JPH1015909A - Contact arm for motor-driven nailing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate visibility and positioning of nailing position by decreasing the vol. of a contact arm mechanism of a nailing machine. SOLUTION: A first lever L1 and a second lever L2 are coaxially pivoted in a housing of a nailing machine. The front part of the lever L1 is hooked with a contact arm 26 in a nose and the back part of the lever L2 faces to a contact detecting switch 27. A cam 28 fitted to the lever L1 is prepd. by integrally molding a cam part 28a with a large diameter and a cam part 28b with a small diameter both having the same width in lift changing. When the cam 28 is rotated, the angle of opening between the levers L1 and L2 is changed by the cam part 28b with a small diameter and the elevating limit of the contact arm 26 is controlled by changing the interval between the cam part 28a with a large diameter and a lever stopper 37. When the contact arm is elevated, the contact detecting switch 27 is pushed and a detecting signal is inputted into a control part and regardless of the rotating position of the cam 28, the stroke by which the second lever L2 pushes a push button of the contact detecting switch 27 is const.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a contact arm of an electric nailing machine, and more particularly to a contact arm having a function of adjusting a driving depth.

[0002]

2. Description of the Related Art A nailing machine for hand-held operation using compressed air or electricity as a power source has an actuating device constituted by a contact arm and a trigger lever provided near a nose having a nail injection port. The contact arm is slidably mounted along the nose in parallel with the nail ejection direction, and is urged by a spring in a direction protruding from the nose.

In an electric nailing machine, a push button of a microswitch in a nailing machine housing is configured to be turned on and off by an upper end portion of a contact arm, and the microswitch and a microswitch operated by a trigger lever are operated. Are connected to a logic circuit to form a starting circuit. Then, by pressing the contact arm against the nailing target and rotating the trigger lever, the two micro switches are turned on, the motor is started, and the nail is ejected by the driver.

Further, the contact arm can be divided into two parts and the total length can be changed by adjusting screws, and the nose can be changed by changing the amount of protrusion of the contact arm from the nose or the distance between the upper part of the contact arm and the upper slide stopper. By adjusting the distance between the nail and the surface to be driven, the nail driving depth can be adjusted.

[0005]

There are various types of nailing machines according to the diameter of nails to be used. However, when designing a nailing machine for fine finishing nails used for interior construction work, etc. It is necessary to make the nose thinner in view of the visibility of the driving position and the ease of driving into the corner. However, when the structure of the conventional contact arm is applied, the driving depth adjusting mechanism and the like are arranged around the nose portion, and it is difficult to reduce the size of the nose portion, and the visibility and the easiness of the driving positioning decrease. Will do.

Therefore, there arises a technical problem to be solved in order to reduce the size of the nose portion as much as possible, and an object of the present invention is to solve the above problem.

[0007]

SUMMARY OF THE INVENTION The present invention proposes to achieve the above object. A contact arm slidable in a nail injection direction is provided at a nose portion of a nailing machine, and a spring is provided. The tip of the contact arm protrudes from the tip of the nose in the direction of nail ejection through the other end of the contact arm, and the other end of the contact arm faces the push button of the contact detection switch in the nailer housing. In the contact arm of the electric nailing machine formed so as to turn on and off the contact detection switch by the sliding operation, a plate-shaped contact arm slidable in a nail injection direction is accommodated in a nose, and a lever is provided in the housing. Of the lever, the front end of the lever is engaged with the contact arm, and the rear end of the lever is connected to the contact detection switch. Along with the push button, the contact detection switch is formed to be turned on and off via the lever, and a cam is pivotally mounted on a side surface of the lever, and a click stop mechanism is interposed on the cam, A contact arm for an electric nailing machine, characterized in that a stopper is provided in a housing to regulate the range of elevation of the lever, the stopper is opposed to the cam, and the elevation limit of the contact arm is switched according to the rotational position of the cam. It is.

