Knee pad bracket

A knee pad bracket, comprising:

• a first frame (1), having a first arc portion (2) and two first support rods (3) that are disposed at two ends of the first arc portion (2) respectively;
• a second frame (4), having a second arc portion (5) and two second support rods (6) that are disposed at two ends of the second arc portion (5) individually, wherein the first arc portion (2) corresponds to the second arc portion (5), in order to define a first accommodation room (7) that accommodates a thigh of a human being;
• a third frame (8), which corresponds to the first frame (1), having a third arc portion (9) and two third support rods (10) that are disposed at two ends of the third arc portion (9) respectively;
• a fourth frame (11), which corresponds to the second frame (4), having a fourth arc portion (12) and two fourth support rods (13) that are disposed at two ends of the fourth arc portion (12) individually, in order to define a second accommodation room (14) that is connected with the first accommodation room (7) and accommodates a calf of the human being;
• two pivot axes (15), detachably and pivotally disposed at two corresponding sides of the first frame (1), the second frame (4), the third frame (8), and the fourth frame (11), wherein each of the two pivot axes (15) is pivotally connected with one of the first support rods (3), one of the second support rods (6), one of the third support rods (10), and one of the fourth support rods (13);
• a first elastic element (17), which two ends being disposed on a first side of the first frame (1) and a first side of the second frame (4), wherein the first side of the first frame (1) and the first side of the second frame (4) are on the same side, and wherein the first side of the first frame (1) is opposite to a second side of the first frame (1) corresponding to the first accommodation room (7), and the first side of the second frame (4) is opposite to a second side of the second frame (4) corresponding to the first accommodation room (7);
• and
• a second elastic element (18), which two ends being disposed on a first side of the third frame (8) and a first side of the fourth frame (11), wherein the first side of the third frame (8) and the first side of the fourth frame (11) are on the same side, and wherein the first side of the third frame (8) is opposite to a second side of the third frame (8) corresponding to the second accommodation room (14), and the first side of the fourth frame (11) is opposite to a second side of the fourth frame (11) corresponding to the second accommodation room (14), wherein an angle Θ1 is between a central axis of the first arc portion (2) and a central axis of the first support rod (3) and faces to the third frame (8), the angle Θ1 being between 100 degrees and 135 degrees;
• an angle Θ2 is between a central axis of the second arc portion (5) and a central axis of the second support rod (6) and faces to the fourth frame (11), the angle Θ2 being between 100 degrees and 135 degrees;
• an angle Θ3 is between a central axis of the third arc portion (9) and a central axis of the third support rod (10) and faces to the first frame (1), the angle Θ3 being between 100 degrees and 135 degrees;
• and an angle Θ4 is between a central axis of the fourth arc portion (12) and a central axis of the fourth support rod (13) and faces to the second frame (4), the angle Θ4 being between 100 degrees and 135 degrees.