JPS624575A - Electric driver - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field of the Invention) The present invention relates to an improvement in an electric screwdriver that automatically tightens screws and adjusts the position of parts of electronic equipment.

[Technical background of the invention]

In recent years, it has been used to tighten guide bins and position setting screws for videotape running systems, for example. A device has been developed that automatically performs one adjustment operation while reproducing a videotape in response to a reproduction signal. In this type of device, electric screwdrivers each having a bit are arranged corresponding to the position of the bottle or screw to be adjusted, and adjustment is performed by rotating each of these electric screwdrivers. FIG. 6 shows an example of the configuration of the electric screwdriver. In the same figure, 10
is a circular tubular transmission shaft which is rotated by the driving force of a motor (not shown), and this transmission shaft 10 is rotatably fixed and held by a bearing 21 in a fixing hole provided in a base 20.

Note that 22 and 23 are nuts for keeping the transmission shaft 10 in a fixed state. A moving shaft 30Ifi is inserted into the hollow part of the transmission shaft 10 so as to be movable in the vertical direction A-A', and this moving shaft 30 is always moved in the distal direction A by a compression spring 32 provided in the hollow part of the transmission shaft 10. is energized by The biasing force provided by the compression spring 32 is for pressing a bit 40, which will be described later, against a screw 60, which is a rotated component.

The movement range of the moving shaft 30 is defined as a range in which the bin 33 of the moving shaft 30 can move within the long window 11 provided in the transmission shaft 10.

On the other hand, a bit 40 is inserted into the tip of the hollow portion of the transmission shaft 10. A recess 41 is formed on the peripheral surface of the base end of the bit 40, and by engaging the steel ball 12 with the four parts 41 using an adapter 50, the bit 40 is held so as not to fall off the transmission shaft 10. be done. The adapter 50 is always pushed downward by a compression spring 51 provided between the adapter 50 and the retaining ring 52, so that the bit 40 is maintained in the inserted state. Also, the above bit 40
A pin 42 is protruded from the circumferential surface of the middle circumferential portion of the bit 40, and by engaging the pin 42 with the groove 13 of the transmission shaft 10, the bit 40 rotates integrally with the transmission shaft 10.

Therefore, when tightening or loosening the screw 60 using an electric screwdriver with such a configuration, first align the screw 60 and then lower the electric screwdriver together with the base 20 to tighten the bit 40. The tip portion is seated on the rotation stopper of the screw 60. In this state, a motor (not shown) is driven to rotate the bit 40, thereby tightening or loosening the screw 60. Therefore, by using a device equipped with such an electric screwdriver, it is possible to automatically perform everything from setting the bit to the screw 60 to tightening or loosening it, which saves work compared to when the operator manually adjusts the screw 60. Efficiency can be greatly increased.

(Problems with the Background Art) However, although this type of conventional adjustment device does have the function of positioning the bit 40 with respect to the screw head, this function alone does not always ensure that the bit 40 is properly positioned to prevent the screw head from rotating. In other words, if the direction of the rotation stopper of the screw head and the direction of the bit 40 are different, when the bit 40 is lowered, the bit 4o will be seated at the ma of the screw head.
It only contacts n and is not seated on the rotation stopper of the screw 6o. In this situation, bit 40
Even if the screw 60 is rotated, the screw 60 does not rotate at all, and as a result, adjustment cannot be made.Also, if the bit 40 suddenly engages with the detent of the screw 60 during rotation, the detent of the screw 60 or the bit 4o may be damaged, which was very unfavorable.

In addition, in order to avoid the above-mentioned situation, it is necessary for the operator to visually check whether the bit is securely seated on the rotation stopper of the screw 60 before rotating the bit, which saves the operator's time and effort. was increasing, leading to a decrease in adjustment efficiency.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide an electric screwdriver that can easily and reliably detect the seated state of a bit on a rotated component, thereby allowing reliable and efficient adjustment.

[Summary of the invention]

In order to achieve the above-mentioned object, the present invention arranges a position detector to face the side surface of a bit inserted into the tip of a hollow part of a transmission shaft or a member that moves in the axial direction integrally with the bit, This position detector detects the axial position of the bit or member, and the seating state of the bit relative to the rotated component is determined from the detection result.