A plate-shaped contact arm slidable in the nail injection direction is accommodated in a nose, and a first lever and a second lever are coaxially pivotally mounted in the housing, and a first lever is provided. The front end of the first lever is engaged with the contact arm, the rear end of the second lever is opposed to the push button of the contact detection switch, and a cam is pivotally attached to the middle side of the first lever and clicked on the cam. With a stop mechanism,
A second lever is pressed against the cam by a spring, and a stopper is provided on the housing to limit a rising range of the first and second levers. The stopper is opposed to the cam. The ascending limit and the relative angle between the first lever and the second lever are freely switchable, and the rotational position of the rear end of the second lever at the ascending limit of the contact arm is constant regardless of the rotational position of the cam. The present invention provides a contact arm for an electric nailing machine.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows a portable electric nailing machine 1 in which a driving mechanism of a driver 3 and a control circuit board 4 are built in a housing 2, and a rechargeable battery pack 5 is mounted on an end of a grip 2 a. A nail magazine 7 connected to the back of the nose 6, which is a nail injection unit, accommodates connected nails in which a large number of nails are bonded in parallel, and is connected by springs and feed claws (not shown) in the nail magazine 7. A nail is fed into the nose 6.

The power of the DC motor 8 in the housing 2 is
Front plunger pulling device 10 via planetary gear device 9
Is transmitted to The planetary gear device 9 reduces the rotation of the pinion 11 of the DC motor 8 to three stages via an internal gear ring gear 12 fixed to the housing 2 and three rows of planetary gears 13 meshing with the internal gear ring gear 12, The lowermost spur gear 14 of the plunger lifting device 10 is driven.

As shown in FIG. 2, the plunger lifting device 1
0 indicates three spur gears 14, 15, 16 arranged vertically
The spur gears 14, 15 and 16 have rollers 17 and 1 at positions displaced from the rotation center on the front surface, respectively.
8 and 19 are mounted on the shaft, and the rollers 17, 18 and 19 revolve as the spur gears 14, 15 and 16 rotate.

As shown in FIG. 1, spur gears 14, 15, 1
A plunger holder 20 is formed in the vertical direction in front of 6, and a plunger 21 is loosely fitted in the plunger holder 20. The plunger 21 has a compression coil spring 22 interposed between the inner top surface of the plunger holder 20 and the plunger 21.
Urged downwards. The driver 3 is fixed to the front surface of the plunger 21, and the driver 3 moves up and down in the gap between the front and rear guide plates 6 a and 6 b of the nose 6.

On the back surface of the plunger 21, there are formed convex portions 21a, 21b, 21c projecting rearward.
When the spur gears 14, 15 and 16 rotate, first, the roller 17 of the lower spur gear 14 engages with the lower convex portion 21a to push up the plunger 21 to near the top dead center of the roller 17, and at this time the middle spur The roller 18 of the gear 15 is engaged with the convex part 21b at the middle stage to further pull the plunger 21 upward. Subsequently, the roller 19 of the upper spur gear 16 is moved to the upper convex portion 21c.
And pulls the plunger 21 up to just before the top dead center.

A cycle end detection switch 23 is provided above the plunger holder 20, and a plunger 2 is provided.
When the upper end of 1 presses the cycle end detection switch 23, a cycle end signal is output to the control circuit, and the control circuit applies an electromagnetic brake to the DC motor 8 to stop the plunger 21 and the driver 3 at the upper standby position.

The nail driving circuit includes a trigger operation detection switch 25 operated by a trigger lever 24 provided at a base of the grip portion 2a of the housing 2, and a contact detection switch 27 operated by a contact arm 26 in the nose 6. And the contact arm 2
The DC motor 8 is started by touching and pushing the object 6 into the object to be driven and operating the trigger lever 24 with a finger. This activates the plunger lifting device 10,
The engagement between the roller 19 of the upper spur gear 16 and the convex portion 21c of the plunger 21 is released, the plunger 21 is rapidly lowered in the plunger holder 20 by the compression coil spring 22, and the driver 3 ejects the nail in the nose 6. I do.

A contact arm 26 is inserted between the plates 6a and 6b before and after the nose 6 so as to be able to move up and down.
As shown in FIG. 3, a vertical groove 26a for guiding a nail is formed on the back surface of the contact arm 26. Housing 2
A first lever L1 and a second lever L2 are coaxially pivotally mounted therein, and a front end of the first lever L1 is engaged with a lever locking hole 26b provided in an upper portion of the contact arm 26. . The rear part of the second lever L2 rises upward and faces the push button of the contact detection switch 27.

