JPH0679032U - Limit device - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a limiter having a simple configuration and capable of setting a required number of rotations from an initial position on a rotating shaft. [Structure] A large gear 24 meshes with a small gear 16 directly connected to an input shaft, and the large gear 24 and a sprocket 28 are integrated.
A working piece 50 is projectingly provided on the chain 32 stretched between the sprocket 28 and the chain wheel 30. Action piece 5
0 is the limit switch 46 in the initial setting of the first position.
To operate the limit switch 48 at the second position where the required number of rotations is set. Each limit switch 4
The positions of 6, 48 can be finely adjusted individually by the feed screws 38, 40. If necessary, limit switch 49
Can be added and an intermediate position can be set.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a limit device for setting a first position which is initially set and a second position after a predetermined number of rotations from the first position, and specifically, for setting an opening / closing position of an electric seat shutter. Related to the limit device.

[0002]

[Prior art]

 Conventionally, as a method of automatically stopping a rotating member that rotates forward and backward by electric power at both ends where the rotation direction is reversed, a device that optically or magnetically or electromagnetically senses the moving body itself by a sensor and stops it. Or, there is a device that allows the moving body itself to mechanically operate a switch or a clutch. Since these devices have to be installed for each facility, they are difficult to unitize and are easily affected by disturbance. Therefore, a number of unitized limit devices have been devised that can be operated in conjunction with the drive shaft.

As one of them, there is one that electronically controls the rotational movement by an encoder, but it requires sophisticated electronic technology and the device is expensive. Also, there is a counter that sets the initial setting position to zero and sets and counts a predetermined number of times, and that generates a signal at the zero position and the set number of positions. In this case, since it is digital, it is mechanically difficult to perform analog continuous fine adjustment. Such a limit device lacks versatility as a unit type product distributed in the general market.

On the other hand, as a mechanically simple and inexpensive unit type limit device, each limit switch for initial setting and number of times setting is attached to one small gear that can be directly connected to the drive shaft to be controlled. There is one in which two large gears provided integrally with a cam to be operated are meshed. When adjusting the initial setting position and the number of times setting position, this device shifts the large gear in the axial direction to temporarily release the meshing with the small gear and change the meshing position of the large gear to the small gear to another position. It is designed to be transferred to.

[0005]

[Problems to be solved by the device]

 However, in such a conventional limit device using a gear train and a cam mechanism, the minimum unit of fine adjustment is one gear tooth, and finer position adjustment than that is impossible. Also, since the range of number of revolutions that can be set is related to the module of the gear and the reduction ratio, it is possible to support any range of number of revolutions under the conditions of the storage space of the unit or the allowable degree of fine adjustment. It is not possible to unambiguously determine the exact gear set.

In addition, it is necessary to prevent overrun so that the limit switch does not cancel its operating state due to inertial movement of the drive system from the actuation of the limit switch to the stop of the drive shaft. However, it is often difficult to solve this problem only within the frame of the cylindrical cam shape where the circumferential length is limited, and in this conventional cylindrical cam type limiter, it is considered to set the stop position in the middle. It has not been.

As described above, in order to unitize the structure of the cylindrical cam type limiter described above, it is necessary to prepare several kinds of gear trains and cam mechanisms according to the range of the set number of times. An object of the present invention is to provide a limit device capable of performing analog continuous fine adjustment of the rotation number counting position, setting an intermediate stop position, and supporting a wide range of rotation number setting with only one unit model. And

[0008]

[Means for Solving the Problems]

 The limit device according to the present invention includes a small gear that rotates together with the input shaft, a sprocket that rotates integrally with the large gear that meshes with the small gear, and a shaft that is installed at a position separated from the sprocket. It comprises a chain wheel having the same pitch diameter as that of the sprocket, which is supported and guides the endless chain to be stretched between the sprocket and the sprocket.

[0009] Furthermore, a feed screw is arranged in parallel along each of the straight line portions formed by the revolving chain orbit, and is attached to each slide base that is screwed into the feed screw and moves in parallel with the chain. Place limit switches on each. A working piece for operating the limit switch is projected at at least one position of the chain.

