Electric ratchet wrench

1. An electric ratchet wrench comprising:

a body including first and second ends along a first axis;

a driving device mounted to the first end of the body, with the driving device adapted to drive a fastener about a second axis perpendicular to the first axis;

a power device mounted to the second end of the body, with the power device adapted to provide electricity for operation;

a first transmission device mounted between the driving device and the power device, with the first transmission device rotatably received in the body and connected to the driving device, and with the first transmission device including an extension having a first shape;

a second transmission device mounted between the driving device and the power device, with the second transmission device rotatably mounted in the body and connected to the power device; and

a clutch device mounted between the first transmission device and the second transmission device, with the clutch device switchable between a coupling state when a resistance smaller than a torque output by the power device is encountered while the driving device is driving the fastener to rotate about the second axis and a disengagement state when a resistance larger than the torque output by the power device is encountered at a position while the driving device is driving the fastener to rotate about the second axis, wherein the clutch device includes a first clutch member mounted to the first transmission device, a second clutch member mounted to the second transmission device, and an elastic element abutting the first clutch member, with the first clutch member and the second clutch member disengageably engaged with each other; wherein the first clutch member comprises a center through-opening having a complementary shape to the first shape of the extension of the first transmission device, wherein the through-opening is configured to slidingly-receive the extension of the first transmission device; wherein the clutch device is configured to switch between the coupling state and the disengagement state at least by the first clutch member sliding along an outer portion of the extension of the first transmission device via the through-opening, generally along the first axis;

with the clutch device in the coupling state, the power device drives the second transmission device and the clutch device to drive the first transmission device to rotate about the first axis, and the driving device is rotated to continuously drive the fastener to rotate about the second axis without moving the body,

with the clutch device in the disengagement state, the torque of the power device is not permitted to be transmitted through the second transmission device to the first transmission device, the body is manually rotated to overcome the resistance and to forcibly drive the fastener through the position via the driving device, wherein the clutch device returns to the coupling state after the fastener passes through the position, and wherein the driving device again drives the fastener to rotate about the second axis without moving the body,

with the clutch device in the disengagement state, the first clutch member and the second clutch member repeatedly engage with and disengage from each other, the one of the first clutch member and the second clutch member compresses the elastic element, the body is manually rotated to overcome the resistance and to forcibly drive the fastener through the position via the driving device, and the clutch device returns to the coupling state under action of the elastic element after the fastener passes through the position; and

wherein the elastic element is between the first transmission device and the first clutch member.

2. The electric ratchet wrench as claimed in claim 1 , wherein the first clutch member and the second clutch member engage with each other when the clutch device is in the coupling state, and wherein the first clutch member and the second clutch member are in a semi-coupling state repeatedly engaging with and disengaging from each other when the clutch device is in the disengagement state.

3. The electric ratchet wrench as claimed in claim 2 , with the first clutch member including at least one first clutch portion, with the second clutch member including at least one second clutch portion, and with the at least one first clutch portion and the at least one second clutch portion disengageably engaged with each other.

4. The electric ratchet wrench as claimed in claim 3 , with the first transmission device including a first transmission member, with the first transmission member including a first connection end, a second connection end, and a body portion between the first connection end and the second connection end, with the first connection end connected to the driving device, and with the first clutch member slideably mounted on the second connection end.

5. The electric ratchet wrench as claimed in claim 3 , with the second transmission device including a second transmission member, with the second transmission member including a first coupling end, a second coupling end, and a coupling section between the first coupling end and the second coupling end, the second clutch member slideably mounted on the first coupling end, and with the second coupling end connected to the power device.

6. The electric ratchet wrench as claimed in claim 1 , with the body further including a compartment located in the second end of the body and a connection hole in communication with the compartment, with the power device received in the compartment, with the first transmission device and the clutch device rotatably mounted in the connection hole, and with the second transmission device rotatably mounted in the compartment.

7. The electric ratchet wrench as claimed in claim 6 , with the connection hole including a first section having a first inner diameter and a second section in communication with the first section and the compartment and having a second inner diameter larger than the first inner diameter, with the first transmission device rotatably mounted in the first section, with the clutch device rotatably mounted in the second section, and with the second transmission device rotatably mounted between the compartment and the second section of the connection hole.

8. The electric ratchet wrench as claimed in claim 1 , with the driving device including a driving member rotatably mounted in the first end of the body and a first ring gear rotatably mounted to the driving member for driving the driving member to rotate, with the first ring gear including a side toothed portion on an end face thereof, and with the first transmission member including a gear meshed with the side toothed portion of the first ring gear.

