Michael Ward and Marie Pritchard snatched their taxi fare back from the driver before stealing his keys and mobile during the robbery.
The pair, aged 31, targeted the ‘shaken-up’ driver whilst on bail for a string of offences.
Sentencing at Wolverhampton Crown Court, Judge Amjad Nawaz said: “Taxi drivers are vulnerable in a sense because they don’t know who is going to get in their car. They are easy prey.”
The defendants were picked up in Coseley’s Castle Street, heading for Dudley, before disagreeing about paying with a £20 or two £10 notes at about 1.45am.
Ward got out of the taxi, opened the passenger door and tried to grab the cash after handing it over in St James’s Road.
He then struck the driver to his head before stealing the fare and the victim’s phone on April 6 last year.
Ward fled, followed by Pritchard, who gave birth to her and Ward’s son while in custody, after she grabbed the keys from the ignition.
It came after an incident which saw the pair visiting the Tividale home of Joe Edwards’ parents, a man Ward had ‘problems’ with.
Ward kicked the front door, with Pritchard pushing her way into the house during the early hours of January 15 last year.
Pritchard, who was ‘very drunk’, brandished a wine bottle and tried to smash a light, while ‘agitated’ Ward held a blade.
Ward was heard saying: “I’m going to stab him, I’m going to cut him up. I’m going to shoot him. I’m going to get my granddad’s shotgun.”
More than £7,000 of damage was then caused outside as Ward smashed a car windscreen, and slashed a wing mirror and tyre.
Armed with a metal bar, he then drove to the home of his mother’s friend, smashing her car windscreen, house windows and front door.
Defence barrister Mr Sunit Sandhu said Ward wanted to apologise to his victims, adding: “None of these threats would have been carried out.
"The defendant had no access to any firearms. This was a drunken haze.”
Ms Samantha Forsythe, defending Pritchard, said she has realised she ‘has to change’.
Ward, of Tower Street, Dudley, was jailed for 52 months while Pritchard, of no fixed abode, was jailed for 48 months.
Both admitted robbery and affray.
Ward also admitted making a threat to kill, possession of a bladed article and criminal damage, while Pritchard admitted being in breach of previous court orders.
A petition calling for Erewash cabbies to be allowed to have fully-tinted windows in their taxis has been rejected over fears that vehicles could be used to enable the abuse of vulnerable children and adults.