JP3070708B2 - Continuous screw tightening machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuous screw tightening machine for continuously feeding and screwing each screw attached to a screw connection band.

[0002]

2. Description of the Related Art Generally, a continuous screw tightening machine of this type includes a main body having a built-in drive motor, a driver bit drive shaft protruding from the main body and rotated by the drive motor, and attached to the main body. A case having a longitudinal direction in the axial direction of the driver bit driving shaft, a moving member slidably mounted in the case in the longitudinal direction of the case, and a screw provided at the moving member and having an end screwed in. A contact member that is pressed against the object to be tightened, and a spring that biases the moving member in a direction in which the contact member protrudes from the distal end of the case. And a screw supply device for sequentially feeding each screw of the screw connection band to a screw tightening position by a driver bit attached to a driver bit drive shaft.

By the way, such a continuous screw tightening machine is provided with a screw-in depth adjusting device for regulating a limit of movement of a contact member in a direction opposite to a projecting direction in order to adjust a screw-in depth. As such a screw-in depth adjusting device, as shown in Japanese Utility Model Laid-Open Publication No. 62-12779 and Japanese Utility Model Publication No. 62-92165, a nut is screwed into an outer peripheral portion of a connecting portion between a case and a main body. A configuration in which the vertical position of the lever nut is variable and a pin that can abut on the lower surface of the nut on the upper side of the moving member, or screwed into the upper part of the case as shown in U.S. Pat.No. 4,059,0343. There has been proposed a configuration in which a pin capable of contacting a moving member is protruded from a lower surface of a nut to be moved.

In a continuous screw tightening machine of this type, the length of a screw which is provided at an end of a moving member and which applies the height of a contact member pressed against an object to be screwed into which a screw is to be screwed is applied. In order to enable a tightening operation in accordance with the screw length by changing the contact length, a configuration has been proposed in which the contact member is attached to the moving member so that the height can be adjusted.

[0005] However, when a structure for adjusting the height of the abutting member is adopted in the configuration of the conventional continuous screw tightening machine, the moving distance of the moving member in the direction opposite to the projecting direction of the moving member set by the nut is limited. Since it is invariant regardless of the height of the contact member, the rotation of the nut must be largely adjusted each time the length of the screw to be applied changes, which has a disadvantage of poor operability. Further, since the nut for adjusting the screwing depth is screwed onto the outer periphery of the connection portion between the case and the main body, there is a disadvantage that the case and the main body are elongated by the amount of the nut and the screw with which the nut is screwed. Was.

[0006] For this reason, the same applicant as the present application has filed Japanese Patent Application No.
-80980, a body having a built-in drive motor, a driver bit drive shaft protruding from the body and being rotationally driven by the drive motor, and a case attached to the body and having a longitudinal direction in the axial direction of the driver bit drive shaft. And a moving member slidably mounted in the case in the longitudinal direction of the case, and a positionally attached to the moving member according to the length of a screw to be applied, the end of which should screw in the screw. A contact member pressed against the clamped body, a spring for urging the moving member in a direction in which the contact member protrudes from the distal end of the case, and a spring provided on the moving member and related to the movement of the moving member. A screw feeder for sequentially feeding each screw of the screw connection band to a screw tightening position by a driver bit attached to a driver bit drive shaft. In, the case side along with the rotation of the operation knob, proposes a contact height providing variable threaded rods or polygonal cam plate configuration for a stopper portion provided in the contact member.

In the continuous screw tightening machine having such a configuration, if the contact height of the contact member of the screw rod or the polygonal cam plate with respect to the stopper portion is changed by turning the operation knob, the moving stroke of the moving member is also reduced. Change accordingly,
The shorter the distance between the moving member and the abutting member, the shorter the moving stroke, so that the screwing depth can always be kept constant regardless of the length of the screw to be applied, and the above-mentioned disadvantages of the prior art can be overcome. Things.

[0008]

However, in the locking mechanism using the screw rod of the continuous screw tightening machine disclosed in Japanese Patent Application No. 3-80980, a nut member screwed to the screw rod, There is a problem that the structure becomes complicated, for example, it is necessary to provide a mechanism for preventing co-rotation with the nut member. In the locking mechanism using the polygon cam, adjustment of the contact height is required. However, since it can be performed only at a number of height positions corresponding to the number of corners of the polygon cam, further improvement has been desired.

