.S.A. The brake 24 also includes a rotor 62 and a pair of bearings 64 and 66 which support and align the rotor 62 in the stator 58. A shaft 68 extending from the holder bar 18 along the axis 13 is insertably mounted in and attached to the rotor 62. Thus, the bearings 64 and 66 rotatably support and align the holder bar 18 in stator 58 and further serve to retain the holder bar 18 relative to the bench 12.
[0023] Magnetic powder 70 is contained within the brake 24 between the coil 60 and the rotor 62. This magnetic powder 70 provides a bonding force between the coil 60 and the rotor 62, the magnitude of which is controlled by the magnitude of an electrical braking signal provided to the coil 60 from the control box 39. This magnetic powder 70 is a key element in the operation of the brake 24, in that the powder 70 functions as an electrically controllable, variable bond or link between the rotor 62 and the coil 60. The bonding force provided by the powder 70 is transferred through the coil 60, the stator 58, and the rotor 62 to produce a braking force that opposes rotation of the holder bar 18 relative to the table 12.
[0024] The electric braking signal provided by the control box 39 creates a current in the coil 60 which, in turn, creates a magnetic field (flux) which passes through the rotor 62, stator 58, and the magnetic powder 70. The magnetic field aligns the powder 70, forming links or bonds between the rotor 62 and the coil 60. The magnitude of bonding is approximately proportional to the magnitude of current in coil 60.
[0025] A wiper pad 72 is electrically conductive and is a portion of the wiper 38. Wiper pad 72 passes over, and makes electrical contact with, each of the sector pads 32, 34, and 36, in turn, as the holder bar 18 is rotated with respect to the bench 12. The wiper pad 72 is electrically connected with the control box 39.
[0026] Referring next to Figure 3, the control box 39 includes a power supply 76, a commercially available unit which serves to convert AC line power to a regulated DC voltage.
[0027] The DC control voltages of the power supply 76 are electrically connected to a double throw relay 78 of the usual, commercially available type. The relay 78 includes one pole for each of the number of sector pads mounted on the plate 30. As will be understood from the following description, the relay 78, in conjunction with the sector pads 42 and 44, provides a latching relay function. The unlatched state of the relay 78 corresponds to operation of the exercise apparatus 10 when the holder bar 18 is moving in a forward direction, as shown by arrow 20 (Figure 1). The latched state of relay 78 corresponds to the operation of exercise apparatus 10 when the holder bar 18 is moving in a reverse direction, as shown by arrow 22 (Figure 1).
[0028] The electrical contacts 42a and 44a are the electrical schematic representation of the sector pads 42 and 44, respectively, shown in Figure 1. The electrical contact 44a is normally open and momentarily closes to energize the coil 80, and thus close the relay contactor 79 to latch the relay 78, when the holder bar 18 contacts the electrical contact 44. The electrical contact 42a is normally open and is connected in parallel with the electrical contact 44a to provide current to the coil 80, and thus latch the relay 78, once the switch 44a has been momentarily closed. After assuming a latched state, the relay 78 assumes an unlatched state when the wiper 38 contacts the sector pad 42. Thus, the relay 78 provides a "memory" to indicate the direction that the holder bar 18 is being moved.
[0029] Plural variable resistors 52a, 54a, and 56a correspond to the control knobs 52, 54, and 56, respectively, of Figure 1. The wipers of these variable resistors 52a, 54a, and 56a are connected to a first terminal 81 of the relay 78 to energize the power supply 76 only when the relay 78 is in its unlatched state. Thus, the variable resistors 52a, 54a, and 56a serve to control the magnitude of current provided to the brake 24a when the holder bar 18 is moving in a reverse direction, as shown by arrow 22 (Figure 1). The brake 24a is an electrical schematic representation corresponding to the brake 24 of Figure 1.
[0030] An additional group of variable resistors 46a, 48a, and 50a correspond to control knobs 46, 48, and 50 of Figure 1. The wipers of these resistors 46a, 48a, and 50a are connected to a second terminal 83 of the relay 78 to energize the power supply 76 only when the relay 78 is in its latched state. The variable resistors 46a, 48a, and 50a serve to control the magnitude of current provided to the brake 24a when the holder bar 18 is moved in a forward direction, as shown by arrow 20 (Figure 1).
