A hydraulic brake caliper piston/plunger tool, comprising:
- a handle provided with a fluid reservoir and a fluid chamber, and pivotally connected with an operation lever;
- a barrel coaxially assembled with front and rear tubes respectively at two ends thereof, wherein the barrel and the rear tube are mounted at an upper section of the handle;
- and
- a shaft fixedly attached with a piston and fitted through the rear tube, the barrel and the front tube, wherein a return spring is fitted around the shaft in a central hole of the barrel, between the piston and the front tube, a circumferential passage that communicates with the central hole of the barrel is defined between the shaft and the rear tube, a front end of the shaft is adapted to be fitted with an accessory for a disc brake, and a rear end of the shaft is adapted to be connected with a turning tool for rotating the shaft;
- wherein a fluid circuit system is provided in the handle such that fluid chamber is communicated with the fluid reservoir and the circumferential passage, and the operation lever is spring-biased and provided with a plunger inserted into the fluid chamber;
- whereby alternately depressing and releasing the operation lever enables the plunger to force fluid to flow into the central hole of the barrel by way of the fluid circuit system and the circumferential passage, thus pushing the piston together with the shaft to move forward to push back a piston/plunger of the disc brake;
- wherein the fluid circuit system includes a first fluid feed passage, a second fluid feed passage, and a fluid supply passage, the first fluid feed passage defined in a middle section of the handle and connected with the fluid chamber, the second fluid feed passage defined in the upper section of the handle and connected between the first fluid feed passage and an inlet port of the rear tube that communicates with the circumferential passage, the fluid supply passage defined in the middle section of the handle and connected between the fluid chamber and the fluid reservoir;
- and
- wherein a communication space is defined between the upper and middle sections of the handle to communicate with the first and second fluid feed passages;
- the fluid circuit system further includes a fluid return passage defined in the middle section of the handle and connected between the communication space and the fluid reservoir.