It is preferable that such action pieces be continuously provided over a plurality of pieces of the chain. Further, irrespective of the feed screw, at least one limit switch may be fixed to the base plate in the middle of the movement path of the operating piece so that the operating piece switches the switch.

[0011]

[Action]

 In such a configuration, the rotation of the small gear that makes the same rotation as the input shaft is reduced in speed and transmitted to the sprocket via the large gear. The moving distance of the chain that meshes with the sprocket is proportional to the rotation angle (number of rotations) of the input shaft. Therefore, the rotation angle of the input shaft can be controlled according to the movement distance of the chain. Therefore, the range of the number of rotations of the input shaft is made to correspond to the range spanning both straight parts of the chain.

With the forward and reverse rotation of the input shaft, the action piece moves between the limit switches of the slide table that meshes with the feed screws provided along the chain, and either limit switch Engage to activate it. Therefore, one of the limit switches is made to correspond to the initial setting position of the rotation of the input shaft as the first position, and the position reached by the action piece when the input shaft has passed the predetermined number of rotations from this is set as the second position and the other position is set as the other position. Match the limit switch.

Then, the movable table on which the limit switch is mounted is moved by the one feed screw to a position where one of the limit switches is switched by the action piece in the first position. Further, for the second position of the working piece, the other limit switch is similarly moved to the operating position by the other feed screw.

As described above, it is possible to arbitrarily set the position at which the operating piece continuously engages with the limit switch by operating the feed screw, and the operating piece can be moved to the operating piece at the arbitrarily positioned first and second positions. A limit switch can be activated to generate a signal. With this signal, the drive system can be automatically stopped or reversed, and in the case of manual rotation operation, this signal turns on the lamp that indicates the rotation limit or starts / stops the alarm buzzer. Available.

Moreover, by arranging the action pieces continuously over a plurality of pieces of the chain, the action pieces pass through the limit switch by the movement of the chain due to the inertia of the drive device after the limit switch is activated, and the operating state of the limit switch is changed. The phenomenon that disappears will disappear. This eliminates the need for a strict braking device and prevents malfunctions that occur when the operating switch is pressed incorrectly when the operating piece is overrunning the limit switch. Further, since the movement stroke of the action piece by the chain can be sufficiently long, it is possible to add another limit switch corresponding to a predetermined position on the way from the first position to the second position, It is possible to output a signal even when the rotation of the input shaft is an intermediate position between the first position and the second position. In this case, the added limit switch can be ignored on the electric circuit, and the signal generation position can be variously changed and programmed by the electric combination.

[0016]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a plan view of a limiting device according to the present invention. In the figure, reference numeral 10 is a base frame of a limiter, which pivotally supports an input shaft 12. The input shaft 12 is directly connected to the shaft 6 to be controlled and rotates integrally with the shaft 6 coaxially therewith. A pin 14 is fixed to the input shaft 12 so as to pass through the shaft at a right angle, and engages with a notch groove 20 provided in a boss 18 of a small gear 16 fitted slidably in the axial direction. The pinion gear 16 is crimped to the pin 14 by the coil spring 22 so that it can be slid toward the outer end of the input shaft 12 to release the engagement between the pin 18 and the notch groove 20. (See Figure 2).

A large gear 24 meshes with the small gear 16, and is integral with a sprocket 28 that is pivotally supported by a fixed shaft 26 provided on the base frame 10 and rotates coaxially. A chain wheel 30 has a pitch diameter equal to that of the sprocket 28 and extends and guides a chain 32. A spindle 34 of the chain wheel 30 is fixed to the base frame 10 with a predetermined distance from the sprocket 28.

Feed screws 38 and 40 are provided on both straight line portions of the chain 32 stretched between the sprocket 28 and the chain wheel 30, respectively. Further, slide bases 42 and 44 are screwed onto the feed screws 38 and 40, respectively, and limit switches 46 and 48 are mounted on the slide bases 42 and 44, respectively. A partial section of the chain 32 is constituted by a seated link 33 for a required length, and the action pieces 50 are individually screwed to each link 33 and are continuously arranged in a caterpillar shape, and the action pieces 50a located at both ends are provided. , 50b are chamfered so as to smoothly engage with the limit switches 46, 48. Each of the feed screws 38 and 40 is provided with a lock nut 52 or 54 for preventing the rotation of the screw to fix the position. Reference numeral 56 is a guide member that cooperates with a shelf plate 58 that supports the slack of the chain 32, and guides the chain portion, on which the action piece 50 is mounted, by loosely fitting and guiding the sliding bases 42 and 44 to stabilize the movement. provide.

