CN201201205Y

CN201201205Y - Electric wrench

Info

Publication number: CN201201205Y
Application number: CNU2008200829984U
Authority: CN
Inventors: 戴冬军
Original assignee: Individual
Current assignee: Individual
Priority date: 2008-02-02
Filing date: 2008-02-02
Publication date: 2009-03-04
Anticipated expiration: 2018-02-02

Abstract

The utility model relates to an electric wrench, which comprises a pinion which is driven by a motor, a gear wheel which is meshed with the pinion, a ratchet seat, a pawl and a ratchet, wherein the pawl and the ratchet are fixed on the ratchet seat. The electric wrench is characterized in that the gear wheel is connected with a clutch which drives the ratchet seat to rotate through a clutch spring; the ratchet seat and both sides of the ratchet are provided with a left pawl pressure plate and a right pawl pressure plate; and one end of the left pawl pressure plate and one end of the right pawl pressure plate are fixed on both sides of the ratchet, and the other ends of the left and right pawl pressure plates are pressed on a lateral bevel of the pawl. The electric wrench adopts the pawl pressure plates to replace engagement and disengagement of a cylindrical pin and the pawl in the prior art, so as to make the ratchet generate an impulsive torque at intervals, thereby improving the impulsive torque of the electric wrench and the operation stability and the operation reliability of the electric wrench; due to use of the clutch and the clutch spring between the gear wheel and the ratchet seat, when the torque born by the ratchet is larger than the rated torque, the clutch spring which is clamped between the clutch and the gear wheel can generate more compression, so as to limit the relative motion of the clutch, thereby limiting the output torque of the ratchet within the rated torque and providing the function of overload protection to the electric wrench.

Description

A kind of electric wrench

Technical field

The utility model relates to a kind of motor-driven electric wrench, specifically refers to a kind of electric wrench with ratchet impact structure.

Background technology

Present normally used electric wrench, its structural representation as shown in Figure 3 and Figure 4, generally comprise motor 1 ', the pinion 2 ' that is connected with motor shaft, and the gear wheel 3 ' of pinion 2 ' engagement, be fixed on ratchet 9 ' and ratchet 8 ' on the pawl seat 7 ', be fixed on the pawl seat 7 ' and be positioned between ratchet 9 ' and the ratchet 8 ' two straight pins 6 ', be provided with Flywheel disc 4 ' between pawl seat 7 ' and the gear wheel 3 '.When motor 1 ' work, by pinion 2 ', the rotating drive pawl seat 7 ' rotation of gear wheel 3 ', two garden pins 6 ' on the pawl seat 7 ' break away from ratchet 8 ' under the centrifugal action of Flywheel disc 4 ', high speed rotary pawl 8 ' produces the 9 ' rotation of impact kinetic energy driving pawl with inactive state ratchet 9 ' the instantaneous contact, ratchet 8 ' suddenly reduces pawl seat 7 ' rotary speed with inactive state ratchet 9 ' the instantaneous generation reaction force that contacts, two garden pins, 6 ' rotary centrifugal force diminishes, two garden pins 6 ' reset under spring 5 ' pulling force, the two garden pins 6 ' that reset drive pawl seat 7 ' by ratchet 8 ' and begin rotation at a high speed again, go round and begin again, thereby screw or nut are firmly tightened in the shock insulation rotation between ratchet 9 ' circulation repeatedly.The use of electric wrench has improved the mechanization degree of operation, has alleviated working strength of workers.But still there is unsatisfactory place in the electric wrench of this kind structure; thereby this electric wrench drives ratchet 8 ' and drives pawl seat 7 ' and finish it and rotate at a high speed by being fixed on two straight pins 6 ' on the pawl seat 7 '; have that impulsive torque is on the low side, the shortcoming of poor reliability; and impulsive torque can not be regulated, no overload protection function.

Summary of the invention

Technical problem to be solved in the utility model is the situation at prior art, provides that a kind of impulsive torque is big, good reliability and have the electric wrench of overload protection function.