[0031] The variable resistors 46a-56a may each be independently adjusted to control the magnitude of current provided to the brake 24a as the wiper 38 (Figure 2) moves across sector pads 32, 34, and 36, respectively. Electrical contacts 32a, 34a, and 36a are schematic representations of the sector pads 32, 34, and 36 (Figure 1), respectively, while a switch arm 72a is an electrical schematic representation of the wiper 38. The function of switch arm 72a is to make selective electrical contact with one of the electrical contacts 32a, 34a, or 36a as the holder bar 18 is moved through sequential rotational segments. When the switch arm 72a connects with the contact 32a, power for the brake 24a is controlled by the variable resistor 46a or 52a, depending upon the state of relay 78. Similarly, when the switch arm 72a connects with contact 34a, the current in the brake 24a is controlled by the variable resistor 48a or 54a, depending upon the state of relay 78. Also, when switch arm 72a connects with contact 36a, the variable resistor 50a or 56a controls the current provided to brake 24a, depending upon the state of relay 78.
[0032] The elements disclosed in Figure 3, absent the brake 24a, form an electrical control circuit to supply an electric braking signal to the brake 24a, and to thereby control the braking force provided by the brake 24. The arm 72a, when combined with the contacts 32a, 34a, and 36a, corresponds to a rotational transducer which produces an electrical orientation signal indicative of the angular orientation of the holder bar 18 with respect to the bench 12. Taken together, the variable resistors 46a-56a form a force programming circuitry to control the transfer of electrical power from the power supply 76 to the brake 24a and to thereby control the braking force provided by the brake 24. Taken together, the relay 78, the electrical contact 42a, and the electrical contact 44a form a direction sensing and control circuitto sense the direction of rotation of the holder bar 18 with respect to the bench 12 and to control the force programming circuitry to independently select the magnitude of braking force for each direction of rotation of the holder bar 18.
[0033] The electrical resistance of each of the variable resistors 46a-56a are independently adjustable to control the transfer of electrical power to the brake 24a. These variable resistors 46a-56a cooperate with the sector pads 32, 34, and 36 to define independently adjustable resistance force ranges corresponding to angular ranges in the rotation of the holder bar 18.
[0034] Thus, when holder bar 18 is rotated so that the wiper 38 contacts the sector pad 32, and the holder bar 18 is moving in a forward direction so that the relay 78 is in an unlatched state, the magnitude of braking provided by the brake 24 is controlled by the setting of variable resistor 46a. Under the same conditions, as bar 18 is rotated so that the wiper 38 moves onto pad 34, the setting of the variable resistor 48a controls the braking force provided by the brake 24. Then, under the same conditions, as the wiper 38 moves onto the pad 36, the magnitude of braking force is controlled by the setting of the variable resistor 50a. When the holder bar 18 moves fully forward to touch limit switch 44, thus causing the relay 78 to latch, the variable resistor 56a will control the magnitude of current provided to brake 24a as holder bar 18 is moved in a reverse direction, as shown by the arrow 22. As the holder bar 18 is pulled further backwards, the wiper 38 moves into contact with the pad 34 so that the variable resistor 54a controls the magnitude of braking force. Under the same conditions, as the holder bar 18 is rotated so that the wiper 38 contacts the sector pad 32, the variable resistor 52a controls the magnitude of braking force provided by the brake 24. Finally, the holder bar 18 is moved fully back in a reverse direction, the holder bar 18 contacts the sector pad 42 which causes the relay 78 to unlatch, thus allowing the cycle to be repeated.
[0035] The sector pads 32-36 are formed to cover rotational segments of the bar 18 in accordance with physical therapy requirements, and may thus extend through unequal angular ranges.
[0036] In operation, a person using this exercise apparatus 10 may lie down in a horizontal position on the slab 14. The user's upper torso is preferably placed across the axis 13 so that the user's arms may conveniently be extended to allow the userto grasp the holder bar 18. The holder bar 18 is then rotated by the user who may exert pushing and pulling forces using his or her arm, shoulder, and back muscles. The rotational transducer 28 defines a plurality of angular ranges in the rotation of the holder bar 18 so that braking forces applied to the bar 18 may be adjusted according to the angular orientation of the bar 18. As the bar 18 is rotated, various different groups of the user's muscles come into play and the groups of muscles vary in their relative strength. Thus, the rotational transducer 28 allows the exercise apparatus 10 to be adjusted so that each of the groups of the user's muscles is stressed to the desired degree. This adjustment is performed by varying the settings of the knobs 4656.