[0009]

In order to solve the above-mentioned problems, a continuous screw tightening machine according to the present invention comprises a main body having a built-in drive motor, and a driver bit protruding from the main body and rotated by the drive motor. A drive shaft, a case attached to the main body and having a longitudinal direction in the axial direction of the driver bit drive shaft, a moving member slidably mounted in the case in the longitudinal direction of the case, and a screw to be applied. A contact member that is attached to the moving member so as to be adjustable in accordance with the length of the moving member, and whose end is pressed against a body to be screwed into which a screw is to be screwed; A spring for urging in a direction protruding from the distal end, and a screw provided on the moving member, wherein each screw of a screw connection band is attached to the driver bit drive shaft in relation to the movement of the moving member. A screw supply device that sequentially feeds the screw to a screw tightening position by a driver bit, wherein between the case and the abutting member, a direction in which the abutting member protrudes from the case. A locking mechanism for restricting the movement limit in the opposite direction is provided, and at least one of the locking portion on the case side and the locking portion on the contact member side of the locking mechanism is locked by the operation of an operator. The cam plate is provided with a curved locking surface whose contact height with respect to the portion is variable.

[0010]

In the continuous screw tightening machine according to the present invention, the screwing depth is regulated by the locking mechanism between the case and the abutting member, and the abutting surface of the cam plate abuts against the other engaging portion. If the position is changed continuously, the moving stroke of the moving member also changes continuously accordingly, and the shorter the distance between the moving member and the contact member, the shorter the moving stroke. Therefore, regardless of the length of the screw to be applied, the screwing depth can always be kept constant, and the screwing depth is regulated by the curved locking surface of the cam plate. Can be finely set to many values.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be specifically described below with reference to the drawings. A continuous screw tightening machine shown in a partial longitudinal sectional view in FIG. 1 has a hollow main body 10 that can be divided into two parts in a left-right direction (a direction perpendicular to the paper surface), and a motor 12 has an armature inside the main body 10. The shaft 14 is arranged so as to be inclined at about 45 ° with respect to the vertical direction (the longitudinal direction of a case 56 described later). In addition, a grip 10a by an operator is provided on the upper part of the main body 10, and this grip 1
A space 16 for inserting an operator's hand is formed in a lower portion of Oa between the housing portion of the motor 12. In addition, a trigger switch 17 that can be operated by a finger of an operator in a gripping state of the gripping portion 10a for starting the motor 12 is disposed on a lower surface of the gripping portion 10a.

Inside the main body 10, a first gear shaft 22 whose both ends are supported via bearings 18 and 20 is vertically arranged at a position close to a lower portion of the armature shaft 14 of the motor 12. . This first gear shaft 22
A bevel gear 24 fixed to the armature shaft 14
The bevel gear 26 that meshes with the shaft is fixed, and these shaft angles form 45 °.

Further, a driver bit drive shaft 28 is vertically arranged below the main body 10 so as to partially protrude from the lower surface of the main body 10 adjacent to the first gear shaft 22. It is slidably and rotatably supported in the axial direction via an oilless bearing 30. The driver bit drive shaft 28 has an upper end portion 28 a formed in an enlarged diameter shape, and is engaged with an upper end of an oilless bearing 30.
8b. Above the driver bit drive shaft 28, a second gear shaft 32 is disposed coaxially therewith. The upper end of the second gear shaft 32 is rotatably supported on the main body 10 via a bearing 34, and the lower end is inserted into a bottomed shaft hole 36 formed on the upper portion of the driver bit drive shaft 28, It is rotatable with respect to a steel ball 38 arranged in the shaft hole 36.

A small gear 40 is fixed to the first gear shaft 22 above the bevel gear 26, and a large gear 42 meshing with the small gear 40 is rotatably and axially movable to the second gear shaft 32. Mated. A pair of cam surfaces 4 formed on the outer periphery of the second gear shaft 32 are provided inside the large gear 42.
An annular groove 48 is formed for accommodating a pair of steel balls 46 (only one is shown in the figure) cooperating with each other. Here, each cam surface 44 is formed by gradually changing the depth (vertical depth) of the cam groove formed thereby in the circumferential direction.

On the lower surface of the large gear 42 and the upper surface of the enlarged upper end 28a of the driver bit drive shaft 28 facing the large gear 42, clutch teeth 50 and 52 that can mesh with each other are formed. Here, a compression coil spring 54 is interposed between the large gear 42 and the upper end 28 a of the driver bit drive shaft 28, and the large gear 42 normally supports the upper end of the second gear shaft 32 as illustrated. The driver bit 28 abuts against the lower surface of the bearing 34, while the driver bit 28 holds the upper end 28a of the upper end 28a of the oilless bearing 30 so as to keep the clutch teeth 50 and 52 in the non-meshing position.