[Embodiments of the invention]

FIG. 1 shows the configuration of an electric screwdriver according to an embodiment of the present invention. In this figure, the same parts as in FIG. 6 are given the same reference numerals and detailed explanations will be omitted.

A pair of pillars 72.75 are erected on the base 20, and a light emitting optical system 71 as a position detector and a light emitting optical system 71 as a position detector are mounted on these pillars 72.75 so as to face each other through the long window 11 of the transmission shaft 10. A light receiving optical system 76 is installed. The light emitting optical system 71 and the light receiving optical system 76 respectively project detection light guided from the light emitting unit 74 via the optical fiber 73 into the long window 11, and also project the detection light that has passed through the long window 11. The light is focused and sent to a light receiving section 78 via an optical fiber 77, where the light receiving section 78 converts it into an electrical signal. Furthermore, the positions of the light emitting optical system 71 and the light receiving optical system 76 are such that they face the upper end of the moving shaft 30 when the bit 40 is seated on the rotation stopper 61 of the screw 60 as shown in FIG. 2(a). On the other hand, bit 40 is shown in Fig. 2 (
As shown in b), the light is shielded by the upper end of the moving shaft 30 when the screw 60 is not seated on the detent 61. That is, the positions of the light emitting optical system 71 and the light receiving optical system 76 are set so that the step H caused by whether or not the bit 40 is seated can be determined.

On the other hand, a detection disk 80 is fitted on the circumferential surface of the transmission shaft 10, and phase detectors 81 and 82 are arranged on the curved surface of the detection disk 80 with the detection disk 80 sandwiched therebetween. There is. These phase detectors 81 and 82 are arranged at a distance of θ from each other as shown in FIG.
0, the pulse signal TS1. Generate TS2. In addition, the above-mentioned detection disk 8
The position of the 0 notch 84 is initially set to match the orientation of the bit 40 as shown in FIG.

In addition, the angle θ of each phase detection 1181.82 is as follows:
It is set to 90@ or a slightly larger value.

By the way, the electric screwdriver of this example is 113111 part 9.
0. This control section 90 has, for example, a microcomputer as a main control section, and has, as its functions, seating detection means 90a, detection timing designation means 90b, and seating setting control means 90c as shown in FIG. . The seating detection means 90a drives the light emitting section 74 to generate detection light, and determines whether or not the detection light passes between the light emitting optical system 7113 and the light receiving optical system 76, that is, bit 4.
0 is detected from the light reception signal of the light receiving section 78.

The detection timing specifying means 90b
The seating detection means 90a is caused to detect the seating at the time when the pulse signal TSI is generated from the timing. The reason why the detection timing specifying means 90b is provided is that the seating detecting means 90a performs detection through the long window 11 of the transmission shaft 10, so the light emitting optical system 71
This is because the seating state can only be detected when the light receiving optical system 76 faces the long window 11. The seating setting control means 90C is the seating detection means 90at'lt.
When it is detected that the person is not sitting, the motor drive circuit 91
is driven to rotate the transmission shaft 10 by 90 degrees, thereby seating the bit 40 on the stopper 61 of the screw 60. At this time, the rotation I (90°) of the transmission shaft 10 is:
It is set by monitoring the pulse signal TS2 generated from the phase detector 82.

Next, the operation of the electric screwdriver configured as above will be explained. When the bit 40 is lowered to the head of the screw 60 and this fact is transmitted from the adjustment section 1II (not shown), the control section 9
0 first drives the light emitting unit 74 to generate detection light, and in this state detects the presence or absence of the pulse signal TS1 from the phase detector 181. If the pulse signal TSI is generated, the light emitting optical system 71 and the light receiving optical system The system 76 is the long window 11 of the transmission shaft 10
It is determined that the passenger is facing the passenger, and the light receiving signal from the light receiving section 78 is taken in to determine whether or not the passenger is seated. For example, if the bit 40 is seated on the detent 61 of the screw 60,
The moving axis 30 is in a lowered state as shown by the solid line in FIG. 1, and the detection light of the light emitting optical system 71 is guided to the light receiving section 78 via the light receiving optical system 76, so the control section 90 is seated based on the light receiving signal. It can be determined that On the other hand, for example, the second
When the bit 40 is not seated as shown in FIG. 1B, the moving axis 30 is located above as shown by the broken line in FIG. As a result, no received light output is obtained from the light receiving section 78. Therefore, the control unit 90 can determine that the person is not seated.

