JPS5823688B2 - limit switch device - Google Patents

Description

[Detailed description of the invention] The present invention is connected to an electric motor for opening and closing a door shutter,
The present invention relates to an improvement in a limit switch device for detecting the opening/closing end of a shutter and stopping a motor.

Conventionally, in this type of limit switch device, manual shaft rotation corresponds to the opening/closing stroke of the shutter.

Since the rotation speed of the cam is reduced to one rotation of the switch actuating cam, the rotational speed of the cam is very slow, and therefore, the contact opening/closing of the switch becomes inaccurate, resulting in extremely low detection accuracy.

In order to eliminate such drawbacks, the present invention provides a plurality of switch actuating cams and makes them differentially actuate each other, and when these cams are arranged in parallel with the same phase, the switch is made to actuate differentially. To provide a limit switch device that can perform highly accurate detection over a wide range without significantly decelerating the rotation of the motor.

If the embodiment of the present invention is explained with reference to the drawings, the driving force is connected between two occluded circular support plates 10a and 10b which are connected and arranged in parallel at appropriate intervals by three tie rods 9. A gear section 1, intermediate reduction gear shaft sections 2 and 3, differential gear drive shaft section 4, cam disc differential shaft section 5, micro switch section 6, switch operating section 7, and forward/reverse switching section 8 are arranged. be.

The structure of each of the above parts will be described in detail below.The intermediate reduction gear shaft parts 2 and 3 are connected to the fixed shafts 2a and 3a, respectively, and are equipped with three sets of stepped pinion gears 2b and two sets of stepped pinion gears 3b, which are the same in shape.
are fitted loosely, and the pinion gears 2b and 3b are meshed with each other, and one of the pinion gears 2b is connected to the drive gear 1.
(a); as is well known, the speed is reduced with an appropriate speed reduction ratio.

The differential gear drive shaft section 4 has a cylindrical shaft 4b loosely fitted onto a fixed shaft 4a,
A reference gear 14 is fixed to the center of the cylindrical shaft 4b with a loose fit in the axial direction, and spacers 34a and 34b are loosely fitted in the axial direction on both left and right sides of the gear through friction clutch members 24, 24 such as wave washers. fixed spacers 34c and 34d which are loosely fixed in the axial direction, and further have the forward rotating gear 14a and the reverse rotating gear 14b loosely fitted on the outer sides in the axial direction, and are loose in the axial direction.
A forward rotating gear 14c and a reverse rotating gear 14d of the same shape are loosely fitted through the
a, 14c and a reverse rotation gear 14b.

14d are arranged symmetrically with respect to the reference gear 14.

The reference gear 14 meshes with the final gear of the pinion gear 2b of the intermediate reduction gear shaft 2 to transmit its rotation, and also connects the gears 14a, 14c, 14b, and 14d with friction via friction clutch members 24, 24. It is meant to be rotated.

Therefore, if a force that restricts rotation is applied to the gears 14a, 14c or 14b, 14d and exceeds the transmission force of the friction clutch member 24, the reference gear 14 continues to rotate.

However, among these gears, the gear that is restrained will stop.

The cam disk differential shaft portion 5 has a cylindrical shaft 5b loosely fitted onto a fixed shaft 5a,
A second reference gear 15 is fixed to the center of the cylinder shaft 5b with a loose fit in the axial direction, and another cylinder shaft is connected to the left and right sides of the cylinder shaft 5b through friction clutch members 25 and 25 such as corrugated washers. 35a,
A reference cam disk 12 for forward rotation and a reference cam disk 13 for reverse rotation are loosely fitted in the axial direction to the center portions of the cylinder shafts 35a and 35b, respectively. The cam disks 12 and 13 are sandwiched between the forward rotation geared sub cam disks 12a, 12b and the reverse rotation geared sub cam disks 13a, 13b are connected to the cylinder shaft 35a.

35b, and in this way, the forward rotation cam disks 12, 12a, 12b and the reverse rotation cam disk 1''3.
13a, 13b (!r are arranged symmetrically with respect to the reference gear 15.

The reference gear 15 is meshed with the reference gear 14 of the differential gear drive shaft section 4 to transmit its rotation, and is also connected to the cylindrical shafts 35a, 35b and the reference cam disk 12 via the friction clutch members 25 and 25. .13 is rotated by friction, and the sub-cam discs 12a, 12b and 13a are roughly geared.

