Coupled timepiece oscillators

An isochronous timepiece oscillator mechanism with coupled oscillators, consisting only of a first oscillator including a first elastic return attached to a fixed structure at a first anchoring point and to a first mobile component pivoting about a first axis, and a second oscillator including a second elastic return fixed to a second mobile component, wherein said first oscillator and said second oscillator are coupled to each other by mechanical connection via said second elastic return which is then attached to said first mobile component, wherein said first oscillator is a first sprung balance oscillator and wherein said first elastic return is a first balance spring attached to said fixed structure by a first balance spring stud forming said first anchoring point, and wherein said second oscillator is a second sprung balance oscillator and wherein said second elastic return is a second balance spring attached to said second mobile component, wherein said second balance spring is attached to the felloe or to an arm of said first mobile component at a second balance spring stud and to said second mobile component which pivots about a second axis, wherein maintenance of the oscillations of said oscillator mechanism is effected on only one of said first mobile component or second mobile component.