Before the game, the Flyers agreed to a long-term contract extension with center Jeff Carter, a deal reported to be for 11 years and $58 million. Carter joined teammates Richards, Giroux, Danny Briere and Chris Pronger, who have signed long deals with the Flyers.
After scoring one goal in his first 12 games this season, Richards has five in five games.
"I see his confidence building," Flyers coach Peter Laviolette said. "He was flying out there. He was a noticeable player. He had a lot of speed in his game, a lot of attack to his game. I thought his line was good. I think he's been getting stronger as we go."
Richards sparked Philadelphia's offense at 12:14 in the first period. Taking a feed from Andreas Nodl, Richards split two defenders and fired a shot past goalie Scott Clemmensen's stick side.
Richards hadn't scored in 19 career games against Florida, which had been the only Eastern Conference team to hold him without a goal.
"He sure made up for it," Panthers coach Pete DeBoer said. "We hung with them for the first 12 minutes, but when you make mistakes against a great hockey team, the hottest team in the league, they make you pay."
Hartnell gave the Flyers a 2-0 lead at 15:38, tipping a cross-ice pass from Ville Leino into a corner of the net. Leino had two assists, giving him 11 points in 12 games.
The Flyers peppered Clemmensen in the second period. Richards began that surge, too, scoring 15 seconds into a Philadelphia power play. His one-timer from inside the circle went in after defecting off the left crossbar.
Giroux reclaimed the team lead with his eighth and ninth goals, completing the Flyers' season-high, 42-shot attack. The 22-year-old forward, who last week signed a three-year, $11.25 million contract, punched in his first of the night at 8:33 of the second. He tipped in his own rebound amid a scramble in front.
Giroux needed no help on his second goal, when he blocked a shot from Bryan Allen, recovered the loose puck, then beat Clemmensen to the glove side with a forehand-to-backhand deke.
"I just read the goalie and tried to think about what I was going to do," Giroux said. "The puck was jumping, so I just tried to get a shot off. It worked."
Clemmensen made 37 saves.
The 22-year-old Bobrovsky, who has quickly won over fans with his sterling play, was also credited with his first NHL assist on Richards' first goal.
Stillman scored first for the Panthers, deflecting Keaton Ellerby's shot with a his stick, and the puck soared over Bobrovsky's shoulder. Santorelli completed the scoring, placing a wrist shot past Bobrovsky in the closing minutes.
Nodl took a shot to his big toe in the first period. He played briefly in the second period, then left the game. X-rays were negative. ... Florida won three of four from the Flyers last season. ... Richards needs one point to reach 300 for his career. ... Florida forward Steve Bernier, injured when he took a stick to the face at the end of Friday's game against Minnesota, didn't play on Saturday.