JPH0537813Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a wire slack detection device for an electric lift bed, which can be stored in the ceiling by winding up the wire when not in use.

[Prior Art and Problems to be Solved by the Invention] Some electric lift beds of this type include four wires stretched between the bed frame and a guide rail that guides the bed frame to support the bed frame. Some devices are constructed so that the wire is wound up and unwound onto a wire drum provided on the bed frame side, and is guided within a guide rail to move up and down.
In this case, when the bed is lowered, the lowering is restricted when it reaches a predetermined position and touches a stopper, or when it touches some kind of obstacle.
A wire slack detection device is provided that detects loosening of the wire and automatically stops motor drive. However, conventional wire slack detection devices can only detect the slack of one wire.
For this reason, it is necessary to install four wire slack detection devices in the bed, which is not only troublesome to assemble, but also increases costs, so improvements are desired.

[Means for Solving the Problems] In view of the above-mentioned circumstances, the present invention has been devised for the purpose of providing a slack detection device for an electric lift bed that can eliminate these drawbacks. A wire is stretched between the bed frame and the guide rail that guides this corner,
In an electric lifting bed that moves up and down as the wire is wound around a drive-side wire drum, a pair of wire guides that guide the wire toward the drive drum are moved away from each other when the wire is in a tensioned state. On the other hand, between the wire guides, an energized bomb is inserted so that the wires move toward each other when they become slack, The present invention is characterized by providing a slack detection means for detecting wire slack based on separation.

With this configuration, the present invention enables one detection device to detect the slack in each of the two wires.

[Example] Next, an example of the present invention will be described based on the drawings. In the drawings, reference numeral 1 denotes a bed frame of an electrically-operated elevating bed, and an operating shaft 2 is rotatably supported on the upper surface of a substantially central portion of the floor surface of the bed frame 1 in a front-rear direction. A driven sprocket 3 and four wire drums 4 of the same diameter are integrally attached to this operating shaft 2 in pairs, two for the left wire and two for the right wire. A transmission chain 7 is suspended between the electric motor 5 and the drive sprocket 6 provided on the bed frame, and the driving shaft 2 is connected to the forward and reverse rotation of the electric motor 5.
By rotating the wire drum 4 together, four wires 8, which will be described later, are wound around the wire drum 4 and unwound. Further, guide bodies 9 are integrally provided at the four corners of the bed frame 1, and the guide bodies 9 are guided by guide rails 10 laid between the ceiling and the floor. One end of the wire 8 is fixed to the upper part of the guide rail 10.
is connected to the wire drum 4 via the guide rail 10, the guide body 9, and the side edge of the bed frame, so that the bed frame 1 can be attached to the guide rail 10 while being suspended by the four wires 8. It is designed to move up and down in parallel while maintaining a horizontal posture.

Wire slack detection device 11 in which the present invention is implemented at two locations on the tensioning route of the wire 8 configured as described above.
is provided, which detects if any one of the four wires 8 is loosened,
The drive of the electric motor 5 is automatically stopped. That is, the wire slack detection devices 11 are respectively attached to the left and right side plates 1a of the bed frame 1, and one of them will now be explained. Reference numeral 12 denotes a mounting bracket provided on the side plate 1a of the bed frame 1, which is screwed and fixed to the side plate 1a and reinforcing plate 1b of the bed frame. is provided. On the floor side of the support plate 12a, a pair of rocking plates 13, 14 are pivoted at one end by pivots 13a, 14a so that they are located in parallel in the front and back. A predetermined interval is provided between them so that they can swing freely about pivots 13a and 14a, respectively. Pulleys 15 and 16 are provided on the other end sides of the swing plates 13 and 14.
are rotatably provided via support shafts 15a and 16a, thereby configuring the wire guide according to the present invention.A bullet 17 is interposed between support shafts 15a and 16a. Cage, pulley 15, 16
together with the swing plates 13 and 14, the pivots 13a and 14a
It is constantly biased in the direction of approach using the fulcrum as the fulcrum.
The wire 8 drawn in from both the front and rear sides passes through pulleys 15 and 16 to the wire drum 4.
It is wired so that it is wrapped around the

On the other hand, 18 and 19 are detection switches installed opposite to the swing plates 13 and 14, and when the wire 8 is under tension due to the weight of the bed frame 1, the swing plates 13 and 14 are activated. The pulleys 15 and 16 swing in the opposite direction to separate from each other against the urging force of the machine 17, and as a result, the switch contacts of the detection switches 18 and 19 are pressed and turned OFF (looseness is not detected). The downward drive of the electric motor 5 is maintained continuously. In addition, if at least one wire 8 becomes loose for some reason, the swing plate 1
3 and 14 swing in the approaching direction under the urging force of the ammunition 17, thereby causing the detection switches 18 and 19 to be activated.
Since the rocking plates 13 and 14 are no longer in contact with the
Detection switches 18 and 19 are ON (looseness detection state)
As a result, the downward drive of the electric motor 5 is stopped.

In the embodiment of the present invention constructed as described above, when the bed frame 1 descends to a predetermined position and comes into contact with the stopper 20, of course,
Even if an obstacle is encountered at the stage of lowering the bed higher than that, the wire slack detection device 11 will reliably detect this and the lowering operation of the bed frame will be stopped.

That is, if the wire 8 becomes slack during the lowering operation of the bed frame 1, the swing plates 13 and 14, which have been receiving the tension force of the wire 8 and swinging outward against the bomb 17, will The bomb moves inward due to the biasing force of the bomb 17, and as a result, the detection switches 18 and 19
is turned ON when the pressing contact from the swing plates 13 and 14 is removed, and slackness of the wire 8 is detected, thereby stopping the drive of the electric motor 5.

As described above, in this embodiment, the wire slack detection device 11 immediately detects when at least one of the two wires 8 of the bed pedestal 1 is loosened, and therefore, the wire slack detection device 11 immediately detects this when at least one of the two wires 8 of the bed mount 1 is loosened. 8 required a dedicated wire slack detection device 11, whereas the structure of the detection device is simplified, parts can be used interchangeably, the number of parts can be reduced, and manufacturing can be done at low cost.

As shown in FIG. 5, stoppers 13b and 14b are provided on the opposing inner sides of the swing plates 13 and 14, and a detection switch 20 is further provided on the inner side of one of the swing plates 14 to ensure that the wire 8 The detection switch 20 may be configured to turn on when the wire 8 is loosened and the rocking plates 13 and 14 move inward, thereby detecting the slack in the wire 8 and thereby stopping the drive of the electric motor 5. With this configuration,
Only one detection switch 20 needs to be provided, and the number of parts can be further reduced.

[Operation and Effect] In summary, the present invention is constructed as described above, and when detecting the slackness of the wire, the wire guide is moved from the separated state to the close position by the action of the bullet interposed between the two wire guides. When the detection means detects this, the slackness of the wire is detected. Therefore, there is no need to provide a dedicated wire slack detection device for each wire as in the past, and the slack detection of a pair of wires can be accomplished by using a common member such as a bullet.
As a result, the number of parts can be reduced, and a significant cost reduction can be expected.

[Brief explanation of the drawing]

The drawings show an embodiment of the wire slack detection device for an electrically-operated elevating bed according to the present invention, in which Fig. 1 is an overall perspective view of the electrically-operated elevating bed, and Fig. 2 is an overall plan view of the bed frame. 3 are plan views of essential parts, FIG. 4 is an overall plan view of a bed frame showing a conventional example, and FIG. 5 is a plan view of main parts showing a second embodiment. In the figure, 4 is a wire drum, 5 is a motor, 8 is a wire, 11 is a wire slack detection device, 13 and 14 are rocking plates, 15 and 16 are pulleys, 17 is a bullet, 1
8 and 19 are detection switches.

Claims (1)

[Scope of utility model registration request] A wire is stretched between the bed frame and a guide rail that guides the corner portion, and the wire is driven by an electric elevating bed that is raised and lowered by being wound around a wire drum on the drive side. A pair of wire guides that guide the drum side are movably arranged opposite each other so that they move away from each other when the wire is in a tensioned state, while a pair of wire guides is provided between the wire guides so that they move toward each other when the wire is in a slack state. Interpose energized ammunition to move it to the side,
A wire slack detection device for an electrically operated elevating bed, further comprising a slack detection means for detecting wire slack based on movement of both wire guides toward and away from each other.