The utility model solves the problems of the technologies described above the technical scheme that is adopted: this electric wrench, comprise by motor-driven pinion, with the gear wheel of pinion, pawl seat, pawl-and-gearing, described pawl-and-gearing is fixed on the pawl seat, it is characterized in that: described gear wheel connects clutch, and clutch is by the rotation of clutch spring driving pawl seat; On pawl seat, the ratchet both sides are provided with left and right two ratchet pressing plates, an end of ratchet pressing plate is installed in the both sides of ratchet, other end pressure is on the prism of ratchet.Thereby what the utility model adopted that the ratchet pressing plate substitutes straight pin in the background technology and ratchet deciliter makes ratchet produce impulsive torque at interval, has improved the impulsive torque of electric wrench, has improved the operational stability and the reliability of electric wrench; The use of clutch and clutch spring between gear wheel and the pawl seat; can be during greater than nominal torque at the moment of torsion that bears when ratchet; the clutch spring that is clipped between clutch and the gear wheel can produce bigger compression; relative motion with the restriction clutch; thereby the output torque of ratchet is limited in the nominal torque, provides overload protection function to electric wrench.

Described pawl seat in the both sides of ratchet have respectively limiting plate and outside limiting plate, being provided with straight pin between the described inside and outside limiting plate is fixed on the pawl seat, described ratchet pressing plate shaft is located on this straight pin, the lateral surface of ratchet pressing plate is provided with projection, one end of spring is located on this projection, and the other end of spring supports and is located on the outer limiting plate.

Described ratchet pressing plate is the obtuse angle shape, and on the limiting plate, described spring supported and is located between ratchet pressing plate and the outer limiting plate in its underpart medial surface abutted in.

Compared with prior art, thereby because the impact rotation that the utility model has adopted the ratchet pressing plate to make pawl-and-gearing produce the interval property is unclamped or tightened screw or nut, and impulsive torque is big, reliable in action, stable; The use of clutch and clutch spring between gear wheel and the pawl seat simultaneously; can be during greater than nominal torque at the moment of torsion that bears when ratchet; the clutch spring that is clipped between clutch and the gear wheel can produce bigger compression; the relative motion of restriction clutch; thereby the output torque of ratchet is limited in the nominal torque; make the moment of torsion of electric wrench to regulate, provide overload protection function to electric wrench.

Description of drawings

Fig. 1 is the longitudinal sectional view of electric wrench among the embodiment of the present utility model;

Fig. 2 is the A-A cutaway view of Fig. 1;

Fig. 3 is the longitudinal sectional view of electric wrench in the utility model background technology;

Fig. 4 is the B-B cutaway view of Fig. 3.

The specific embodiment

Embodiment describes in further detail the utility model below in conjunction with accompanying drawing.

As depicted in figs. 1 and 2, this electric wrench comprises motor 1, the pinion 3 that drives by motor 1, with the gear wheel 4 of pinion 3 engagements, clutch 5 is embedded movably in gear wheel, described clutch spring 6 supports and is located between pawl seat 16 and the clutch 5.

As shown in Figure 2, described ratchet 10 is located at the middle position of pawl seat 16, in its both sides have respectively on pawl seat 16 limiting plate 8 and outside limiting plate 9, a left side straight pin 15 and right straight pin 19 be installed in respectively pawl seat 16 both sides and interior limiting plate 8 and outside between the limiting plate 9, described ratchet 11 is coupling on pawl seat 16 by great circle pin 12; Left pawl pressing plate 13 and right ratchet pressing plate 17 are the obtuse angle shape, axle is located on left straight pin 15 and the right straight pin 19 respectively, the lateral surface of left pawl pressing plate 13 and right ratchet pressing plate 19 is provided with projection 20, one end of

spring

14,18 is located in respectively on the corresponding projection 20, and the other end is resisted against on the outer limiting plate 9;

Spring

14,18 can make left pawl pressing plate 13 and right ratchet pressing plate 17 reset fast by its elastic reaction, and the top pressure of left pawl pressing plate 13 and right ratchet pressing plate 17 is on two inclined-planes of ratchet 11, and the bottom abuts on the interior limiting plate 8.