In the above configuration, when the motor 12 is started by operating the trigger switch 17, the rotation of the armature shaft 14 is transmitted to the first gear shaft 22 via the bevel gears 24 and 26, and further transmitted through the small gear 40. From the gear 42, a cam surface 44 and a steel ball 46
Is transmitted to the second gear shaft 32 via a cam mechanism composed of the following. However, the clutch teeth 50 of the large gear 42 and the clutch teeth 52 of the driver bit drive shaft 28 are not engaged with each other, and the second gear shaft 32 I do. From this state, an upward pressing force is applied to the driver bit drive shaft 28, and the second gear shaft 3
When an axial load is applied to the second gear shaft 32 via the steel ball 38, the torque transmitted to the second gear shaft 32 via the cam mechanism increases, whereby the engagement of the steel ball 46 with the corresponding cam surface 44 in the cam mechanism is increased. The engagement position shifts to the shallow portion of the cam groove formed by the cam surface 44 with the relative rotation of the large gear 42 with respect to the second gear shaft 32, and the large gear 42 is moved downward along the second gear shaft 32. Move to As a result, the clutch teeth 50 of the large gear 42 mesh with the clutch teeth 52 of the driver bit drive shaft 28, and the large gear 4
2 rotates the driver bit 29 further from the driver bit drive shaft 28. The above-described pressing force on the driver bit drive shaft 28 is generated when the driver bit 29 is pressed against a work for a screw tightening operation described below. When the load applied to the bit drive shaft 28 decreases, the large gear 42 moves upward by the urging force of the compression coil spring 54, and the engagement between the clutch teeth 50 and 52 is released.

On the lower surface of the main body 10 from which the driver bit drive shaft 28 protrudes, a case 56 having a hollow rectangular cross section with open upper and lower ends is mounted so as to surround the driver bit drive shaft 28 together with the oilless bearing 30. I have. A moving member 58 is mounted inside the case 56 so as to be vertically slidable. The moving member 58 is constantly urged downward by a compression coil spring 60.

As shown in FIG. 2, a vertically long hole 62 is formed in a left side plate 56a of the case 56 (a side plate on the near side in FIG. 1). The moving member 5 is inserted into the elongated hole 62.
The head of the bolt 64 screwed into the corresponding side surface of the movable member 8 protrudes, and the range of vertical movement of the moving member 58 is restricted to the range of the length of the elongated hole 62. As described above, the moving member 58 is always urged downward by the compression coil spring 60, and the head of the bolt 64 is normally locked to the lower end of the elongated hole 62 as shown in FIG. Held at the lowest position. The guide mechanism by the engagement between the elongated hole 62 and the head of the bolt 64 is similarly provided on the other side plate 56c facing the side plate 56a.

As shown in FIG. 3, the moving member 58 has bifurcated legs 66 and 68, and a screw connecting band B (see FIG. A shaft 71 of a ratchet wheel 70 for sequentially feeding the moving member 58 with the vertical movement of the moving member 58 is pivotally supported. The ratchet wheel 70 has a plurality of claws 72 at an equal pitch on the outer periphery.
1, and a pair of left and right ratchet wheels 74, 74 each having a corresponding one of the ratchet wheels 70, 74 on the corresponding side of the ratchet wheel 70, as shown in FIG. A guide surface 76 for guiding both side portions of the screw connection band B;
76 are formed. Here, a plurality of grooves (not shown) with which the claws 72 to 72 of the ratchet wheels 74, 74 on each side are engaged are formed at both sides of the screw connection band B at the same pitch. The pitch of the claws 72 to 72 is set to be equal to the pitch of the groove of the screw connection band B, and the screw connection band B is sequentially along the guide surfaces 76, 76 with the rotation of the ratchet wheel 70 in the direction of the arrow in FIG. It is movable.

