We present the results of a comprehensive investigation on the evolution of spectral and timing properties of the Galactic black hole candidate 4U?1630-47 during its spectral transitions. In particular, we show how a scaling of the correlation of the photon index of the Comptonized spectral component Γ with low-frequency quasi-periodic oscillations (QPOs), ν L , and mass accretion rate, , can be applied to the black hole mass and the inclination angle estimates. We analyze the transition episodes observed with the Rossi X-Ray Timing Explorer and BeppoSAX satellites. We find that the broadband X-ray energy spectra of 4U?1630-47 during all spectral states can be modeled by a combination of a thermal component, a Comptonized component, and a red-skewed iron-line component. We also establish that Γ monotonically increases during transition from the low-hard state to the high-soft state and then saturates for high mass accretion rates. The index saturation levels vary for different transition episodes. Correlations of Γ versus ν L also show saturation at Γ ~ 3. and Γ-ν L correlations with their index saturation revealed in 4U?1630-47 are similar to those established in a number of other black hole candidates and can be considered as an observational evidence for the presence of a black hole in these sources. The scaling technique, which relies on XTE?J1550-564, GRO 1655-40, and H1743-322 as reference sources, allows us to evaluate a black hole mass in 4U?1630-47 yielding M BH ~ 10 ± 0.1 solar masses and to constrain the inclination angle of i 70°.
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