13b respectively to the gear 1 of the differential gear drive shaft section 4.
4a, 14c and 14b, 14d are meshed with each other.

The above cam disks 12, 12a for forward rotation.

12b and counter-rotating cam disk 13.13a.

13b are formed to have the same diameter, and each has a cutout recess 22 at an appropriate position on the circumferential surface.
a, 23a and locking protrusions 22b and 23b are provided.

The microswitch unit 6 includes a microswitch 6a for limiting the number of rotations in the forward direction of the driving gear 1a and a microswitch 6b for limiting the number of rotations in the opposite direction.
They are clamped and tightened in series between 0a and 10b to correspond to switch actuation members 17a and 17b, which will be described later, respectively.

The switch actuating portion 7 has switch actuating members 17a and 17b loosely fitted on the fixed shaft 7a on the left and right sides of the fixed shaft 7a via a spacer 7b, thereby forming the forward rotating cam disks 12, 12a and 12b and the reverse rotating cam disk, respectively. Roller holders 18a, 18a and 18b, 18 correspond to the plates 13° 13a, 13b, respectively.
Rollers 19a and 19b are rotatably pivotally connected via springs 20 and 20, and are normally pressed against the circumferential surfaces of cam discs 12, 12a, 12b and 13, 13a, 13b, and a cam depression projection 21a .

It is brought into contact with the microswitches 6a and 6b via 21b.

The forward/reverse switching unit 8 connects the switching bundle 8c to the support plates 10a, 1
0b so that it can be rotated in stages, and its bearing protrusion 8a or 8b is connected to the forward rotating cam disks 12, 12.
a, 12b locking protrusion 22b or reverse rotation cam disc 1
3,13a.

The cam discs are selectively engaged with the locking protrusions 23b of the cam discs 13b to restrain the forward or reverse rotation of these cam discs.

It is configured as described above, and is connected to a door shutter opening/closing electric motor (not shown) via a driving gear 1, and, for example, at the open end (upper end) of the shutter, the forward rotating cam disc 1
2. When the notch recesses 22a and the locking protrusions 22b of each of 12a and 12b are located at random with respect to each other, the forward/reverse switching bundle 8c is switched to the forward rotation direction and the yielding protrusion 8 is
a can be engaged with the locking protrusions 22b of the forward rotating cam discs 12, 12a, 12b, and the cam circle When the plate differential shaft portion 5 is driven in the forward direction to move the shutter downward, the locking protrusions 22b of the forward rotating cam discs 12゜l2a, 12b are sequentially engaged with the accommodating protrusions 8a of the forward/reverse switching handle 8c. At the same time, the notched recesses 22a of the cam disks overlap in the same phase to form a forward rotational cam lock state, and the roller 19a of the switch actuating member 17a locks the rotation of the spring 20. Engages with the notch recess 22a of the cam disk by elastic force,
The cam depression projection 21a releases the microswitch 6a.

Next, while maintaining the cam lock state in the forward rotation direction, move the shutter down to just before the closed end (downward movement), switch the forward/reverse switching handle 8c to the neutral position, and set the cam discs 12, 12a,
Release the restraint of 12b.

By setting this state, the forward rotation direction control circuit can be always opened at the lower end of the shutter to stop the shutter drive motor.

Next, in the same manner, at the closed end (descending end) of the shutter, the reversely rotating cam disks 13, 13a.

When the notched recesses 23a and the locking protrusions 23b of the cam disc 13b are located randomly, the forward/reverse switching handle 8c is switched to the reverse direction, and the cam disk differential shaft 5 is driven in the opposite direction to close the shutter. If you move it up, the reverse rotation cam disk 1
3. The locking protrusions 23b of 13a and 13b sequentially engage the yielding protrusion 8
At the same time, the cutout recesses 23a of these cam disks overlap in the same phase to form a reverse rotational cam lock state, and the roller 19b of the switch actuating member 17b Engages with the notch recess 23a of the cam disc by the elastic force of the spring 20,
Release the cam lowering projection 21b or the microswitch 6b.

Next, while maintaining the reverse rotation direction cam O'y position, move the shutter upward to just before the open end (ascending end), switch the forward/reverse switching handle 8c to the neutral position, and then move the cam disks 13, 1 to the neutral position.
Release the constraints of 3a and 13b.