9. The electric ratchet wrench as claimed in claim 8 , with the body including a driving hole having an inner periphery with a toothed portion, with the driving device further including a second ring gear, a pawl device, and a direction switching device, with the second gear ring rotatably mounted to the driving member and spaced from the first ring gear, with the first ring gear further including an inner toothed portion on an inner periphery thereof, with the second ring gear including a side toothed portion on an end face thereof and an inner toothed portion on an inner periphery thereof, with the inner toothed portions of the first and second ring gears selectively engaged with the pawl device, with the side toothed portion of the second ring gear meshed with the gear of the first transmission member, with the pawl device including two primary pawls, a first secondary pawl, and a second secondary pawl, with each of the two primary pawls configured to selectively mesh with the toothed portion of the body, with the first secondary pawl configured to selectively mesh with the inner toothed portion of the first ring gear, with the second secondary pawl configured to selectively mesh with the inner toothed portion of the second ring gear, with the direction switching device including a direction switching rod extending through the driving member, with the direction switching rod pivotable relative to the driving member between two positions respectively corresponding to a driving direction and a non-driving direction, wherein when the direction switching rod pivots between the two positions, an engagement status between each of the two primary pawls and the toothed portion of the body and an engagement status between the first and second secondary pawls and the first and second ring gears are changed to provide a direction switching function.

10. The electric ratchet wrench as claimed in claim 5 , with the body further including a compartment located in the second end of the body and a connection hole in communication with the compartment, with the Power device received in the compartment, with the first transmission device and the clutch device rotatably mounted in the connection hole, and with the second transmission device rotatably mounted in the compartment.

11. The electric ratchet wrench as claimed in claim 10 , with the connection hole including a first section having a first inner diameter and a second section in communication with the first section and the compartment and having a second inner diameter larger than the first inner diameter, with the first transmission device rotatably mounted in the first section, with the clutch device rotatably mounted in the second section, and with the second transmission device rotatably mounted between the compartment and the second section of the connection hole.

12. The electric ratchet wrench as claimed in claim 11 , with the driving device including a driving member rotatably mounted in the first end of the body and a first ring gear rotatably mounted to the driving member for driving the driving member to rotate, with the first ring gear further including a side toothed portion on an end face thereof, and with the first transmission member further including a gear meshed with the side toothed portion of the first ring gear.

13. The electric ratchet wrench as claimed in claim 12 , with the body including a driving hole having an inner periphery with a toothed portion, with the driving device further including a second ring gear, a pawl device, and a direction switching device, with the second gear ring rotatably mounted to the driving member and spaced from the first ring gear, with the first ring gear further including an inner toothed portion on an inner periphery thereof, with the second ring gear including a side toothed portion on an end face thereof and an inner toothed portion on an inner periphery thereof, with the inner toothed portions of the first and second ring gears selectively engaged with the pawl device, with the side toothed portion of the second ring gear meshed with the gear of the first transmission member, with the pawl device including two primary pawls, a first secondary pawl, and a second secondary pawl, with each of the two primary pawls configured to selectively mesh with the toothed portion of the body, with the first secondary pawl configured to selectively mesh with the inner toothed portion of the first ring gear, with the second secondary pawl configured to selectively mesh with the inner toothed portion of the second ring gear, with the direction switching device including a direction switching rod extending through the driving member, with the direction switching rod pivotable relative to the driving member between two positions respectively corresponding to a driving direction and a non-driving direction, wherein when the direction switching rod pivots between the two positions, an engagement status between each of the two primary pawls and the toothed portion of the body and an engagement status between the first and second secondary pawls and the first and second ring gears are changed to provide a direction switching function.

14. An electric ratchet wrench comprising:

a body including first and second ends along a first axis;

a driving device mounted to the first end of the body, with the driving device adapted to drive a fastener about a second axis perpendicular to the first axis;

a power device mounted to the second end of the body, with the power device adapted to provide electricity for Operation;

a first transmission device mounted between the driving device and the power device, with the first transmission device rotatably received in the body and connected to the driving device, and with the first transmission device including an extension having a first shape;

a second transmission device mounted between the driving device and the power device, with the second transmission device rotatably mounted in the body and connected to the power device; and

a clutch device mounted between the first transmission device and the second transmission device, with the clutch device switchable between a coupling state and a disengagement state due to a resistance, wherein the clutch device includes a first clutch member mounted to the first transmission device, a second clutch member mounted to the second transmission device, and an elastic element abutting one of the first clutch member and the second clutch member, with the first clutch member and the second clutch member disengageably engaged with each other; wherein the first clutch member comprises a center through-opening having a complementary shape to the first shape of the extension of the first transmission device, wherein the through-opening is configured to slidingly-receive the extension of the first transmission device; wherein the clutch device is configured to switch between the coupling state and the disengagement state at least by the first clutch member sliding along an outer portion of the extension of the first transmission device via the through-opening, generally along the first axis;

