Re-adhesion apparatus for vehicles

Claim 2

The re-adhesion apparatus for a vehicle having at least one drive axle normally adhesively coupled with a drive surface and at least one other axle for coupling said vehicle with said drive surface, comprising: first means, coupled to said axles, for detecting the velocity between said drive surface and at least one of said axles, which has become nonadhesively coupled with said drive surface and providing a first signal representative of said velocity; second means, coupled with said drive surface, for detecting the speed of said vehicle and providing a second signal representative of said speed; third means responsive to said first and second means, for generating a third signal representative of the difference between said first and second signal; fourth means, responsive to said third means, for producing a fourth signal representative of the time derivative of said third signal; fifth means, responsive to said third and fourth means, for generating a fifth signal representative of the sum of said third and fourth signals; and sixth means, responsive to said fifth means, for generating an output when said fifth signal exceeds a predetermined level.

Claim 3

An apparatus in accordance with claim 1, wherein said second means includes said at least one other axle which is adhesively coupled with said drive surface.

Claim 4

An apparatus in accordance with claim 1, wherein said fourth means includes means for generating a modified fourth signal proportional to the absolute value of said fourth signal and wherein said fifth means is responsive to said modified fourth absolute value signal.

Claim 5

An apparatus in accordance with claim 1, wherein said vehicle has a pair of axles and wherein said second means is responsive to the velocities of said pair of axles for providing a respective pair of signals inverted with respect to each other and indicative of the velocities of said axles and further including a first relay, responsive to said means for generating said pairs of signals, for providiNg said second signal when said pair of signals reach a preset level.

Claim 6

An apparatus in accordance with claim 1, wherein said vehicle has a pair of axles and wherein said fourth means is responsive to the velocities of said pair of axles for providing a respective pair of differential signals inverted with respect to each other and indicative of the velocities of said axles and further including a second relay, responsive to said means for generating said pairs of signals, for providing said fourth signal when said pair of signals reach a preset level.

Claim 7

An apparatus in accordance with claim 1, wherein said vehicle has a pair of additional axles, and wherein said third means includes means for detecting the difference between the velocities of said pair of additional axles and for generating a signal indicative thereof, and further including a third relay, responsive to said additional axle velocity difference signal, for providing said third signal, when said difference signal reaches a preset level.

Claim 8

An apparatus in accordance with claim 6, wherein said third means further includes a bridge circuit for receiving pairs of signals from said additional axles for balancing said signals thereacross to provide said difference signal.

Claim 9

An apparatus in accordance with claim 1, wherein said vehicle has a pair of additional axles, and wherein said fourth means includes means for detecting the difference between the velocities of said pairs of additional axles and for generating a signal indicative thereof, and further including a fourth relay, responsive to said additional axle velocity difference signal, for providing said fourth signal when said difference signal reaches a preset level.

Claim 10

An apparatus in accordance with claim 1, wherein said sixth means includes a relay circuit responsive to a predetermined level of said fifth signal for generating said output.

Claim 11

An apparatus in accordance with claim 1, wherein said vehicle further includes a plurality of axles, which are normally adhesively coupled with said drive surface, and wherein said first means includes means for detecting the velocities between said drive surface and at least two of said axles, which have become nonadhesively coupled with said drive surface to provide a first set of signals representative of said velocities.

Claim 12

An apparatus in accordance with claim 10, wherein said third means includes means for providing a deviation signal representative of the greatest difference between said second signal and a signal produced by said first means to provide said third signal.

Claim 13

An apparatus in accordance with claim 1, wherein said vehicle further includes an electric motor coupled with at least the one of said axles which has become nonadhesively coupled with said drive surface for applying a mechanical force to said axle, and further includes seventh means, responsive to the output of said sixth means, for decreasing the mechanical force applied to said axle.

Claim 14

An apparatus in accordance with claim 12, wherein each of said axles includes an electric motor coupled therewith, each motor having an armature portion, and wherein said first and second means include means for generating said first and second signals in response to the magnitude of the respective armature voltages.

Claim 15

An apparatus in accordance with claim 13, wherein said seventh means includes means for retarding the buildup of the armature voltages across the motor coupled to said nonadhesively coupled axle.

Claim 16

An apparatus in accordance with claim 13, wherein each of said motors includes a field winding, and wherein said seventh means includes means for reducing the field current flowing through the motor coupled to said nonadhesively coupled axle.

