The woman, who is in her sixties, was accused of trapping three young boys in a dryer after they had been playing in it.
On another occasion, she locked one of the three in the school's safe, the local Borås Tidningen (BT) newspaper reported.
She had also allegedly covered the mouth of a crying one-year-old girl and hit another child on the head before pulling the youngster's hair.
All of the children involved were between one and three at the time of the incidents.
While the teacher continued to maintain her innocence, the District Court in Borås on Wednesday nevertheless found her guilty of child abuse.
She was handed a suspended sentence and fine 6,000 kronor ($880).
The woman was also ordered to pay 10,000 kronor in damages to each of the families of the three children she locked in the dryer and 7,000 kronor to the family of another child.
The teacher's hard-handed tactics were eventually reported to school administrators by concerned colleagues last spring.
In January, prosecutors finally filed charges over assaults.
“My opinion is that this way of reprimanding children goes beyond the limits of what is permissible and acceptable", chief prosecutor Daniel Edsbagge told BT at the time.
Despite the guilty verdict, the woman denied having committed any crime, alleging that she had been the victim of a conspiracy hatched by her colleagues in a bid to have her fired.
But the court found that the account provided by other employees at the preschool was credible and that there was "no reason" they would have accused the woman of something she hadn't done, according to the Expressen newspaper.