[0037] When in such a horizontal, supine position, the user imitates a rowing motion with his hands to cause the holder bar 18 to oscillate between the sector pad 42 and the sector pad 44. The relay 78 is provided to allow a different level of stress to be applied to muscles which are used to push the bar 18 in the direction 20 than the stress which is provided to muscles which are used to pull the bar 18 in the direction 22.
[0038] The exercise apparatus 10 may be modified by changing the shape of holder bar 18 to allow a user to sit upon the slab 14 and to move the bar 18 with the user's feet and legs. A further possible variation for the exercise apparatus 10 is to change the shape of holder bar 18 so that a user may stand vertically adjacent the bench 14 and move the bar 18 up and down with the aid of the user's hands and arms.
an electrical commutator switch assembly attached to the base (12), including a plate (30) having a plurality of electrically conductive sector pads (32, 34, 36) mounted along a path thereon, the sector pads defining ranges in the movement of the member (18) with respect to the base;
a wiper (38) mounted on the member (18) and having sequential electrical contact with
each of the sector pads (32, 34, 36) as the member (18) is moved relative to the base
(12);
first and second sets of electrical resistors, each set including a plurality of electrical
resistors (46a, 48a, 50a, 52a, 54a, 56a) having variable resistance, wherein one resistor
of each set is selectively connected to one of the sector pads (32, 34, 36), and wherein
the resistance of each of the variable resistors (46a, 48a, 50a, 52a, 54a, 56a) is
independently adjustable;
a first end electrical contact (42) mounted on the base (12) so as to be contacted by the wiper (38) when the member (18) is at the end of its movement in the reverse direction (22), and a second end electrical contact (44) mounted on the base (12) so as to be contacted by the wiper (38) when the member (18) is at the end of its movement in the forward direction (20), wherein when the wiper contacts the first end electrical contact (42) the resistors (46a, 48a, 50a) of the first set of resistors are connected to the sector pads (32, 34, 36), and when the wiper (38) contacts the second end electrical contact (44) the resistors (52a, 54a, 56a) of the second set of resistors are connected to the sector pads (32, 34, 36) so that when the member (18) is rotated in the forward direction to move the wiper (38) from the first end contact (42) to the second end contact (44), the first set of resistors (46a, 48a, 50a) is connected to the sector pads (32, 34, 36), and as the member (18) is rotated in the reverse direction to move the wiper (38) from the second end contact (44) to the first end contact (42) the second set of resistors (52a, 54a, 56a) is connected to the sector pads; and
a power supply (76) connected to the magnetic brake (24), to the wiper (38), and to the variable resistors (46a, 48a, 50a, 52a, 54a, 56a) so that when the wiper contacts one of the sector pads (32, 34, 36) a circuit is formed to supply a current to the magnetic brake, wherein the magnitude of the current is controlled by the variable resistance of the resistor connected to the contacted sector pad.
a plurality of poles, each pole connected to one of the sector pads (32, 34, 36);
a plurality of first terminals (81), each connected to one of the variable resistors of the second set of variable resistors (52a, 54a, 56a);
a plurality of second terminals (83), each connected to one of the variable resistors of the first set of variable resistors (46a, 58a, 50a); and
a plurality of relay contactors (79), each connected between one of the poles and, alternatively, one of the first terminals (81) or one of the second terminals (83);
wherein when the wiper (38) contacts the second end contact (44) the relay contactors (79) connect the poles and the first terminals (81) to connect the second set of resistors (52a, 54a, 56a) to the sector pads (32, 34, 36); and
wherein when the wiper contacts the first end contact (42) the relay contactors (79) connect the poles and the second terminals (83) to connect the first set of resistors (46a, 48a, 50a) to the sector pads (32, 34, 36).