As shown in FIGS. 3 and 4, a cam 28 is rotatably mounted on an intermediate portion of the first lever L1, and a knob 29 is fitted on a shaft 28c of the cam 28 to make the cam 28 optional. Can be rotated to the position. The cam 28 is a large diameter cam portion 2
8a and the small-diameter cam portion 28b are coaxially and integrally formed, the large-diameter cam portion 28a is constituted by a flat portion whose distance from the rotation center changes in five steps, and the small-diameter cam portion 28b is formed by the large-diameter cam portion 28a. Cams having the same lift change amount are constituted by curved surfaces.

As shown in FIG. 4, a cam shaft 28c is inserted into a hole 30 at an intermediate portion of the first lever L1, a sleeve 31 and a compression coil spring 32 are inserted through the cam shaft 28c,
The cam 28 is rotatably mounted by screwing the knob 29 to the tip of 8c. Five notches n are radially provided on the lever contact surface of the sleeve 31 that meshes with the knob 29, and the notch n and the convex portion 33 formed on the side surface of the first lever L1 constitute a click stop mechanism. Have been. The sleeve 31 is first compressed by a compression coil spring 32.
Is pressed against the side surface of the lever L1, and the notch n and the projection 3
By engaging the cam 3 with the cam 3, the cam 28 is fixed at one of five fixed positions.

The position of the second lever L2 corresponding to the small-diameter cam portion 28b near the front end is cut out in a gate shape to form a cam contact surface 34, and the first lever L1 and the second lever L2 are formed.
Are pivotally attached to the housing 2, the small-diameter cam portion 28
b contacts the cam contact surface 34. As shown in FIG. 2, the knob 29 is screwed to a cam shaft 28c that protrudes outward from an elongated hole 2b provided on a side surface of the housing 2.

As shown in FIG. 1, a compression coil spring 36 is interposed between the upper surface of the distal end of the second lever L2 and the spring receiving portion 35 of the housing 2 so that the front of the second lever L2 is downward. To the cam contact surface 34 of the second lever L2.
Presses against the small-diameter cam portion 28b and urges the first lever L1 downward so that the contact arm 26 protrudes in the nail ejection direction.

A stopper 37 is provided in the housing 2 above the large-diameter cam portion 28a. When the contact arm 26 is brought into contact with the object to be driven and pushed in, the upper surface of the large-diameter cam portion 28a contacts the stopper 37. Stop rising after touching. Therefore, by rotating the cam 28, the first
Of the lever L1 and the contact arm 26
Can be adjusted in stages.

FIGS. 5 and 6 show the change in the initial position of the second lever L2 depending on the rotational position of the cam 28. FIG. 5A shows the surface of the small-diameter cam portion 28b and the large-diameter cam portion 28a having the smallest lift amount. Faces upward, and the cam contact surface 34 of the second lever L2 is in contact with the upper surface of the small-diameter cam portion 28b.
The opening angle between the first lever L1 and the second lever L2 is 90
Degree. Hereinafter, when the cam 28 is rotated counterclockwise by one step in FIG.
(D) As shown in (e), the opening angle of the first lever L1 and the second lever L2 sequentially increases as shown in the figure.

Next, when the contact arm 26 is pressed and pushed against the object to be driven, the contact arm 26 corresponds to each of the cam rotation positions in FIGS. 5 (a), 5 (b), 5 (c), 6 (d) and 6 (e).
(A), (b), (c) and FIGS. 8 (d), (e), the upper surface of the large-diameter cam portion 28a abuts against the stopper 37 of the housing 2, and the contact arm 26 depends on the rotational position of the cam 28. Stops at five different elevation positions where the driving depth becomes shallower every 0.5 mm from the 0 mm position where the driving depth is deepest. At the same time, the push button of the contact detection switch 27 is pressed by the second lever L2, and a contact detection signal is input from the contact detection switch 27 to the control unit.

At this time, as described above, the opening angle of the first lever L1 and the second lever L2 differs depending on the rotation position of the cam 28, and the rotation stop position of the second lever L2 is fixed. Because it has been set, the second lever L2
The stroke of pressing the push button of the contact detection switch 27 is constant regardless of the rotational position of the cam 28. Therefore, an excessive load is applied to the push button of the contact detection switch 27 due to a change in the ascending and stopping position of the contact arm 26, and the push stroke is not short, and the contact detection signal is reliably output.

