JPH0330560Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a braking device for a retractable screen.

This type of retractable screen has a coil spring built into the retractable shaft of the screen, such as an openable insect screen door or an insulating film that can be opened and closed in a refrigerated case, so that when the screen is pulled out, the retractable shaft will There is a known device in which a repulsive force is stored in the coil spring by the twisting of the coil spring as it rotates, and the screen is automatically wound up using this repulsive force as a driving source when the screen is wound up.

However, in such roll-up screens, the force of the springs is usually provided with sufficient margin, so when the screen is rolled up, the screen may be rolled up all at once at a very high speed. There were disadvantages in that members such as the winding box collided violently with the winding box, producing noise, and the screen, frame, winding box, etc. were easily damaged by the impact.

The present invention aims to provide a braking device with a simple structure that can wind up the screen at a slow speed by increasing the rotational resistance of the winding shaft. A disk attached to a winding shaft is rotatably fitted into the hole, and at least one depression is provided on the outer peripheral surface of the disk, and the disk can be displaced in the direction of centrifugal force by rotation of the disk inside the depression. At least one recess into which the sphere can fit is provided on the inner peripheral surface of the support hole in the fixing plate, and the recess on the outer peripheral surface of the disc is formed to a depth that allows the sphere to completely fit therein, and the support hole in the fixed plate is provided with at least one recess into which the sphere can fit. It is characterized in that the recess on the inner peripheral surface of the hole is formed to be shallower than the diameter of the sphere.

Hereinafter, embodiments of the present invention will be described in detail based on the drawings. Figures 1 and 2 illustrate the case where the present invention is applied to an insect-proof screen door that opens and closes vertically. , 1 indicates a winding box, and this winding box 1 consists of a cover 2 having a rectangular cross section and having an outlet 2a for a net-like screen S, and end plates 3 attached to both ends of the cover 2. A take-up shaft 4 for the screen S is rotatably mounted inside the take-up box 1.

The winding shaft 4 has both ends inside thereof.
A coil spring (not shown) fixed to the winding box 1 is built in, and when the screen S is pulled out, a repulsive force is stored in the coil spring by the twisting of the coil spring as the winding shaft 4 rotates. When winding up the screen S, this repulsive force is used as a driving source to automatically wind up the screen S. When the winding shaft 4 is rotatably supported by the winding box 1, A square shaft 5 protruding from one end of the winding shaft 4 is fitted into a square hole 8 on one side of a disk 7 in the braking device 6, and a round hole 9 formed on the other side of the disk 7 is inserted into the end plate. The other end of the winding shaft 4 is supported on the winding box 1 by appropriate means.

The braking device 6 is for winding up the screen S at a slow speed by applying resistance to the rotation of the winding shaft 4, and includes a fixing plate 11 fixedly attached to the inside of the cover 2. , the square hole 8 is formed in the winding shaft 4.
and the circular plate 7 fixedly attached by a square shaft 5, and a circular support hole 1 provided in a fixed plate 11.
A disc 7 is rotatably fitted in the disc 7, a recess 13 is provided on the outer peripheral surface of the disc 7, and a sphere 14 is accommodated in the recess 13 so as to be displaceable in the direction of centrifugal force by rotation of the disc 7. A concave spherical recess 15 is provided on the inner peripheral surface of the support hole 12 in the fixed plate 11. The recess 13 is formed to have a depth at least equal to the diameter of the sphere 14 so that the sphere 14 can completely enter therein, while the recess 15 has a depth that is at least the same as the diameter of the sphere 14, as shown in FIG. The depth is made shallower than the diameter of the sphere 14 so that the sphere 14 does not fit in completely but partially, and the sphere 14 in the recess 13 repeatedly fits into the recess 15 and retreats into the recess 13. The disk 7 is configured to rotate. Note that the recess 15 may be formed into a conical shape.

In the insect-proof screen door having the above configuration, when the winding shaft 4 is rotated by the coil spring when winding up the screen S, centrifugal force acts on the sphere 14 housed in the recess 13, and the chain line in FIG. As shown, the sphere 14 is located at the recess 15.
It protrudes and fits inside. When the disk 7 further rotates from this state, the sphere 14 is pushed into the depression 13 along the slope of the wall surface of the depression 15, and the reaction force against this pushing acts as a resistance force against the rotation of the winding shaft 4. , the winding shaft 4 rotates at a slow speed.

At a position away from the recess 15, the support hole 1
The spherical body 14 is supported by the inner surface of the winding shaft 2 and remains recessed in the recess 13, so that no large resistance force acts on the winding shaft 4.

In the illustrated embodiment, the disk 7 and the fixed plate 11 are provided with a plurality of spheres 14 and the same number of recesses 15, but it is not necessary to provide the same number of them, and one or both of them may be used as one. Good too. FIG. 4 shows a case in which three spheres 14 and one recess 15 are provided.

In addition, in the above embodiment, the insect screen door is opened and closed vertically, but it may be opened and closed left and right.The braking device of the present invention can also be applied to devices other than insect screens, such as insulating screens such as windows, refrigerators, etc. Needless to say, the present invention can also be applied to heat insulating membranes for housing cases.

As described above, according to the present invention, a sphere is provided on the outer circumferential surface of the rotary plate attached to the winding shaft, and the sphere is displaceable in the direction of centrifugal force by rotation, and the sphere is partially attached to the fixed plate attached to the winding box. A recess into which the winding shaft can be inserted is provided, and when the winding shaft is rotated, the disk is rotated while the sphere repeatedly protrudes into the recess and retreats into the recess. The reaction force when the sphere that has been fitted into the recess is pushed back into the recess acts as a resistance force against the rotation of the winding shaft, and this resistance force allows the screen to be wound up at a slow speed. Further, since it can be constructed from a simple fixing plate, a disk, and a sphere, the construction is very simple and it is easy to attach it to the roll-up screen.

[Brief explanation of the drawing]

FIG. 1 is a partial sectional view showing an embodiment of the present invention;
Figure 2 is a cross-sectional view taken along the line A-A, and Figure 3 is the cross-sectional view taken along line A-A.
FIG. 4 is a partially enlarged view of the figure and a sectional view at the same position as FIG. 2 showing another embodiment of the present invention. 1... Winding box, 4... Winding shaft, 7... Disc, 11... Fixed plate, 12... Support hole, 13...
Recess, 14... sphere, 15... recess, S... screen.

Claims (1)

[Scope of utility model registration request] A winding shaft driven by a spring force is provided inside the winding box, and the screen is automatically wound up by the winding shaft, and the fixing plate fixed to the winding box is supported. A disk attached to a winding shaft is rotatably fitted into the hole, and at least one depression is provided on the outer peripheral surface of the disk, and the disk can be displaced in the direction of centrifugal force by rotation of the disk inside the depression. At least one recess into which the sphere can fit is provided on the inner peripheral surface of the support hole in the fixing plate, and the recess on the outer peripheral surface of the disc is formed to a depth that allows the sphere to completely fit therein, and the support hole in the fixed plate is provided with at least one recess into which the sphere can fit. A braking device for a winding screen, characterized in that a concave portion on the inner peripheral surface of the hole is formed to be shallower than the diameter of the sphere.