A roller pin 78 protrudes from the outer peripheral portion of the side surface of the ratchet wheel 70 via ratchet means (not shown). As shown in FIG. 2, the roller pin 78 is inserted into a curved long hole 80 formed in the leg 68 on the corresponding side of the moving member 58 and a substantially L-shaped long hole 82 formed in the side plate 56 a of the case 56. I'm rushing. A stopper 84 for locking the pawls 72 to 72 is pivotally supported via a pin 86 on a side of the ratchet wheel 70 adjacent to an upper portion of the one ratchet wheel 74. It is always urged in the direction of engagement with the claw 72 by a leaf spring 88 supported in a cantilever manner above.

The elongated hole 82 has a first portion 82a extending in the vertical direction, that is, the longitudinal direction of the case 56, and the first portion 82a.
and a second portion 82b that extends obliquely downward from the lower portion of a. When the moving member 58 is located at the lower limit thereof, the roller pin 78 moves to the elongated hole 80 of the moving member 58.
Of the long hole 82 of the case 56 and the second portion 82b of the long hole 82 of the case 56
And the second moving member 58 moves upward against the urging force of the compression coil spring 60,
The inside of the elongated hole 80 is guided from the one end to the other end by being guided by the portion 82b, and reaches the other end of the elongated hole 80 when reaching the first portion 82a. Thereby, the ratchet wheel 70 rotates in the direction of the arrow in FIG. 1 by the angle corresponding to the angular interval between the adjacent claws 72 to 72 of the ratchet 74 via the ratchet means, and the stopper 84 rides over the next pawl 72. It reaches the opposite side of the rotation direction. Next, when the moving member 58 moves down and the roller pin 78 moves downward along the second portion 82b of the elongated hole 82, the ratchet wheel 70 is prevented from rotating in the reverse direction by the stopper 84, so that one of the claws 72 It is kept rotated by the pitch.

Accordingly, the screw connection band B is fed by one pitch of the screw S as the moving member 58 moves up and down.

The legs 66, 68 of the moving member 58
An L-shaped contact member 90 that contacts the work W whose lower surface is screwed is attached to the lower end of the screw. The contact member 90 has a structure in which two L-shaped contact pieces 90a and 90b are joined to each other at an end of a horizontal portion.
A groove 92 is formed between the contact pieces 90a and 90b to allow the screw S to be inserted. Elongated holes 94 are formed in the contact pieces 90a and 90b in the vertical direction, respectively.
6 and 68 are fixed by screws 96 via these elongated holes 94, respectively. The height at which the contact member 90 is attached to the moving member 58 is variable by changing the engagement position of each screw 96 with the elongated hole 94 according to the length of the screw S of the screw connection band B to be applied. Pins 100 and 102 are projected above a screw hole 98 into which the screw 96 of each leg 66 and 68 is screwed.
a, a first position where the upper end of 90b abuts on the pin 100;
The second position where the upper ends of the contact pieces 90a and 90b abut on the lower end of the pin 102, and the upper ends of the contact pieces 90a and 90b are
Positioning is possible at a third position abutting on the lower surface of the step portion 104 formed on each of the steps 6 and 68.
The first position, the second position, and the third position correspond to the case where the length of the screw S is 40 mm, 32 mm, and 25 mm, respectively.

Here, between the case 56 and the contact member 90, a locking mechanism for adjusting the screwing depth of the screw S is provided by restricting the upper limit of the contact member 90 with respect to the case 56. The configuration of this locking mechanism will be described below.

As shown in FIG. 3, a substantially inverted L-shaped stopper piece 108 having an upper end 108a bent substantially horizontally is formed integrally with the contact piece 90a of the contact member 90 as shown in FIG. I have. On the other hand, the upper end portion 108 of the stopper piece 108
An arc-shaped cam plate 110 shown in a side view in FIG. The cam plate 110 is integrally provided with a cam shaft 114 rotatably supported via a bush 112 on a rear side plate 56b of the case 56, and the cam shaft 114 is opposite to the arc-shaped cam plate 110. Is attached to the side plate 5 of the case 56.
An adjustment knob 116 is attached to the outer surface of 6b in a sliding state.

As shown in FIG. 4, the cam plate 110 has a curved cam surface 110a and a straight cam surface 110b, and the curved cam surface 110a is a distance from the center O of the cam shaft 114. Are gradually and continuously increased from the minimum distance R1 at the start point A of the cam surface 110a to the maximum distance R2 at the end point T. Accordingly, with the rotation of the adjustment knob 116, the contact height of the stopper member 108 with respect to the cam surface 110a of the contact member 90 changes continuously, and the ascending limit of the contact member 90 and, consequently, the moving member 5
The rising limit of 8 is continuously variable.