- eine an dem Gestell (12) angeordnete elektrische Umschaltanordnung, die eine Platte (30) aufweist, die eine Vielzahl von elektrisch leitfähigen Sektor-Anschlußgliedern (32, 34, 36) trägt, die längs einer Bahn darauf angeordnet sind, wobei die Sektor-Anschlußglieder Bewegungsbereiche des Glieds (18) in Bezug auf das Gestell definieren;
- ein an dem Glied (18) angeordneter Schleifarm (38), der nacheinander in elektrischen Kontakt mit jedem der Sektor-Anschlußglieder (32, 34,36) kommt, wenn das Glied (18) relativ zu dem Gestell (12) bewegt wird;
- erste und zweite Sätze von elektrischen Widerständen, von denen jeder Satz eine Vielzahl elektrischer Widerstände (46a, 48a, 50a, 52a, 54a, 56a) aufweist, die veränderlichen Widerstandswert haben, wobei ein Widerstand jedes Satzes wahlweise mit einem der Sektor-Anschlußglieder (32, 34, 36) verbunden ist, und wobei der Widerstandswert jedes der veränderlichen Widerstände (46a, 48a, 50a, 52a, 54a, 56a) unabhängig einstellbar ist;
- ein erster elektrischer Endkontakt (42), der an dem Gestell (12) so angeordnet ist, daß er durch den Schleifarm (38) berührt wird, wenn das Glied (18) am Ende seiner Bewegung in der Rückwärtsrichtung (22) ist, und ein zweiter elektrischer Endkontakt (44), der an dem Gestell (12) so angeordnet ist, daß er von dem Schleifarm (38) berührt wird, wenn das Glied (18) an dem Ende seiner Bewegung in der Vorwärtsrichtung (20) ist, wobei bei Berührung des Schleifarms mit dem ersten elektrischen Endkontakt (42) die Widerstände (46a, 48a, 50a) des ersten Satzes von Widerständen mit den Sektor-Anschlußgliedern (32, 34, 36) verbunden sind und bei Berührung des Schleifarms (38) mit dem zweiten elektrischen Endkontakt (44) die Widerstände (52a, 54a, 56a) des zweiten Satzes von Widerständen mit den Sektor-Anschlußgliedern (32, 34, 36) verbunden sind, so daß, wenn das Glied (18) in der Vorwärtsrichtung gedreht wird, um den Schleifarm (38) von dem ersten Endkontakt (42) zu dem zweiten Endkontakt (44) zu bewegen, der erste Satz von Widerständen (46a, 48a, 50a) mit den Sektor-Anschlußgliedern (32, 34, 36) verbunden ist, und wenn das Glied (18) in der Rückwärtsrichtung gedreht wird, um den Schleifarm (38) von dem zweiten Endkontakt (44) zu dem ersten Endkontakt (42) zu bewegen, der zweite Satz von Widerständen (52a, 54a, 56a) mit den Sektor-Anschlußgliedern verbunden ist; und
-eine Energieversorgung (76), die mit der magnetischen Bremse (24), mit dem Schleifarm (38) und mit den variablen Widerständen (46a, 48a, 50a, 52a, 54a, 56a) verbunden ist, so daß bei Kontakt des Schleifarms mit einem der Sektor-Anschlußglieder (32, 34, 36) ein Stromkreis gebildet ist, um der magnetischen Bremse Strom zuzuführen, wobei die Größe des Stroms gesteuert ist durch den veränderlichen Widerstandswert des Widerstands, der mit dem berührten Sektor-Anschlußglied verbunden ist.
- eine Vielzahl von Polen, von denen jeder Pol mit einem der Sektor-Anschlußglieder (32, 34, 36) verbunden ist;
- eine Vielzahl von ersten Anschlüssen (81), von denen jeder mit einem der veränderlichen Widerstände des zweiten Satzes veränderlicher Widerstände (53a, 54a, 55a) verbunden ist;
- eine Vielzahl zweiter Anschlüsse (83), von denen jeder mit einem der veränderlichen Widerstände des ersten Satzes veränderlicher Widerstände (16a, 48a, 50a) verbunden ist; und
- eine Vielzahl von Relais-Kontaktgliedern (79), von denen jedes zwischen einem der Pole und, alternativ, einem der ersten Anschlüsse (81) oder einem der zweiten Anschlüsse (83) verbunden ist;
- wobei bei Berührung des Schleifarms (38) mit dem zweiten Endkontakt (44) die Relais-Kontaktglieder (79) die Pole und die ersten Anschlüsse (81) verbinden, um den zweiten Satz von Widerständen (52a, 54a, 56a) mit den Sektor-Anschlußgliedern (32, 34, 36) zu verbinden; und
-wobei bei Berührung des Schleifarms mit dem ersten Endkontakt (42) die Relais-Kontaktglieder (79) die Pole und die zweiten Anschlüsse (83) verbinden, um den ersten Satz von Widerständen (46a, 48a, 50a) mit den Sektor-Anschlußgliedern (32, 34, 36) zu verbinden.