In the first embodiment of the present invention, the limit switches 46 and 48 are mounted in such an actuator orientation that the moving range of the working piece 50 within the orbit of the chain 32 is the side half the circumference of the chain wheel 30. Yes, but of course the opposite is also possible. Therefore, the action piece 50 is set to a position where it is engaged with the limit switch 46, for example, with respect to the initially set first position. Therefore, the small gear 16 is moved toward the outer end of the input shaft 12 against the urging force of the coil spring 22, and the meshing with the large gear 24 is released (see the chain double-dashed line in FIG. 2). As a result, the large gear 24 becomes free, and the position of the action piece 50 can be moved to a predetermined position. The first position is set by engaging the small gear 16 again with the large gear 24 and returning the notch groove 20 to the position where it engages with the pin 14. The fine adjustment of the gear position by one pitch or less is possible by operating the feed screw 38.

In the arrangement shown in the drawing, the input shaft 12 is at the limit position, for example, the first position, which the work piece 50 has reached by moving in the direction of the arrow U when rotated in the direction shown by the arrow R. When the input shaft 12 is rotated in the direction indicated by the arrow L, the action piece 50 moves in the direction indicated by the arrow V toward the limit switch 48. The second position is set by operating the feed screw 40 so that the operating piece 50 operates the limit switch 48 when the input shaft 12 is rotated a required number of times. After the setting of the positions is completed, the lock nuts 52 and 54 are tightened in order to fix the set positions of the limit switches 46 and 48 to prevent the feed screws 38 and 40 from rotating.

The orbit of the chain 32 can be made sufficiently long depending on the distance between the shafts of the sprocket 28 and the chain wheel 30, and the operating piece 50 overruns the operating position due to the inertia after the limit switch is operated, thereby operating the switch. Sufficient length is guaranteed so as not to invalidate. FIG. 1 shows a state in which the action piece 50 moves by the distance d by the inertial force after actuating the limit switch 46 and then stops.

Next, a second embodiment of the present invention will be described. In FIG. 1, the additional fixed base 45 and the limit switch 49 are shown by a chain double-dashed line. In the figure, the feed screw 40 is inserted through the fixed base 45, but it is not in a screwing relationship and is unrelated to the rotation of the feed screw 40. In the second embodiment, when setting the first position and the second position, the input shaft 12 is stopped at a position of a required intermediate rotation angle (number of rotations). Therefore, by the same procedure as in the first embodiment, the engagement between the small gear 16 and the large gear 24 is released to disconnect the working piece 50 and the input shaft 12 from each other. After moving the free action piece 50 to the position where the fixed limit switch 49 is operated, the large gear 24 is returned to the normal position.

The positions of the upper limit switch 46 and the lower limit switch 48 are assigned based on the relationship between the rotational intermediate position of the input shaft 12, the action piece 50, and the limit switch 49 set as described above. The positions of the upper limit switch 46 and the lower limit switch 48 are set by operating the feed screws 38 and 40 in the same manner as in the first embodiment.

In FIG. 1, when the input shaft 12 is rotated in the direction of the arrow L, the action piece 50 disengages the limit switch 46 and moves toward the added limit switch 49. The work piece 50b engages with and operates the additional limit switch 49 before the limit switch 48 is operated, and the input shaft 12 moves at a position of a predetermined number of rotations before reaching the second position. Generate a signal. The limit switch 49 can be jumped on the electric circuit so that the engagement with the working piece 50 is ignored.