The position of the adjusting knob 116 in the axial direction is regulated by a circlip 118 fitted to a small diameter portion at the end of the cam shaft 114. The other end of the cam shaft 114 is formed with a chamfered portion 120 at a portion opposed in the diameter direction, and an inner peripheral surface of an adjustment knob 116 fitted to this portion is also formed in a corresponding shape. Of the cam shaft 114 is stopped. A washer 1 is provided between the circlip 118 and the adjustment knob 116.
22 are interposed.

As shown in FIGS. 3 and 5, a serration 124 is formed on the outer periphery of the adjusting knob 116 in an appropriate range in the circumferential direction. As shown in FIG.
The lower portion of the body 10 located above the adjustment knob 116 has a groove 130 having a substantially T-shaped cross section for receiving a stopper 128 having teeth 126, 126 engaging with the serration 124.
Are formed. A stopper 128 is provided in the groove 130.
A compression spring 132 for constantly biasing the lower portion is disposed, and a stopper 128 is provided with an enlarged portion 128a provided on the upper portion thereof with its teeth 126, 126 engaged with the serration 124 as shown in the figure. Are set so as to be locked to the step 130a of the groove 130.

As described above, the adjustment knob 116 can be positioned at any rotational position within the range of the serration 124 by the engagement between the serration 124 and the teeth 126, 126. The ascending limit of the moving member 58 via the member 90, that is, the screwing depth can be arbitrarily set.

Next, the operation of the above embodiment will be described.
First, the operator grips the grip 10a of the main body 10 and
6. Put your finger on 6 and operate the trigger switch 17 to
Start 2 In this state, as described above, the driver bit drive shaft 28 does not rotate, and the second gear shaft 32 idles.

Next, the contact member 9 is held while the main body 10 is held.
0 is pressed against the upper surface of the workpiece W, the moving member 58 moves upward in the case 56 against the spring 60.
That is, it enters the case 56. Ratchet wheel 7 0 with the movement of such movable member 58 is rotated in FIG. 1 in the direction of the arrow, it is moved by the amount corresponding the screw strip B to 1 pitch of the screw S. Accordingly, the next screw S adjacent to the screw S located below the driver bit 29 is moved to a position below the driver bit 29. (After the screw connection band B is moved in this manner, its position is maintained until the moving member 58 is pushed upward again, as described above.)

After the screw connection band B moves, the moving member 58
Further into the case 56, the driver bit 29 comes into contact with and engages with a screw S located thereunder, and the screw S
Is disengaged downward from the screw connection band B, and the tip end thereof is brought into contact with the work W. Exposing further pushed toward the driver bit 29 on the work W, joined by a pressing force upward to the driver bit drive shaft 2 8, as described above, the cam between the large gear 42 and the second gear shaft 32 By the operation of the mechanism, the rotation of the large gear 42 is transmitted to the driver bit drive shaft 28 through the engagement of the clutch teeth 50 and 52, and the rotation is given to the screw S and screwed into the work W.

The moving member 58 further moves up in the case 56, and the stopper piece 108 of the contact member 90 is
When it comes into contact with 0, the moving member 58 is further prevented from ascending, and the screw S is screwed into the work W to a predetermined depth as shown in FIG.

When the pressing of the main body 10 through the grip 10a is released after the screw S has been screwed in, the clutch teeth 50 are disengaged from the clutch teeth 52 as described above, and the second gear shaft 32 is re-engaged. Idling and moving member 58
Is returned to the original position by the restoring force of the spring 60, and one cycle of the screwing operation is completed.

Here, the mounting height of the contact member 90 with respect to the moving member 58 is the first position, the second position corresponding to the case where the length of the screw S of the screw connecting band B to be applied is 40 mm, 32 mm and 25 mm, respectively. The distance between the lower surface of the contact member 90 that contacts the work W and the lower end of the screw S at each of these positions is set in the same manner. The operation from the release from the contact to the contact with the work W is always performed in a constant state.

The rising stroke of the moving member 58 is regulated by the contact between the stopper piece 108 of the contact member 90 and the cam surface 110a of the cam plate 110. This rising stroke is controlled by the moving member of the contact member 90. The shorter the length of the screw S becomes, the shorter the length of the screw S becomes in accordance with the above-described mounting height with respect to the screw 58. For this reason, the adjusting knob 116 is turned to reduce the screw-in depth of the screw S by the driver bit 29 by one.
If the type of screw S is set as desired, a constant screwing depth can always be obtained even when the length of the screw S used is different, and the cam plate 110 has a curved shape that changes continuously. Since the cam surface 110a is provided, the screwing depth can be set to many values and finely.

