CEDAR RAPIDS, Iowa (AP) _ A federal magistrate's ruling Tuesday cleared the way for just one of Bill Haley's Comets to rock around the clock.

U.S. Magistrate John Jarvey approved a preliminary injunction request by John ''BamBam'' Lane Barrowclough of Crum Lynne, Pa., a drummer who joined Haley's band in 1965, to stop a New Jersey man from performing under the name Bill Haley's Comets or any similar name.

Haley, one of rock 'n' roll's pioneers known for such hits as ''Rock Around the Clock'' and ''See Ya Later Alligator,'' died in February 1981, nearly 30 years after forming the band Bill Haley & The Comets.

Barrowclough, one of five musicians who comprise the group Bill Haley's Comets, contended that a group headed by Joseph Grazino of Pemberton, N.J., was causing confusion by using Haley's name and was costing Barrowclough's band jobs.

The complaint was filed after a June 3 performance in Mason City by Grazino's band, which also bills itself as Bill Haley's Comets.

Barrowclough and two partners - band member Al Rappa and the Jolly Joyce Agency booking agency - have held trademark rights to the names Haley's Comets and Bill Haley's Comets since Oct. 21, 1987. The group claimed trademark infringement, unfair competition and false designation under the federal trademark act.

Grazino, who does business as Joey Rand and was referred to as Rand throughout the injunction hearing, did not attend the session nor was he represented by anyone. There is no telephone listing for Grazino in Pemberton, N.J., and efforts to reach him were unsuccessful.

Barrowclough said he was happy with the ruling and hopes it will clear up confusion among booking agents and fans.

''The market for Bill Haley's Comets is worldwide,'' he said. ''When people come to see Bill Haley's Comets, they don't know there are, or used to be, two Bill Haley's Comets.''

Grazino received permission from Jolly Joyce to use the Haley name for his performances from Dec. 8, 1981, to Dec. 8, 1984. Barrowclough said that was during a time when he and the agency were fighting each other on the trademark issue and that Joyce had no authority to grant permission. The differences have been reconciled and Joyce no longer books acts for Grazino.

''Rand has never worked with Bill Haley, although he states he has. He never appeared with Bill Haley ... and to our knowledge he has never even met Bill Haley,'' said Barrowclough.

Barrowclough and his partnership have asked for triple damages, court costs and any profits earned by Grazino's band since Dec. 8, 1984, but a hearing on those issues has not been scheduled. The injunction will be in effect until the hearing.