Ace Tone (Ace Electronic Industries Inc) used to be a manufacturer of musical instruments, such as electronic organs, drum machines, effects pedals and synthesizers. Ace Tone was founded by Ikutaro Kakehashi in 1960. Ace Tone is considered an early version of Roland, which Kakehashi also founded. Ace Tone began its production of amplifiers, drum machines, electronic organs and synthesizers in 1963 (info from ihavesynth.com).
Rhythm Ace FR-3 is one of the first drum machines that could play preprogrammed rhythms which were created by electronics. Older machines like the Wurlitzer Sideman used mechanical devices to create the rhythms. The Rhythm Ace FR-3 could create rhythms with a diode matrix which was invented by Ikutaro Kakehashi and his team. The FR-3 was designed as a portable device. It was produced around the year 1973. It is a purely analog device. The instruments are based on LC circuits.
Rough English translation (front page):
Fully automated rhythm device – model FR-3
Rhythm-Ace FR-3 – the „electronic drummer“ which enables a perfect rhythmic accompaniment with completely natural reproduction.
Rhythm-Ace FR-3 – a musical novelty and an excellent aid for soloists and small orchestras. This device enables an enlarged repertoire and renders your play more effective. Your audience and not least yourself will be thrilled by this electronic rhythm device.
Rhythm-Ace FR-3 is in principle built like an electronic brain. It is programmed with 16 different rhythms. Furthermore you can create numerous new and interesting rhythmic patterns by mixing the various rhythms and percussive effects.
There is a second page with the technical details.