In connection with the above-mentioned screw tightening operation, in the present embodiment, the motor 12 is
0 is disposed obliquely at the lower part close to the upper gripping part 10a.
2, the moment applied to the grip portion 10a is reduced, and the operability is improved.

Next, a second embodiment of the present invention will be described with reference to FIGS. This embodiment is the same as the first embodiment except for a mechanism for positioning the rotational position of the cam plate 110, and the same members as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted. I do.

At the end of the cam shaft 114 opposite to the cam plate 110, an adjustment knob 116A is provided with a side plate 56b of the case 56.
Is mounted on the outer surface of the device such that its central portion is in sliding contact.
The inner peripheral surface of the fitting portion of the adjustment knob 116A with the camshaft 114 is formed in a shape corresponding to the chamfered portions 120, 120 of the camshaft 114, and is detented as in the above embodiment. A circlip 1 is provided at the small diameter portion at the end of the cam shaft 114.
A spring washer 122A is interposed between the circlip 118A and the adjustment knob 116A, and the adjustment knob 116A is attached to the side plate 56 of the case 56.
It is always urged toward the b side.

The side plate 5 of the case 56 of the adjustment knob 116A
As shown in FIGS. 7 and 8, on the outer peripheral portion of the surface on the 6b side,
Grooves 134 to 134 having a substantially V-shaped cross section are formed in the radial direction at equal intervals in the circumferential direction. On the other hand, the side plate 56 of the case 56
b at the portion facing the outer periphery of the adjustment knob 116A,
The pin 136 is penetrated and fixed with its head 136a positioned on the outer surface side of the side plate 56b.
As shown in FIG. 8 , a is fitted into one of the grooves 134 to 134 to position the adjustment knob 116A.

That is, the adjusting knob 116A is
When one of the pins 34 to 134 is rotated from a state fitted to the head 136a of the pin 136, the adjustment knob 11 is rotated.
6A is a camshaft 1 that resists the urging force of the spring washer 122A.
The adjacent grooves 13 are sequentially repeated by moving and restoring along the grooves 14.
4 to 134 are sequentially fitted to the head 136a, and the adjusting knob 1
16A can be positioned at a desired rotation position.
Also, as shown in FIG. 7 , a projection 137 is provided on the outer peripheral portion of the adjusting knob 116A at an appropriate angle range on the outer peripheral portion. Both ends of the projection 137 in the circumferential direction are provided with adjustment knobs 11.
As shown in FIG. 6 when 6A rotation of the side plates of the cases 5 6 5
6b abuts on the side protrusion 139 provided at the upper end,
It is to regulate the rotation range of the adjustment knob 116 A.

The operation of the second embodiment is the same as that of the first embodiment, except that a mechanism for positioning the rotation position of the adjustment knob 116A, that is, the pin 136, is provided not on the main body 10 but on the case 56. Since there is no need to consider the positional relationship between the main body 10 and the case 56 in relation to such a positioning mechanism, high-precision assembly is not required, and the mounting of the case 56 to the main body 10 is not required. By changing the direction of the adjustment knob 116A
Can be located on any of the front, rear, left and right sides.

Next, a third embodiment of the present invention will be described with reference to FIG. This embodiment is a modification of the second embodiment described above, and is the same except for the adjustment knob 116A and its related structure. Therefore, only the main part is shown and other parts are not shown. The same members as those in the embodiment are denoted by the same reference numerals, and description thereof will be omitted.

The cam shaft 114B of the present embodiment is formed integrally with the cam plate 110 is directly rotatably supported to the side plate 56 b of the case 56, the dish Ne <br/> di 142 relative adjustment knob 116B Mounted directly through. That is,
The cam shaft 114B shank countersunk screws 14 2 are formed screw holes 140 for screwing, the head 142a of the countersunk screw 142 in the central portion of the adjusting knob 116B is fitted, the hole of a corresponding conical shape 14 4 are formed. Adjustment knob 1
A side plate 5 is provided at a central portion having a 16B conical hole 144.
On the side facing the 6 b, a boss portion 143 which the front end portion of the cam shaft 114B is fitted are formed integrally, in a mounted state shown, the cam plate 110 and the boss portion 14
3 is set to be sliding contact on the surface of the corresponding side of the side plate 56 b.