On the other hand, if the pulse signal TS1 is not generated from the phase detector 81 and it is determined that the light emitting optical system 71 and the light receiving optical system 76 are not facing the long window 11 of the transmission shaft 10, the control The section 90 drives the motor drive circuit 91 to rotate the transmission shaft 1o as shown at C1 in FIG. During this rotation, the generation of a pulse signal TS1 from the phase detector 81 is monitored, and at the time when this pulse signal TS1 is generated, the light emitting optical system 71 and the light receiving optical system 76 are connected to the long window 11 of the transmission shaft 10. It is determined that the seats are facing each other, and the seating state is determined based on the light reception signal from the light receiving section 78.

Now, if it is determined that the seat is not seated in these seat state determinations, the control section 90 first drives the motor drive circuit 91 in this state to move the transmission shaft 10 in the direction indicated by the arrow C in FIG.
Rotate in one direction. Then, the rotation is stopped at the time when the pulse signal TS2 is generated from the phase detector 82, that is, at the time when the rotation is a little over 90 degrees, and then the rotation is stopped in the opposite direction (arrow C2
) to return the detection disc 80 to a position where the notch 84 is detected by the phase detector 81. That is, this causes the bit 40 to be seated against the rotation stopper 61 of the screw 60. After the rotation operation is completed, the light reception signal from the light receiving section 78 is taken in and the seating state is determined based on the level. If the seating is confirmed by this determination, a start signal is sent to the adjustment control section (not shown). output and start adjustment operation. On the other hand, if seating is not confirmed in the seating determination after the rotation described above, the transmission shaft 10 is reciprocated in the directions of the arrows C1 and C2, and the seating determination is performed after this rotation is completed. Thereafter, the above rotation operation is repeated until seating is confirmed, and when seating is confirmed, the adjustment control section is caused to start adjusting the screw height as described above.

As described above, in this embodiment, by providing the electric screwdriver with a means for determining the seating state, the screw 60
Do not rely on the operator's visual observation to determine the seating state, which cannot be determined simply by aligning the bit 4o with the It is possible to eliminate the problem of shifting to the adjustment operation, and it is possible to significantly reduce the burden on the operator.Furthermore, in this embodiment, when the seating is not confirmed, the motor is driven to move the transmission shaft 10. By rotating the bit 4o, the bit 4o is set to be seated on the head of the screw 6o, so the seating setting operation can be performed automatically without depending on the operator's operation, thereby saving the worker's effort. Not only can this be reduced, but the seating setting can be performed reliably and quickly, so adjustment efficiency can be greatly increased.

Note that the present invention is not limited to the above embodiments. For example, in the above embodiment, an example in which the height of the screw 6o is adjusted has been described, but the present invention may also be applied in adjusting the position of a component. That is, as shown in FIGS. 5(a) to 5(C), a notch 10 for adjustment is provided in the substrate 100 to be adjusted.
1 and a pair of bottles 102 are set upright on the base 110 at a position opposite to the notch 101. As shown in FIG. By seating the bit 40 on the board 102 and rotating the bit 40 using each bin 102 as a fulcrum in this state, the board 100 is rotated.
It may be applied when adjusting the position of. In this case, depending on the orientation of the bit 40, the bit 40 may come into contact with the upper surface of the substrate 100 as shown in FIG.
01 will not be seated. Therefore, even in such a case, if the seating detection and seating setting described in the above embodiment are performed, it is possible to easily and reliably seat the passenger without depending on the operator's operation, as in the previous embodiment.

In this case, as shown in FIGS. 5(b) and 5(c), when the bit 40 is lowered, the bit 40 may get stuck between the side surface of the substrate 100 and each bottle 102. There is. In such a state, the seating detection means 90a determines that the person is seated even though the person is not seated in the notch 101, which is undesirable because it causes a problem in adjustment. To prevent this, the sides of the substrate 10 and each bottle 1
Focusing on the fact that the direction of the gap between the holes 02 and 02 is known in advance, the notch 84 of the detection disk 80 and the direction of the bit 40 are aligned as shown in FIG. 3, and the bit 40 is lowered. Before setting, the initial position of the bit 40 is determined based on the detection results of the detection disk 80 and the phase detector 81 so that the orientation of the bit 40 does not match the orientation of the side surface of the substrate 10 and the gap between the bins 102. It is only necessary to set the bit 40 and then lower the bit 40.