un ensemble de commutation à collecteur électrique fixé à la base (12), comprenant une plaque (30) portant plusieurs plots sectoraux électriquement conducteurs (32, 34, 36) montés le long d'un trajet, les plots sectoraux définissant des plages angulaires du mouvement de l'élément (18) par rapport à la base;
un curseur (38) monté sur l'élément (18) et établissant un contact électrique séquentiel avec chacun des plots sectoraux (32, 34, 36) lorsque l'élément (18) est déplacé par rapport à la base (12);
des premier et second jeux de résistances électriques, chaque jeu comprenant plusieurs résistances électriques (46a, 48a, 50a, 52a, 54a, 56a) de valeur variable, une résistance de chaque jeu étant connectée sélectivement à l'un des plots sectoraux (32, 34, 36), et la valeur de chacune des résistances variables (46a, 48a, 50a, 52a, 54a, 56a) étant réglable de façon indépendante;
un premier contact électrique d'extrémité (42) monté sur la base (12) de façon que le curseur (38) porte contre lui lorsque l'élément (18) se trouve au bout de son mouvement dans le sens arrière (22), et un second contact électrique d'extrémité (44) monté sur la base (12) afin que le curseur (38) porte contre lui lorsque l'élément (18) se trouve au bout de son mouvement dans le sens avant (20), de manière que, lorsque le curseur porte contre le premier contact électrique d'extrémité (42), les résistances (46a, 48a, 50a) du premier jeu de résistances soient connectées aux plots sectoraux (32, 34, 36) et que, lorsque le curseur (38) porte contre le second contact électrique d'extrémité (44), les résistances (52a, 54a, 56a) du second jeu de résistances soient connectées aux plots sectoraux (32, 34, 36) afin que, lorsque l'élément (18) est tourné dans le sens avant pour déplacer le curseur (38) du premier contact d'extrémité (42) vers le second contact d'extrémité (44), le premier jeu de résistances (46a, 48a, 50a) soit connecté aux plots sectoraux (32, 34 et 36) et, lorsque l'élément (18) est tourné dans le sens arrière pour déplacer le curseur (38) du second contact d'extrémité (44) vers le premier contact d'extrémité (42), le second jeu de résistances (52a, 54a, 56a) soit connecté aux plots sectoraux; et
une alimentation en énergie (76) connectée au frein magnétique (24), au curseur (38) et aux résistances variables (46a, 48a, 50a, 52a, 54a, 56a) afin que, lorsque le curseur porte contre un des plots sectoraux (32, 34, 36), un circuit soit formé pour fournir un courant au frein magnétique, l'amplitude du courant étant déterminée par la valeur variable de la résistance connectée au plot sectoral contre lequel porte le curseur.
plusieurs pôles, chaque pôle étant connecté à l'un des plots sectoraux (32, 34, 36);
plusieurs premières bornes (81) connectées chacune à l'une des résistances variables du second jeu de résistances variables (52a, 54a, 56a);
plusieurs secondes bornes (83) connectées chacune à l'une des résistances variables du premier jeu de résistances variables (46a, 58a, 50a); et plusieurs lames (79) de relais connectées chacune entre l'un des pôles et, alternativement, l'une des premières bornes (81) ou l'une des secondes bornes (83);
dans lequel, lorsque le curseur (38) porte contre le second contact d'extrémité (44), les lames (79) du relais connectent les pôles et les premières bornes (81) afin de connecter le second jeu de résistances (52a, 54a, 56a) aux plots sectoraux (32, 34, 36); et
dans lequel, lorsque le curseur porte contre le premier contact d'extrémité (42), les lames (79) du relais connectent les pôles et les secondes bornes (83) afin de connecter le premier jeu de résistances (46a, 48a, 50a) aux plots sectoraux (32, 34, 36).