Also, on the outer periphery of the adjustment knob 116B,
As in the above embodiment, the grooves 134 to 1 into which the pins 136 fit are provided.
34. An intermediate portion 145 between the outer peripheral portion and the boss portion 143 is formed in a thin shape.
The pin 136 is elastically bent outward when the pin 136 gets over the adjacent grooves 134 by the rotation of the adjustment knob 116B, and is restored when the next groove 134 reaches the position of the pin 136. 136 is kept in a fitted state with the head 136a .

[0046] Note that the side plate 56 b of the case 56 and projection 146 to the outside is provided in a portion facing the intermediate portion 145 of the adjustment knob 116B, the projection 14
Numeral 6 cooperates with a corresponding projection provided on the adjustment knob 116B to regulate the rotation range of the adjustment knob 116B.

The effect of this embodiment is the same as that of the second embodiment, except that the adjusting knob 116B is directly fixed to the camshaft 114B and the adjusting knob 116B itself has elasticity, so that the adjusting knob 116B itself has an advantage. There is an advantage that members are not required, the number of parts can be reduced, and the structure is simple. In the above embodiment, the contact portion
Movement of the material 90 with respect to the case 56 in the direction opposite to the projecting direction
Rotates with respect to case 56 as a locking mechanism that regulates the source
A cam plate 110 is provided via a possible cam shaft 114,
Is a locking portion on the case side, while the contact member 90 is
The upper piece 108 is provided, and this is used as a locking portion on the contact member side.
However, if the cam plate 110 is only used as a locking part on the case side,
It can also be used as a locking part on the contact member side,
Of the locking parts on the case side or locking parts on the contact member side,
At least one of the cam plates 110 may be provided.

[0048]

According to the continuous screw tightening machine of the present invention, the screwing depth is regulated by the locking mechanism between the case and the abutting member. The screwing depth is regulated by the curved locking surface of the cam plate, and the screwing depth can be set to many values, improving operability. Has advantages.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a continuous screw tightening machine according to a first embodiment of the present invention.

FIG. 2 is a front view showing the case shown in FIG. 1 together with a moving member.

FIG. 3 is a side view showing the case and the moving member shown in FIG. 1 together with a part of a main body.

FIG. 4 is a side view of the cam plate shown in FIG.

FIG. 5 is a side view similar to FIG. 3, showing a state in which screw tightening is completed.

FIG. 6 is a longitudinal sectional view of a main part of a continuous screw tightening machine according to a second embodiment of the present invention.

FIG. 7 is a view of the adjusting knob shown in FIG. 6 as viewed from the back side.

8 is a side view of a case with respect to a groove of an adjustment knob shown in FIG. 7;
It is an expanded sectional view which shows the engagement state of the head of the pin of a board .

FIG. 9 is an enlarged sectional view of a main part showing a third embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Main body 12 Motor 28 Driver bit drive shaft 29 Driver bit 56 Case 58 Moving member 60 Compression coil spring 72-72 Claw 70 Ratchet wheel 90 Contact member 108 Stopper piece 110 Cam plate 110a Cam surface 116, 116A, 116B Adjustment knob B Screw Connecting band S Screw

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B25B 21/00 B25B 23/04

Claims (1)

(57) [Claims] 1. A main body having a built-in drive motor, a driver bit drive shaft protruding from the main body and driven to rotate by the drive motor, and a longitudinal direction attached to the main body and extending in the axial direction of the driver bit drive shaft. A case having, and a moving member slidably mounted in the case in the longitudinal direction of the case, and a positionally attached to the moving member according to a length of a screw to be applied,
An abutting member whose end is pressed against a body to be screwed into which a screw is to be screwed; a spring for urging the moving member in a direction in which the abutting member protrudes from a distal end portion of the case; and a moving member. And a screw supply device for sequentially feeding each screw of the screw connection band to a screw tightening position by a driver bit attached to the driver bit drive shaft in relation to the movement of the moving member. hand,
A locking mechanism is provided between the case and the abutting member to limit a movement limit of the abutting member in a direction opposite to a direction in which the abutting member protrudes from the case, and a locking portion on the case side of the locking mechanism or At least one of the engaging portions on the contact member side is provided with a cam plate having a curved engaging surface whose contact height with respect to the other engaging portion is variable by an operation of an operator. Features a continuous screw tightening machine.