FIG. 3 shows an application example in which the limit device of the present invention is attached to shutter equipment. In the figure, reference numeral 1 denotes a shutter, and the right half shows the open state of the shutter 1 and the left half shows the closed state of the shutter 1. Reference numeral 2 is a shutter guide frame, and 3 is an opening / closing operation panel. The shutter motor 1 is opened and closed by controlling the brake motor 4 with a speed reducer from the opening / closing operation panel 3 to reverse the shutter winding drum 5 forward and backward and winding the shutter back on the drum 5. A limiting device 8 according to the present invention is mounted on the upper part of the guide frame 2 by a base frame 10, and the shutter winding drum shaft 6 and the input shaft 12 of the limiting device 8 are directly connected.

In this application example, when the shutter 1 is rolled up and is fully opened, the input shaft 12 is in the first position, and the brake motor with reduction gear 4 is stopped by a signal from the operation of the limit switch 46. When the shutter 1 is in the fully closed position, the second position is set, and the brake motor with reduction gear 4 is stopped by a signal from the operation of the limit switch 48. Further, the intermediate position is set so that the shutter 1 can be stopped and held at an appropriate opening height h, and the limit switch 49 functions. Since the limit switch 49 can be ignored electrically, when the operating piece 50 passes through the limit switch 49 to activate the limit switch 48, the shutter lower end 9 must reach the fully closed position of the second position. It can be stopped. Therefore, normally, the lower end 9 of the shutter can be maintained, for example, at a height h at which the minimum entrance / exit can be secured, and can be set so as to move to the first position for full opening if necessary.

Further, by configuring the normal path of the action piece 50 between the limit switch 49 and the limit switch 48, the shutter lower end 9 can be normally moved in and out from the closed position between the second position and the intermediate position. It can also be set to open and close up to the required height h. In this case, the lower end 9 of the shutter can be moved to the first position as necessary to set the entrance to the fully open position.

[0028]

[Effect of device]

 As described above, the limit device according to the present invention is capable of continuously finely adjusting the initial setting position and the position after the required number of rotations with the above-described simple structure. In addition, a unit that can handle a wide range of number of rotations can be configured with the same component, and the length of the working piece is sufficient, so movement due to inertia can be allowed. Therefore, when the electric signal generated at each set position is used for stopping or reversing the electric drive system, it is possible to omit the electric device circuits such as the self-holding circuit and the strict sudden braking circuit.

Moreover, since the fixed limit switch can be additionally installed to set the intermediate position, it is possible to save the energy because it does not always rotate over the set entire area, so that the economical efficiency can be improved.

Thus, for example, when the limit device according to the present invention is applied to the opening / closing device of the electric seat shutter, the entire entrance / exit does not have to be opened / closed each time, so that the opening / closing time can be shortened and the indoor / outdoor position can be constantly maintained. The unique features of the sheet shutter, such as heat retention and dust protection, can be made to function remarkably.

[Brief description of drawings]

FIG. 1 is a plan view showing an internal mechanism of a limit device according to the present invention.

FIG. 2 is a II-II shown in FIG. 1 of the limit device according to the present invention.
It is a longitudinal cross-sectional view of the portion along the line.

FIG. 3 is a front view of an electric seat shutter facility equipped with a limit device according to the present invention.

[Explanation of symbols]

 8 limit device 10 base frame 12 input shaft 16 small gear 24 large gear 26 fixed shaft 28 sprocket 30 chain wheel 32 chain 34 support shaft 38, 40 feed screw 42, 44 sliding base 45 fixed base 46, 48, 49 limit switch 50 Action piece

Claims (3)

[Scope of utility model registration request] 1. A device for setting the number of rotations of a rotating shaft, comprising: a small gear that rotates together with an input shaft; and a sprocket that rotates integrally with a large gear that meshes with the small gear.
A straight line formed by the sprocket and a chain wheel having the same pitch diameter, which is pivotally supported by a shaft installed at a position distant from the sprocket and guides an endless chain between the sprocket and the sprocket. A feed screw is arranged in parallel along each of the portions, and a limit switch is placed on each slide table that is screwed into the feed screw and moves parallel to the chain, and at least one position of the chain A limit device in which a working piece for operating the limit switch is provided on the protruding portion. 2. The limit device according to claim 1, wherein the action piece is continuously provided over a plurality of chain pieces. 3. The working piece according to claim 1, wherein at least one limit switch is fixedly provided on the base plate independently of the feed screw in the middle of the movement path of the working piece, and the switch is operated by the working piece. Limit device.