Installing Brother DCP7055W Scaer - tried everything!

Hello Ubuntu Experts!

It seems that I have a quite common problem, i can't get my DCP7055w scaer working. I tried everything posted on this forum and in the ubuntu wiki. Maybe you can help. Here some informations:

lsusb gives me the follwing:

Bus 002 Device 004: ID 0a5c:21ec Broadcom Corp.
Bus 002 Device 003: ID 046a:010d Cherry GmbH
Bus 002 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 005: ID 04f9:02ce Brother Industries, Ltd
Bus 001 Device 004: ID 046d:c069 Logitech, Inc. M-U0007 [Corded Mouse M500]
Bus 001 Device 003: ID 174c:5106 ASMedia Technology Inc. ASM1051 SATA 3Gb/s bridge
Bus 001 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

scanimage -L

device `bus2;dev1' is a Brother DCP-7055W USB scaer

scanimage -d "bus2:dev1" --format tiff > rawr.tiff
scanimage: open of device bus2:dev1 failed: Invalid argument

scanimage -d "bus1:dev5" --format tiff > rawr.tiff
scanimage: open of device bus1:dev5 failed: Invalid argument

dpkg -l | grep Brother

ii brother-udev-rule-type1 1.0.0-1 all Brother udev rule type 1
rc brscan 0.2.4 amd64 Brother CUPS Printer Definitions
ii brscan-skey 0.2.4-1 amd64 Brother Linux scaer S-KEY tool
ii brscan4 0.4.3-3 amd64 Brother Scaer Driver
ii dcp7055wcupswrapper:i386 3.0.1-1 i386 Brother DCP-7055W CUPS wrapper driver
ii dcp7055wlpr:i386 3.0.1-1 i386 Brother DCP-7055W LPR driver

Same problem for xsane and simple-scan, both give me the invalid argument message.
I also editet the libsane rules file , scaer is on a USB 2 Port and not on a hub.
I'm ruing Ubuntu 15.10.

I am totally out of ideas now, please help an ubuntu newbie!