with the clutch device in the coupling state, the power device drives the second transmission device and the clutch device to drive the first transmission device to rotate about the first axis, and the driving device is rotated to continuously drive the fastener to rotate about the second axis without moving the body, with the clutch device in the disengagement state, torque of the power device is not permitted to be transmitted through the second transmission device to the first transmission device, the body is manually rotated to overcome the resistance and to forcibly drive the fastener through a position via the driving device, wherein the clutch device returns to the coupling state after the fastener passes through the position, and wherein the driving device again drives the fastener to rotate about the second axis without moving the body, and

with the clutch device in the disengagement state, the first clutch member and the second clutch member repeatedly engage with and disengage from each other, the one of the first clutch member and the second clutch member compresses the elastic element, the body is manually rotated to overcome the resistance and to forcibly drive the fastener through the position via the driving device, and the clutch device returns to the coupling state under action of the elastic element after the fastener passes through the position.

15. An electric ratchet wrench comprising:

a body including first and second ends along a first axis;

a driving device mounted to the first end of the body, with the driving device adapted to drive a fastener about a second axis perpendicular to the first axis;

a power device mounted to the second end of the body, with the power device adapted to provide electricity for operation;

a first transmission device mounted between the driving device and the power device, with the first transmission device rotatably received in the body and connected to the driving device, and with the first transmission device including an extension having a first shape;

a second transmission device mounted between the driving device and the power device, with the second transmission device rotatably mounted in the body and connected to the power device; and

a clutch device mounted between the first transmission device and the second transmission device, with the clutch device switchable between a coupling state when a resistance smaller than a torque output by the power device is encountered while the driving device is driving the fastener to rotate about the second axis and a disengagement state when a resistance larger than the torque output by the power device is encountered at a position while the driving device is driving the fastener to rotate about the second axis, wherein the clutch device includes a first clutch member mounted to the first transmission device, a second clutch member mounted to the second transmission device, and an elastic element, with the first clutch member and the second clutch member disengageably engaged with each other; wherein the first clutch member comprises a center through-opening having a complementary shape to the first shape of the extension of the first transmission device, wherein the through-opening is configured to slidingly-receive the extension of the first transmission device; wherein the clutch device is configured to switch between the coupling state and the disengagement state at least by the first clutch member sliding along an outer portion of the extension of the first transmission device via the through-opening, generally along the first axis;

with the clutch device in the coupling state, the power device drives the second transmission device and the clutch device to drive the first transmission device to rotate about the first axis, and the driving device is rotated to continuously drive the fastener to rotate about the second axis without moving the body,

with the clutch device in the disengagement state, the torque of the power device is not permitted to be transmitted through the second transmission device to the first transmission device, the body is manually rotated to overcome the resistance and to forcibly drive the fastener through the position via the driving device, wherein the clutch device returns to the coupling state after the fastener passes through the position, and wherein the driving device again drives the fastener to rotate about the second axis without moving the body, and

with the clutch device in the disengagement state, the first clutch member and the second clutch member repeatedly engage with and disengage from each other, the one of the first clutch member and the second clutch member compresses the elastic element, the body is manually rotated to overcome the resistance and to forcibly drive the fastener through the position via the driving device, and the clutch device returns to the coupling state under action of the elastic element after the fastener passes through the position;

wherein the first clutch member and the second clutch member engage with each other when the clutch device is in the coupling state, and wherein the first clutch member and the second clutch member are in a semi-coupling state repeatedly engaging with and disengaging from each other when the clutch device is in the disengagement state; and

with the first clutch member including at least one first clutch portion, with the second clutch member including at least one second clutch portion, and with the at least one first clutch portion and the at least one second clutch portion disengageably engaged with each other.

