The circuit should work OK.
But: Remember one of the most basic engineering principles - KISS - Keep It Simple, Stupid!
How is that circuit in any way more functional or more advantageous than using the switch to directly control the relay coil - or indeed, control the lamp circuit directly?
As an educational project it is a novel application, but I do not see it to be more than that?
The circuit converts an SPDT pushbutton switch to alternate-action. U1A is a set-reset flipflop to debounce the switch, and U1B is a toggle flipflop that drives the output stage.I've still no idea what it does as you've never told us. And, I'm not willing to work it out.
The circuit converts an SPDT pushbutton switch to alternate-action. U1A is a set-reset flipflop to debounce the switch, and U1B is a toggle flipflop that drives the output stage.
There is a problem with all of the Set and Reset inputs. This would be more apparent if you drew a schematic instead of a wiring diagram. A correct schematic has separate symbols for each flipflop with the inputs and outputs arranged in a traditional manner, not the physical package. This makes its possible for any experienced viewer to see the intent of the design. Redraw the schematic and you will see the problem. Yes, the circuit works, but not by design.
See figure 3 of this datasheet for the correct schematic symbols.
ps. Ground symbols never point any direction but down. Antennae and power symbols point up; grounds point downward, always.
Unless you've already got +5V elsewhere in the system, I'd suggest changing the 74hc74 to a CD4013B flip-flop. The CD4000 series can run on 12 volts, so you wouldn't need a separate 5 Volt regulator. Be aware though, that the logic state of the S and R inputs are different between the hc74 and the 4013. Also the pinouts are different.
Also, I would eliminate the relay by using a mosfet to drive the LEDs.