If this state is set, the reverse rotation direction control circuit can be always opened at the ascending end of the shutter to stop the shutter opening/closing motor.

If the shutter is set as described above and the forward/reverse switching handle 8c is switched to the neutral position to open/close the shutter, it will always automatically stop at the open end (upper end) and the closed end (lower end).

Now, the number of teeth of reference gears 14 and 15 is 51T, and gear 1
The number of teeth of 4a is 54T, and the gear 1 of the cam disc that meshes with this
If the number of teeth of gear 2a' is 48T, the number of teeth of gear 14c is 48T, and the number of teeth of gear 12b' of the cam disc that meshes with these is 54T, then the cam disc for one revolution of reference gears 14 and 15 is 12 and the rotation speeds of the geared cam discs 12a and 12b are as shown in the following table.

As is clear from the above table, when the switching handle is set to the neutral position, the reference gear 14 changes from the first cam lock state to the next cam lock state of the cam discs 12, 12a, 12b.
．． 15 rotates 72 times, and the number of rotations of the reference gear 14.15 until the switching handle 8c is switched to the forward rotation position and the cam disks 12.12a, 12b are in the cam lock state from any random position is 100 rotations. It will never be surpassed.

Therefore, the stroke between opening and closing of the shutter is the same as that of the reference gear 14.
It can be controlled over a stroke corresponding to 15 hundred revolutions to a stroke corresponding to 72 revolutions.

The same holds true for reverse rotation.

Also, the reference gear 14 rotates 72 times and returns to the cam lock state, but during this rotation, the relative angle between the geared cam disk and the gear is 360 degrees when the notches of each cam disk come closest to each other. The number divided by the larger number of the teeth ratio, that is, 3
60°/9=40°, therefore, if the central angle formed by the notch of each cam disc is set within 40°, the switch actuating portion can be operated over almost the entire area from the cam lock state to the cam lock state again. The rollers do not fit into the notches of any of the cam discs.

In this way, a reference cam disk that rotates integrally with the reference gear and a cam disk that rotates once each nine times with respect to the reference cam disk are coaxially arranged in parallel with the same outer diameter, By configuring the cam disks to rotate non-interferingly with each other and with friction relative to the reference gear, it is possible to form a cam lock state within at least 100 degrees of the rotation axis of the reference gear. The fundamental technical idea of the present invention is that the rotation of the cam discs can be limited to an extremely low level, and the number of revolutions required until all the notched recesses of the cam discs overlap can be kept extremely low. It is what it is.

In the above embodiments, either the first and second reference gears are meshed with each other to transmit frictional rotation from the second reference gear to the reference cam disk, or the second reference gear is not used. Next, an embodiment in which a sub-cam disk is added will be described.

That is, as shown in FIG. 7, an axial keyway is provided on the outer periphery of the rotating shaft 14, and a tongue reference gear 54 and a tongue spacer 55.5 are provided.
Gears 56, 57, 58, 59, 6 with different diameters are placed on both sides of the reference gear 54, and the gears 56, 57, 58, 59, 6 are fitted loosely in the axial direction.
0, 61, 62, 63 and the friction clutch 64 are loosely fitted,
The friction clutch 64, the spacer 55 and the adjacent spacer 55'
The gears are clamped by.

45 is Bushnut. Note that even one friction clutch does not pose any functional problem.

The tongued reference gear 54 is meshed directly with the driving shaft or through a suitable speed reduction means.

Therefore, if the rotation from the driving shaft is transmitted to the reference gear 54, the gears 56 to 59 and the gears 60 to 63 will be transferred to the friction clutch 6.
Rotation is transmitted via 4.

On the other hand, a geared cam disk 66.67° 68.69 for forward rotation and a geared cam disk 70, 71° 72.73 for reverse rotation are attached to a fixed shaft 65 arranged parallel to the rotating shaft 44. These cam disks are rotatably fitted loosely in the axial direction to the extent that they do not come in close contact with each other, and these cam disks are held on the shaft 65 by a spacer 74.

75 is Bushnut.

In this case, the geared cam discs 66 to 69 are connected to the gears 56 to 69.
59 and similarly geared cam discs 70 for reverse rotation.
-73 mesh with gears 60-63, respectively.

In this way, each geared cam disk on the fixed shaft 65 is connected to the rotating shaft 4.
The rotation is transmitted by each gear on the top.