When motor 1 work, 4 rotations of pinion 3 rotating drive gear wheels, gear wheel 4 is by

clutch

5,16 rotations of clutch spring 6 driving pawl seats, pawl seat 16 just changeing make left pawl pressing plate 13 under centrifugal action around in pin 15 deflections of left garden, ratchet 11 also rotates under the action of centrifugal force that produces around big garden pin 12 deflections at pawl seat 16, the deflectable pawl 11 of high speed rotating and the ratchet of inactive state 10 instantaneous contacts, producing impact kinetic energy driving pawl 10 is just changeing, because ratchet 11 suddenly reduces pawl seat 16 rotary speeies with the ratchet 10 instantaneous generation reaction forces that contact of inactive state, left pawl pressing plate 13 rotary centrifugal forces diminish, left pawl pressing plate 13 resets under the pressure effect of spring 14, the left pawl pressing plate 13 that resets acts on ratchet 11 and makes it to break away from ratchet 10, the pawl seat 16 that has broken away from resistance begins rotation at a high speed again, go round and begin again, thereby screw or nut are tightened in the shock insulation rotation between ratchet 10 circulations repeatedly.

In the time of need unclamping screw or nut, motor 1 is by pinion 3, gear wheel 4,

clutch

5 and 16 counter-rotatings of clutch spring 6 driving pawl seats, make right ratchet pressing plate 17 under action of centrifugal force around in pin 19 deflections of right garden, ratchet 11 also under action of centrifugal force around big garden pin 12 deflections, deflectable pawl 11 with pawl seat 16 high speed rotating produces 10 counter-rotatings of impact kinetic energy driving pawl with inactive state ratchet 10 instantaneous contacts, producing reaction force suddenly reduces pawl seat 16 rotary speeies, right ratchet pressing plate 17 rotary centrifugal forces diminish, reset at right spring 18 pressure bottom right ratchet pressing plates 17 simultaneously, the right ratchet pressing plate 17 that resets acts on ratchet 11 and makes it to break away from ratchet 10, the pawl seat 16 that has broken away from resistance begins rotation at a high speed again, go round and begin again, thereby screw or nut are unclamped in the shock insulation rotation between ratchet 10 circulations repeatedly.

In the above-mentioned work, the impulsive torque of ratchet 10 is to rotate by pinion 3 to drive gear wheel 4, gear wheel 4,

clutch

5 and 16 rotations of clutch spring 6 driving pawl seats successively, and the interaction by left pawl pressing plate 13, right ratchet pressing plate 17 and ratchet 11 makes ratchet 10 produce that forward or reverse impulsive force at interval produced.

The moment of torsion that bears when ratchet 10 is during greater than nominal torque; be located at clutch spring 6 between clutch 5 and the gear wheel 4 and can adjust the extruding degree of its elastic force automatically; keep ratchet 10 output torques and be not more than nominal torque, thereby give this electric wrench overload protection function.

Claims

1, a kind of electric wrench, include motor-driven pinion, with the gear wheel of pinion, pawl seat, pawl-and-gearing, described pawl-and-gearing is fixed on the pawl seat, it is characterized in that: described gear wheel connects clutch, and clutch is by the rotation of clutch spring driving pawl seat; On pawl seat, the ratchet both sides are provided with left and right two ratchet pressing plates, an end of ratchet pressing plate is installed in the both sides of ratchet, other end pressure is on the prism of ratchet.

2, electric wrench according to claim 1, it is characterized in that: described pawl seat in the both sides of ratchet have respectively limiting plate and outside limiting plate, being provided with straight pin between the described inside and outside limiting plate is fixed on the pawl seat, described ratchet pressing plate shaft is located on this straight pin, the lateral surface of ratchet pressing plate is provided with projection, one end of spring is located on this projection, and the other end of spring supports and is located on the outer limiting plate.

3, electric wrench according to claim 2 is characterized in that: described ratchet pressing plate is the obtuse angle shape, and its underpart medial surface abuts on the interior limiting plate.