Further, in the above embodiment, the case where a minus type bit is used has been described, but a plus type bit may also be applied. However, in this case, the transmission shaft 1 when setting the seating
The rotation angle θ of 0 may be 45°. Further, the control unit 90 may include input means for setting various parameters such as the rotation angle of the transmission shaft 10 depending on the type of the bit in case the bit is to be replaced and used. Further, in the above embodiment, the seating state is detected by monitoring the position of the upper end of the moving shaft 30, but for example, the bit 4
Marks are displayed on the circumferential surface of 0 and on the surface of the moving axis 30,
The seating state may be detected from the position of this mark. In addition, the structure of the driver body, the configuration of the seating detection means, the types of rotated parts, etc. can be modified in various ways without departing from the gist of the present invention.

〔Effect of the invention〕

As described in detail above, according to the present invention, the position detector is disposed opposite to the side surface of the bit inserted into the distal end portion of the hollow portion of the transmission shaft or the member that moves in the axial direction integrally with the bit, By detecting the axial position of the bit or member using this position detector and determining the seating state of the bit relative to the rotated part based on the detection result, it is possible to easily and easily determine the seating state of the bit relative to the rotated part. It is possible to provide an electric screwdriver that can reliably detect and thereby perform accurate and efficient adjustment.

[Brief explanation of the drawing]

Figures 1 to 4 are for explaining an electric screwdriver according to an embodiment of the present invention. Figure 1 is a configuration diagram of its main parts, and Figures 2 (a) and (b) are illustrations of the seating of the bit. 3 is a plan view showing the configuration of the detection disk and the arrangement position of the phase detector, FIG. 4 is a block diagram showing the functional configuration of the control section, and FIGS. C) is for explaining another embodiment of the present invention, (a>, (b) is a plan view for explaining the seating state of the bit with respect to the adjustment target, and (C) is a side view of (b). 6 is a side sectional view showing the configuration of the main body portion of the driver for explaining a conventional electric screwdriver. 10...Transmission shaft, 11...Long window, 12...Steel ball ,
13...Groove, 20...Base, 21...Bearing, 22
．． 23... Nut, 30... Moving axis, 32, 51.
...Compression spring, 40...Bit, 41...Recess, 4
2... Bin, 50... Adapter, 52... Retaining ring, 60... Screw, 61... Rotation stopper, 71... Light emitting optical system, 72. 75... Support column, 73. 77... Optical fiber, 74... Light emitting section, 76... Light receiving optical system,
78... Light receiving section, 80... Detection disk, 81.82.
. . . Phase detector, 84 . . . Notch, 90 . . . Control unit, 90a .
...Motor drive circuit, 100... Board, 101...
Notch, 102...bin. Applicant's agent Patent attorney Takehiko Suzue (a) (b) Figure 2 Figure 3 Figure 4WJ (a) Figure 5

Claims (3)

[Claims] (1) A transmission shaft that has a hollow portion at least at its tip and rotates due to the driving force of a rotational drive source, and a bit that is inserted movably in the axial direction into the hollow portion of the transmission shaft and rotates integrally with the transmission shaft. A spring that always biases this bit in the direction of the tip, and a position detector arranged opposite to the side of the bit or a member that moves in the axial direction integrally with this bit, and this position detector detects the position of the bit or member. An electric screwdriver characterized by comprising seating determination means for detecting the position in the axial direction and determining the seating state of the bit relative to the rotated component based on the detection result. (2) The seating determination means includes a rotary plate that rotates integrally with the transmission shaft, and a determination timing that detects the rotational phase of the rotary plate and generates a timing signal for determining the seating state based on the detected output. An electric screwdriver according to claim (1), further comprising a specifying means. (3) The seating determination means drives a rotational drive source to rotate the bit by a predetermined angle when determining that the bit is not seated on the rotated component, and seats the bit again during or after the rotation. The electric screwdriver according to claim (1), further comprising seating setting control means for determining the state of the electric screwdriver.