It should be noted that the present invention is not limited to the above-described embodiment, and various modifications are possible within the technical scope of the present invention, and it goes without saying that the present invention extends to those modifications. is there.

[0026]

As described above, in the contact arm of the electric nailing machine of the present invention, since the volume of the nose portion is reduced as much as possible by using the lever and the cam, the visibility of the driving position and the corner portion are reduced. It is easy to drive into. Also,
By rotating the cam, the driving depth can be easily and quickly adjusted, which can contribute to improvement of workability.

[Brief description of the drawings]

FIG. 1 is a side sectional view of an electric nailing machine according to an embodiment of the present invention.

FIG. 2 is a front sectional view of the electric nailing machine, showing the embodiment of the present invention.

FIG. 3 is a side sectional view of a contact arm portion.

FIG. 4 is an exploded perspective view of a contact arm portion.

FIGS. 5 (a), (b) and (c) are explanatory views showing changes in the initial position of a second lever L2 depending on the rotational position of a cam.

FIGS. 6 (d) and (e) are explanatory diagrams showing changes in the initial position of the second lever L2 depending on the rotational position of the cam.

FIGS. 7A, 7B, and 7C are explanatory diagrams showing a change in a stop position of a contact arm depending on a rotation position of a cam.

FIGS. 8 (d) and (e) are explanatory diagrams showing changes in the stop position of the contact arm depending on the rotational position of the cam.

[Description of Signs] 1 Electric nailing machine 2 Housing 3 Driver 6 Nose 9 Planetary gear device 10 Plunger lifting device 21 Plunger 26 Contact arm 27 Contact detection switch 28 Cam 28a Large diameter cam portion 28b Small diameter cam portion 28c Camshaft 29 Knob 31 Sleeve 32 Compression coil spring 36 Compression coil spring 37 Stopper L1 First lever L2 Second lever

Claims (2)

[Claims] 1. A nose portion of a nailing machine is provided with a contact arm slidable in a nail injection direction, and a tip end of the contact arm projects from a tip end of the nose portion in a nail injection direction via a spring. An electric nailer, wherein the other end of the contact arm is opposed to a push button of a contact detection switch in the nailer housing, and the contact detection switch is turned on and off by sliding operation of the contact arm. In the contact arm, a plate-shaped contact arm slidable in a nail injection direction is accommodated in a nose, an intermediate portion of a lever is pivotally mounted in the housing, and a front end of the lever is engaged with the contact arm. With the rear end of the lever facing the push button of the contact detection switch, the contact detection switch is turned on via the lever. And a cam is pivotally mounted on a side surface of the lever, a click stop mechanism is interposed on the cam, and a stopper is provided on the housing to regulate a range of elevation of the lever, and the housing is opposed to the cam, A contact arm of an electric nailing machine, wherein a rising limit of the contact arm is switched according to a rotation position of the cam. 2. A contact arm slidable in a nail injection direction at a nose portion of a nailing machine, and a tip end of the contact arm protrudes from a tip end of the nose portion in a nail injection direction via a spring. An electric nailer, wherein the other end of the contact arm is opposed to a push button of a contact detection switch in the nailer housing, and the contact detection switch is turned on and off by sliding operation of the contact arm. In the contact arm, a plate-like contact arm slidable in the nail ejection direction is accommodated in a nose, and a first lever and a second lever are coaxially pivotally mounted in the housing. A front end is engaged with the contact arm, and a rear end of the second lever is opposed to a push button of the contact detection switch. A stopper is provided for pivotally connecting a cam to the cam, interposing a click stop mechanism on the cam, pressing a second lever against the cam by a spring, and restricting a rising range of the first and second levers to the housing. And the upper limit of the contact arm and the relative angle between the first lever and the second lever can be freely switched according to the rotation position of the cam, and the contact angle can be changed regardless of the rotation position of the cam. A contact arm for an electric nailing machine, wherein the rotational position of the rear end of the second lever at the upper limit of the arm is constant.