Claim 17

An apparatus in accordance with claim 1, wherein said vehicle further includes an air brake coupled with at least the one of said axles which has become nonadhesively coupled with said drive surface for applying a braking force to said axle and further includes brAke means, responsive to the output of said sixth means, for imparting a braking force to said axle.

Claim 18

An apparatus in accordance with claim 16, wherein said airbrake includes a brake cylinder and a source of compressed air therefore, including an auxiliary air tank communicating with said cylinder through an air supplying surface, for supplying brake imparting air pressure to said brake in response to said output signal.

Claim 19

An apparatus in accordance with claim 16, wherein said brake means includes means for detecting the output of said sixth means, for decreasing the amount of braking force applied to said axle, so as to reduce and stop nonadhesive skidding.

Claim 20

An apparatus in accordance with claim 18, further including a brake cylinder and an adjusting valve, associated with said airbrake, and responsive to said sixth means, for exhausting compressed air from said brake cylinder, and wherein said sixth means includes means, coupled with said adjusting valve, for varying the operation thereof in response to said output signal.

Claim 21

A re-adhesion apparatus according to claim 9, wherein said vehicle further includes a pair of sets of electric motors, each including an armature and a field winding, for driving the vehicle axles, the armatures of each of said motors being connected to said third means, each including a pair of magnetic amplifiers, each of which having a pair of windings, therein, the polarities of the windings of each magnetic amplifier in said third means associated with each motor being of a polarity opposite the polarity of the windings in the other magnetic amplifier in each of said third means.

Claim 22

A re-adhesion apparatus according to claim 20, further including a capacitor and a full-wave rectifier connected in series with one of the windings of each magnetic amplifier in said pair of magnetic amplifiers to provide a signal representative of the absolute value of the differential of the slip velocity, said capacitor and full-wave rectifier being connected in parallel with the other of the windings of each of said magnetic amplifiers in said pair of magnetic amplifiers, so as to deliver to each respective armature a signal representative of said fifth signal.

Claim 23

A re-adhesion apparatus according to claim 21, wherein each magnetic amplifier is is provided with a pair of bias windings connected to an adjustable power source for individually varying the characteristics and detection sensitivity thereof, and further including feedback windings to impart positive feedback thereto so as to provide said magnetic amplifiers with the desired switching characteristics of a relay, and further including a pair of output windings associated with each magnetic amplifier, wherein the outputs of said output windings are connected through respective rectifiers to a pair of slip relays for controlling said vehicle system.

Claim 24

A re-adhesion system according to claim 22, further including a pair of thyristors connected to said slip relays and the power source for said magnetic amplifiers, the control electrodes of said thyristors being activated by the outputs of said respective rectifiers.

Claim 25

A re-adhesion system according to claim 9, wherein said vehicle further comprises a pair of sets of electric motors, each including an armatuRe and a field winding for driving the vehicle axles, the armatures of each of said motors being connected to said third means, each including a magnetic amplifier having a pair of windings therein, and being provided with a pair of bias windings connected to an adjustable power source for individually varying the characteristics and detection sensitivity thereof and further having a feedback winding connected magnetically in parallel therewith to impart positive feedback thereto, so as to provide said magnetic amplifier with desired switching characteristics and also having a pair of output windings, connected magnetically in parallel with said feedback winding, and wherein each magnetic amplifier includes a pair of control winding sets, one of the windings in each set being connected in series with a capacitor and a full-wave rectifier to provide a signal representative of said fourth signal indicative of the absolute value of the differential of the slip velocity associated with said set, said capacitor and said full-wave rectifier being connected in parallel with the other winding of said set, so as to deliver to each respective armature a signal representative of said fifth signal.

Claim 26

A re-adhesion apparatus according to claim 9 wherein said vehicle comprises a pair of sets of electric motors, each including an armature and a field winding, for driving the vehicle axles, the armatures of each of said motors being connected to said third means, each including a pair of magnetic amplifiers, and wherein pairs of armatures form adjacent arms of a bridge circuit, the other adjacent arms of the bridge circuit being formed by a pair of resistances, the connection points between the elements of adjacent arms being connected to a reversing switch for connecting said third means according to the polarity desired across said bridge, depending upon whether said vehicle is being powered or braked.