Variable speed tool and variable speed control method
First Claim
1. A variable speed tool comprising:
- a switch;
a gearbox housing;
a motor;
an outputting shaft;
a multistage transmitting gear train and a gearshift ring coupled to the motor and the outputting shaft; and
a torque sensing ring, which is driven to rotate by the multistage transmitting gear train; and
wherein the variable speed tool further comprises a gearshift fork coupled to the gearshift ring and a first spring member which drives the gearshift fork in an axial direction of the gearshift ring, a second spring member being arranged between the torque sensing ring and the housing, one of the torque sensing ring and the gearshift fork forming a sliding groove and the other one forming a guiding portion movably received in the sliding groove, whereby when a load of the outputting shaft reaches a predetermined value, the torque sensing ring overcomes a spring force of the second spring member and rotates so that the gearshift fork is driven by the first spring member to take axial movement thereby moving the gearshift ring between a first position and a second position.
1 Assignment
0 Petitions
Accused Products
Abstract
The present invention has disclosed a variable speed tool and a variable speed control method. The tool includes a switch; a gearbox housing; a motor; an outputting shaft; a multistage transmitting gear train and a gearshift ring which are mated with the motor and the outputting shaft, the gearshift ring having inner teeth; a gearshift fork mated with the gearshift ring; a tension spring arranged between the gearbox housing and the gearshift fork; and a torque sensing ring provided with a sliding groove in which the gearshift fork is movably disposed. When the load of the outputting shaft has reached to a predetermined value, the torque sensing ring makes the gearshift fork move axially in the sliding groove under the action of the tension spring, thus bringing the gearshift ring to move axially. The variable speed tool of the present invention may automatically adjust the rotating speed and the torque of the outputting shaft according to a variation of the load torque.
-
Citations
50 Claims
-
1. A variable speed tool comprising:
-
a switch; a gearbox housing; a motor; an outputting shaft; a multistage transmitting gear train and a gearshift ring coupled to the motor and the outputting shaft; and a torque sensing ring, which is driven to rotate by the multistage transmitting gear train; and wherein the variable speed tool further comprises a gearshift fork coupled to the gearshift ring and a first spring member which drives the gearshift fork in an axial direction of the gearshift ring, a second spring member being arranged between the torque sensing ring and the housing, one of the torque sensing ring and the gearshift fork forming a sliding groove and the other one forming a guiding portion movably received in the sliding groove, whereby when a load of the outputting shaft reaches a predetermined value, the torque sensing ring overcomes a spring force of the second spring member and rotates so that the gearshift fork is driven by the first spring member to take axial movement thereby moving the gearshift ring between a first position and a second position. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16)
-
-
17. A variable speed tool comprising:
-
a housing; a power source; a power source switch; an outputting shaft; and a multistage transmitting gear train coupled to the power source and the outputting shaft; and the variable speed tool further comprising; a torque sensing device coupled to the multistage transmitting gear train, the torque sensing device having an axis of rotation and rotatable between a first angle and a second angle in response to a load torque of the outputting shaft, and a gearshift device coupled to the torque sensing device, the gearshift device being movable between a first axial position and a second axial position, the multistage transmitting gear train have different output torque when the gearshift device is in the first axial position and the second axial position; wherein one of the torque sensing device and the gearshift device forms a sliding groove and the other forms a guiding portion movably received in the sliding groove;
when variation of the load torque of the outputting shaft is within a range not exceeding a predetermined value, the torque sensing device is allowed to rotate within a range from the initial first angle and not exceeding the second angle so as to maintain the gearshift device in the first axial position where the multistage transmitting gear train provides a first outputting torque; and
when the load torque of the outputting shaft increases to the predetermined value, the torque sensing device rotates to the second angle and causes the gearshift device to move to the second axial position, whereby the multistage transmitting gear train changes from the first outputting torque to a second outputting torque and maintains the second outputting torque until the load torque varies from a first predetermined value to a second predetermined value. - View Dependent Claims (18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32)
-
-
33. The variable speed tool comprising:
-
a power source; a housing; a switch; an outputting shaft; and a multistage transmitting gear train coupled to the power source and the outputting shaft; and the variable speed tool comprising; a torque sensing device coupled to the multistage transmitting gear train, the torque sensing device having a center of rotation and being rotatable between first and second angular positions according to a load torque of the outputting shaft, and a gearshift device coupled to the torque sensing device, the gearshift device being movable between a first axial position and a second axial position, whereby when the gearshift device is at the first axial position and the second axial position, the multistage transmitting gear train shows different output characteristics; wherein a positioning device is provided for coupling to the torque sensing device, and when the torque sensing device rotates to the predetermined second angular position, the positioning device prevents the torque sensing device from rotating in response to variation of torque of the outputting shaft. - View Dependent Claims (34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46)
-
-
47. A variable speed control method for a variable speed tool applied for controlling the variable speed tool to change speed between a first outputting rotating speed and a second outputting rotating speed, wherein the variable speed tool comprises a power source, a housing, an outputting shaft, a multistage transmitting gear train coupled to the power source and the outputting shaft, a torque sensing device coupled to the multistage transmitting gear train and having an axis of rotation, and a gearshift device coupled to the torque sensing device, the gearshift device being movable between a first axial position and a second axial position, the outputting shaft providing a first output rotating speed and a second output rotating speed that are different when the gearshift device is located at the first axial position and the second axial position respectively, the variable speed control method comprising the following steps:
- (1) sensing an outputting torque of the outputting shaft by the torque sensing device;
(2) converting a variation of the outputting torque so sensed into a rotation angle of the torque sensing device;
(3) maintaining the gearshift device at the first axial position to have outputting shaft providing the first output rotating speed when the rotation angle of the torque sensing device is between a first angle and a second angle; and
(4) moving the gearshift device to the second axial position to have the outputting shaft providing the second output rotating speed when the rotation angle of the torque sensing device reaches the second angle. - View Dependent Claims (48, 49, 50)
- (1) sensing an outputting torque of the outputting shaft by the torque sensing device;
Specification