16. An electric ratchet wrench comprising:

a body including first and second ends along a first axis;

a driving device mounted to the first end of the body, with the driving device adapted to drive a fastener about a second axis perpendicular to the first axis;

a power device mounted to the second end of the body, with the power device adapted to provide electricity for operation;

a first transmission device mounted between the driving device and the power device, with the first transmission device rotatably received in the body and connected to the driving device, and with the first transmission device including an extension having a first shape;

a second transmission device mounted between the driving device and the power device, with the second transmission device rotatably mounted in the body and connected to the power device; and

a clutch device mounted between the first transmission device and the second transmission device, with the clutch device switchable between a coupling state when a resistance smaller than a torque output by the power device is encountered while the driving device is driving the fastener to rotate about the second axis and a disengagement state when a resistance larger than the torque output by the power device is encountered at a position while the driving device is driving the fastener to rotate about the second axis, wherein the clutch device includes a first clutch member mounted to the first transmission device, a second clutch member mounted to the second transmission device, and an elastic element abutting the first clutch member, with the first clutch member and the second clutch member disengageably engaged with each other; wherein the first clutch member comprises a center through-opening having a complementary shape to the first shape of the extension of the first transmission device, wherein the through-opening is configured to slidingly-receive the extension of the first transmission device; wherein the clutch device is configured to switch between the coupling state and the disengagement state at least by the first clutch member sliding along an outer portion of the extension of the first transmission device via the through-opening, generally along the first axis;

with the clutch device in the coupling state, the power device drives the second transmission device and the clutch device to drive the first transmission device to rotate about the first axis, and the driving device is rotated to continuously drive the fastener to rotate about the second axis without moving the body,

with the clutch device in the disengagement state, the torque of the power device is not permitted to be transmitted through the second transmission device to the first transmission device, the body is manually rotated to overcome the resistance and to forcibly drive the fastener through the position via the driving device, wherein the clutch device returns to the coupling state after the fastener passes through the position, and wherein the driving device again drives the fastener to rotate about the second axis without moving the body,

with the clutch device in the disengagement state, the first clutch member and the second clutch member repeatedly engage with and disengage from each other, the one of the first clutch member and the second clutch member compresses the elastic element, the body is manually rotated to overcome the resistance and to forcibly drive the fastener through the position via the driving device, and the clutch device returns to the coupling state under action of the elastic element after the fastener passes through the position; and

wherein the elastic element is between the first transmission device and the first clutch member.

17. The electric ratchet wrench as claimed in claim 15 , with the first clutch member further including a connection portion on an end face of the first clutch member opposite to the first transmission device, with the at least one first clutch portion provided on an inner periphery of the connection portion, with the second clutch member rotatably connected to the connection portion of the first clutch member, with the second clutch member including a through-hole, and with the at least one second clutch portion slideably received in the through-hole and disengageably engaged with the at least one first clutch portion.

18. The electric ratchet wrench as claimed in claim 17 , with the body further including a compartment located in the second end of the body and a connection hole in communication with the compartment, with the Power device received in the compartment, with the first transmission device and the clutch device rotatably mounted in the connection hole, and with the second transmission device rotatably mounted in the compartment.

19. The electric ratchet wrench as claimed in claim 18 , with the connection hole including a first section having a first inner diameter and a second section in communication with the first section and the compartment and having a second inner diameter larger than the first inner diameter, with the first transmission device rotatably mounted in the first section, with the clutch device rotatably mounted in the second section, and with the second transmission device rotatably mounted between the compartment and the second section of the connection hole.

20. The electric ratchet wrench as claimed in claim 19 , with the driving device including a driving member rotatably mounted in the first end of the body and a first ring gear rotatably mounted to the driving member for driving the driving member to rotate, with the first ring gear including a side toothed portion on an end face thereof, with the first transmission member including a gear meshed with the side toothed portion of the first ring gear, with the body including a driving hole having an inner periphery with a toothed portion, with the driving device further including a second ring gear, a pawl device, and a direction switching device, with the second gear ring rotatably mounted to the driving member and spaced from the first ring gear, with the first ring gear further including an inner toothed portion on an inner periphery thereof, with the second ring gear including a side toothed portion on an end face thereof and an inner toothed portion on an inner periphery thereof, with the inner toothed portions of the first and second ring gears selectively engaged with the pawl device, with the side toothed portion of the second ring gear meshed with the gear of the first transmission member, with the pawl device including two primary pawls, a first secondary pawl, and a second secondary pawl, with each of the two primary pawls configured to selectively mesh with the toothed portion of the body, with the first secondary pawl configured to selectively mesh with the inner toothed portion of the first ring gear, with the second secondary pawl configured to selectively mesh with the inner toothed portion of the second ring gear, with the direction switching device including a direction switching rod extending through the driving member, with the direction switching rod pivotable relative to the driving member between two positions respectively corresponding to a driving direction and a non-driving direction, wherein when the direction switching rod pivots between the two positions, an engagement status between each of the two primary pawls and the toothed portion of the body and an engagement status between the first and second secondary pawls and the first and second ring gears are changed to provide a direction switching function.