The geared cam disks 66 and 70 correspond to the reference cam disk, and the other geared cam disks 67, 68, 69 and 71,
Reference numerals 72 and 73 perform functions equivalent to sub-cam disks.

In addition, each cam disk is formed to have the same size and shape, and has cutout recesses and locking protrusions spaced apart at regular intervals on its outer periphery as in the previous embodiment, and the other structures are the same as in the previous embodiment. It is.

If the number of sub-cam disks is increased in this way, for example, when the friction clutch 64 acts as a zero-slip clutch as in the previous embodiment, the number of rotations of each sub-cam disk relative to one revolution of the reference cam disk can be increased. hundred.

10 Hundred, 7, when the switching bundle is in the neutral position,
The reference gear rotates 9 x 8 x 7 = 504 times during the transition from the first cam lock state to the next cam lock state of each cam disk, and the cam circle is rotated by switching the switching bundle to the forward rotation or reverse rotation position. The plate can be brought into the cam lock state immediately from any random position without exceeding the number of revolutions of the reference gear until the plate is in the cam lock state. A reference gear that rotates, a plurality of forward rotating gears with different numbers of teeth that rotate by friction due to the rotation of the reference gear, and a plurality of reverse rotating gears that also have different numbers of teeth are coaxially supported, and are opposed to the axis. A forward rotation reference cam disk and a reverse rotation reference cam disk that are frictionally rotated by the rotation of the reference gear are mounted on support shafts arranged in parallel with each other, and gears that mesh with the frictionally rotated forward and reverse rotation gears, respectively. The reference cam disc and the secondary cam disc are formed to have the same shape, and a locking notch is provided on the outer periphery of each cam disc. A recess is provided, and a forward/reverse switching member is disposed on the outer periphery of the forward and reverse cam disks to engage and disengage the forward rotating cam disk and the reverse rotating cam disk, respectively. , the limit switch device is characterized in that when the notch recesses of all the cam disks rotating in the same direction are arranged in parallel in the same phase, the switch actuating member is fitted into the notch recesses. Therefore, by making multiple cam discs and differentially operating them, when used in connection with a door shutter opening/closing electric motor, etc., the cam discs rotate in the forward direction and the opposite direction at the upper and lower end of the shutter. By making adjustments so that the switch actuating members fit into the notched recesses provided on the outer periphery of the cam disk, the shutter can be stopped accurately at the upper and lower limits of the shutter, and it is possible to stop multiple shutters accurately. The cam disc is driven via a differential gear mechanism, so by appropriately setting the number of differential gear trains and the number of teeth on each gear, high accuracy can be achieved over a wide stroke range of the shutter. can be controlled.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention; FIG. 1 is a partially cutaway front view, FIGS. 2 to 4 are longitudinal developed views of main parts, and FIGS. 5 and 6 are cam circles. Figure 7 is a longitudinal cross-sectional view showing another embodiment of the present invention. ...Reference gear, 14a-1
4d...Gear, 24...Friction clutch member, 12, 12a. 12b... Cam disk for forward rotation, 13.13
a. 13b... Cam disc for reverse rotation, 22a, 2
3a...Notch recess, 22b, 23b...
・Latching protrusion.

Claims (1)

[Claims] 1. A reference gear that is connected to an appropriate drive mechanism and rotates.A plurality of gears that frictionally rotate due to the rotation of the reference gear, and a plurality of gears that rotate in a different forward direction and a plurality of gears that rotate in a reverse direction that have different numbers of teeth are coaxially connected to each other. a forward rotation reference cam disk and a reverse rotation reference cam disk that are supported by support shafts arranged in parallel opposite to the shaft and frictionally rotated by the rotation of the reference gear, and forward and reverse rotations that perform the frictional rotation. A forward rotating sub cam disk and a reverse rotating sub cam disk having gears meshing with the rotating gear are supported, the reference cam disk and the sub cam disk are formed to have the same shape, and each cam disk is A locking part and a notched recess are provided on the outer periphery of the cam disc, and a locking part and a notch are provided on the outer periphery of the forward and reverse rotating cam discs, respectively. A switch actuating member is configured to fit into the notch recesses of all the cam disks rotating in the same direction when the recesses of all the cam disks rotate in the same direction and are arranged in parallel with the same phase. A limit switch device featuring: