JPH06158890A - Pallet drop preventing dc solenoid for lift type parking device - Google Patents

Abstract

PURPOSE:To thaw the frozen part of a pallet drop preventing stopper or prevent the stopper from freezing. CONSTITUTION:When a stopper 22 is frozen, an AC voltage is applied to a DC/AC common coil (AC voltage applying coil) 18 of a DC solenoid 10 to produce heat due to iron loss in a plunger 14, and the heat is transferred to a stopper 22 to thaw the frozen part and bring the stopper 22 back to the operating condition. Then a DC voltage is applied to the DC/AC common coil 18 and DC-exclusive coil 19 to move the stopper 22 backward by the magnetic attractive force between the plunger 14 and a core 16. Also, when the AC voltage is applied continuously to the DC/AC common coil 18, the stopper 22 is prevented from freezing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solenoid for actuating a stopper for preventing a pallet from dropping in a lift type parking apparatus.

[0002]

2. Description of the Related Art In an elevating type parking device, in order to prevent the pallet from dropping when the chain or wire for lifting the pallet is cut or the hydraulic cylinder for raising or lowering causes oil leakage, the pallet is raised or lowered. Occasionally, the solenoid retracts the plunger by retracting it to retract it from the pallet hoistway.When the pallet is stopped, the solenoid is deenergized and the spring force causes the plunger to move forward to project the stopper into the pallet hoistway. It is used.

In this type of solenoid,
In order to prevent noise from being generated by collision with the core when the plunger is attracted by excitation, a gap is created between the plunger and the core even if the plunger is attracted by an elastic body such as rubber. However, if an AC voltage is applied to the solenoid that creates a gap between the plunger and the core, heat is generated due to eddy current loss and hysteresis loss (hereinafter referred to as iron loss). A solenoid is used.

[0004]

However, since this type of solenoid is often installed outdoors, the stopper may freeze in the guide during the winter, and even if the DC solenoid is excited, it may not operate. .

[0005]

As a means for solving the above problems, the first invention is, as described in claim 1, provided with a coil for applying an alternating voltage to a direct current solenoid, and for applying the alternating voltage. The configuration is such that the heat due to the iron loss generated in the plunger by the application of the AC voltage to the coil is transferred to the stopper.

According to a second aspect of the present invention, as described in claim 2, the AC voltage is temporarily applied immediately before the DC voltage is applied to the DC solenoid, or the DC voltage is applied to the DC solenoid. Prior to the above, a switch was provided to keep the AC voltage applied for a predetermined time.

[0007]

In the first aspect of the present invention, when the DC solenoid is excited, the plunger and the core are separated from each other. Therefore, when an AC voltage is applied to the AC voltage applying coil, heat is generated due to iron loss in the plunger, and the heat is generated. It is transmitted from the plunger to the stopper and the stopper is heated.If the stopper is frozen, the frozen part is melted and the stopper can be operated.If the stopper is not frozen, the stopper is frozen. It is prevented and the operable state is maintained.

After stopping the application of the AC voltage,
When a DC voltage is applied to excite the DC solenoid, the plunger retracts and the stopper retracts from the pallet lift passage.

In the second invention, the DC voltage is applied by the operation of the switch immediately after the temporary application of the AC voltage to the DC solenoid or after the application of the AC voltage for a predetermined time to the DC solenoid. The DC solenoid is excited.

While the AC voltage is applied, the heat due to iron loss generated in the plunger is transferred to the stopper and the stopper is heated, so that the frozen portion of the stopper is melted or the stopper is prevented from freezing. To be done.

Therefore, when the DC voltage is applied after the AC voltage is applied, the stopper is in an operable state, and when the DC solenoid is excited by the application of the DC voltage, the plunger retracts and the stopper moves up and down the pallet. Evacuate from.

Since the power consumption is extremely small when an AC voltage having the same voltage as the DC rated voltage is applied to the DC solenoid as it is, the AC voltage applied is used to melt the frozen portion or prevent the frozen portion. High value to generate sufficient heat energy.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings. In the two long side frames 3a, 3a of the rectangular frame 3 whose four corners are supported by the columns 2, there are provided two chains 4 which are respectively hung around a sprocket (not shown) which is rotationally driven by a motor 7. Books are arranged one by one. These four chains 4 hang down below the frame 3 by the same length, and the hanging bottom ends of both ends of both long sides of a rectangular pallet 5 for mounting an unillustrated automobile. The hanging metal fitting 6 fixedly attached to is connected.

When the button of the operation box 9 attached to the column 2 is operated in the elevator parking apparatus 1 having the above-mentioned structure, the four chains 4 are moved by the same length by the driving of the motor 7, The pallet 5 is a descent position shown by a chain line in Fig. 1 so that a car can be placed on the pallet 5 on the road surface, and a space is provided below the pallet 5 so that another car can be parked by a solid line in Fig. 1. It is adapted to be lifted and lowered in a horizontal posture between the lifted position shown.

Next, a means for preventing the pallet 5 from falling while the pallet 5 is in the raised position shown by the solid line in FIG. 1 will be described.

Four brackets 8 are fixed to the frame 3 so that the hanging metal fittings 6 are adjacent to each other when the pallet 5 is in the raised position.
The DC solenoid 10 is fixed to each of them so as not to interfere with the hanging metal fitting 6.

The DC solenoid 10 includes a solenoid body 13 fixed in a housing 12 and a solenoid body 13
And a plunger 14 made of a magnetic metal material that is fitted to the front end surface of the housing 12 and is fitted freely in the horizontal direction, and is attached to the opening of the front end of the housing 12 with a cylindrical flange. It is attached by fitting the body 11 into the attachment hole 15 of the bracket 8.

The solenoid main body 13 includes a core 16 and a coil bobbin 17, and is connected in series and has a DC / AC combined coil (corresponding to an AC voltage applying coil which is a constituent of the present invention) 18 and a DC dedicated coil 19 It is composed by. In the coil bobbin 17, a state shown by a solid line in FIG. 4 in which an AC voltage is applied only to the DC / AC combined coil 18 and a chain line in FIG. 4 in which a DC voltage is applied to the DC / AC combined coil 18 and the DC only coil 19 are shown. A switching circuit 20 including switching switches (corresponding to the switches which are the constituent elements of the present invention) 21 and 21 for switching to the state shown in is attached.

Switching circuit 20 for each DC solenoid 10
Is connected to an operation box 9 and an AC power supply (not shown), and the power source button of the operation box 9 is pressed to switch the switching circuit 2
With the power switch 30 of 0 closed,
When the AC voltage application button of the operation box 9 is pressed, the AC voltage is applied only to the DC / AC coil 18 by the operation of the switching switch 21, and the DC voltage application button of the operation box 9 is pressed. Then, the switching switch 21 is switched so that the DC voltage is applied to both the DC / AC combined coil 18 and the DC only coil 19.

At the tip of the plunger 14, a rod-shaped stopper 22 made of a material having excellent heat conductivity is connected.
Are fixed so that they can move horizontally together. On the other hand, a cylindrical heat insulating material 24 is provided on the hollow inner circumference of the mounting body 11.
Is fixed, and a slide guide tube 25 is fixed to the inner circumference of the heat insulating material 24. The stopper is slidably fitted in the sliding guide tube 25, and moves between the position where the tip of the stopper projects into the ascending / descending passage of the hanging metal fitting 6 of the pallet 5 and the position where it is retracted to the outside of the ascending / descending passage. It is about to do.

A compression coil spring (corresponding to a spring which is a component of the present invention) is provided between the rear surface of the mounting plate 26 sandwiched between the plunger 14 and the stopper 22 and the front end surface of the plunger body 13. 27 is attached, and the elastic force of the compression coil spring 27 urges the plunger 14 and the stopper 22 in a direction in which the tip end of the stopper 22 is projected into the lifting passage of the suspension fitting 6 of the pallet 5.

The DC solenoid 10 is not energized at all times, and the plunger 1 is biased by the compression coil spring 27.
4, the stopper 22 is held in a state in which the tip of the stopper 22 projects into the ascending / descending path of the hanging metal fitting 6 of the pallet 5, and when the pallet 5 is in the raised position shown by the solid line in FIG. The tip of the stopper 22 is inserted into the portion 28, and the pallet 5 is cut by cutting the chain 4.
When the support 5 is no longer supported, the upper back surface of the notch 28 is hooked on the upper surface of the stopper 22 so that the pallet 5
It has become possible to prevent the fall.

When a DC voltage is applied to the DC / AC combined coil 18 and the DC only coil 19 to excite them in such a non-energized state, the plunger 14 is applied to the core 16 by the magnetic attraction force against the bias of the compression coil spring 27. As shown by the chain line in FIG.
It is held in a state of not contacting the core 16 at the retracted position where it comes into contact with the tip end surface of the stopper 22, and the tip of the stopper 22 is retracted from the ascending / descending passage of the hanging fitting 6 so that the ascending / descending of the pallet 5 is not hindered. .

Similarly, when an AC voltage is applied to only the DC / AC dual-purpose coil 18 in the non-energized state to excite the coil 18, heat is generated in the plunger 14 due to iron loss.

Next, the operation of this embodiment will be described. The plunger 14 of the DC solenoid 10 freezes with its tip protruding into the ascending / descending path of the hanging bracket 6 of the pallet 5, and cannot move in the backward direction due to the magnetic attraction force when a normal DC voltage is applied. In the case of touching, first, the button for AC voltage application of the operation box 9 is operated to switch the switch 21.
Is applied to apply an AC voltage only to the DC / AC combined coil 18, causing the plunger 14 to generate heat due to iron loss.

The heat generated by the iron loss is transmitted to the stopper 22 by being transmitted through the plunger 14. Since the heat insulating material 24 is provided on the outer periphery of the slide guide tube 25 in which the stopper 22 is fitted, the heat transferred to the stopper 22 is hardly transferred to the mounting body 11, and the temperature of the stopper 22 rises. Thaw the frozen part. As a result, the stopper 22 can be moved in the backward direction by the magnetic attraction force when a normal DC voltage is applied.

Here, it is desirable that the time for applying the AC voltage be within a range such that the rising temperature of the DC / AC coil 18 does not exceed its allowable heat resistance temperature.

After that, by operating the DC voltage application button of the operation box 9, a DC voltage is applied to the DC / AC dual-purpose coil 18 and the DC dedicated coil 19 to be excited.
The magnetic attraction force generated by this excitation causes the plunger 14 together with the stopper 22 to be pulled back to the core 16 against the bias of the compression coil spring 27, and the tip end of the stopper 22 of the hanging bracket 6 of the pallet 5 is pulled. Evacuate outside the hoistway.

In the present embodiment, the button of the operation box 9 is manually operated to switch the switch 21 from the state in which the AC voltage is applied to the DC solenoid 10 to the state in which the DC voltage is applied. Instead of this, a control circuit for automatically switching the switching switch is provided, and the AC voltage is applied, the application is canceled, and the DC voltage is applied by switching the switching switch by performing a single button operation. May be automatically performed.

In another embodiment, even when the pallet is not moved up and down, the AC voltage is continuously or continuously applied to the DC / AC combined coil 18 within a range in which the temperature rise of the DC / AC combined coil 18 does not exceed the heat-resistant allowable temperature. The application may be continued intermittently.

In this case, the heat generated in the plunger 14 by the application of the AC voltage and transferred to the stopper 22 keeps the stopper 22 heated to a temperature at which it does not freeze. Freezing is prevented in advance, and the stopper 22 is always kept in an operable state.

When the stopper 22 is operated, the DC voltage application button of the operation box 9 is operated to change the DC voltage to the DC / AC dual-purpose coil 18 and the DC-only coil 19.
, The plunger 22 is attracted to the core 16 and the stopper 22 is retracted to the outside of the lifting passage of the hanging metal fitting 6 of the pallet 5.

After this, when the lifting and lowering of the pallet 5 is completed,
By operating the AC voltage application button of the operation box 9, the AC voltage is again applied to the DC / AC dual-purpose coil 18 so that the stopper 22 is prevented from freezing.

In this embodiment, the case where the invention is applied to the elevating type parking apparatus 1 using the chain 4 as a means for supporting the pallet 5 is explained, but the present invention uses other means such as a wire or a hydraulic cylinder. It can also be applied to a lift type parking device that is used to support a pallet.

[0035]

As has been made clear by the above description, the present invention prevents the frozen stopper from being melted or prevented from freezing due to the heat energy generated by iron loss in the plunger. Therefore, it is possible to prevent malfunction of the stopper due to freezing, and it is possible to maintain reliable operation even in cold regions.

[Brief description of drawings]

FIG. 1 is a perspective view of a lift-type parking device.

FIG. 2 is a partially enlarged perspective view showing a pallet falling prevention means.

FIG. 3 is a partially cutaway enlarged side view of a solenoid.

FIG. 4 is a configuration diagram of a switching circuit.

[Explanation of symbols]

1: Elevating type parking device 5: Pallet 10: DC solenoid 14: Plunger 18: DC / AC coil (coil for AC voltage application) 19: DC coil 2
1: Switching switch (switch) 22: Stopper
27: Compression coil spring (spring)

Claims (2)

[Claims] 1. When the pallet is moved up and down, the plunger is retracted by excitation to retract the stopper from the lift passage of the pallet. When the pallet is stopped, the excitation is released and the elastic force of a spring moves the plunger forward to move the stopper. In a pallet fall prevention DC solenoid of a lift type parking device that is made to project into the lift passage of the pallet, an AC voltage applying coil is provided in the DC solenoid, and an AC voltage is applied to the AC voltage applying coil. A direct current solenoid for preventing falling of a pallet in a lift type parking device, characterized in that heat due to iron loss generated in the plunger is transferred to the stopper. 2. When the pallet is moved up and down, the plunger is retracted by excitation to retract the stopper from the lift passage of the pallet, and when the pallet is stopped, the excitation is released and the elastic force of the spring advances the plunger to advance the stopper. In a pallet falling prevention DC solenoid of a lift type parking device that is made to project into the lift passage of the pallet, an AC voltage is temporarily applied immediately before the DC voltage is applied to the DC solenoid, or the DC solenoid is applied to the DC solenoid. A direct current solenoid for preventing falling of a pallet in a lift type parking device, which is provided with a switch for applying an alternating current voltage for a predetermined time prior to applying the direct current voltage.