JPS6020524Y2 - Lifting device for auxiliary platform legs - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a safety device for an auxiliary platform lifting device in a tractor trailer or the like.

Usually, a tractor trailer is provided with auxiliary legs on both sides of the vehicle body at the front of the lower surface, and the legs are appropriately extended to lift the trailer from a normal position, thereby making it possible to separate the trailer and the tractor.

The present applicant previously proposed a drive device in which a motor was installed in parallel with a conventional manual lifting handle for raising and lowering the above-mentioned pedestal (Japanese Utility Model Publication No. 50-133611).

In this drive device, as shown in FIG. 2, the rotation of the motor 31 is transmitted to the lifting device 2 via the gear 33 on the rotating shaft 4, so when the motor 31 is driven, the rotating shaft 4 rotates at the same time. If the manual handle 42 is moved to the tip of the rotating shaft 4,
If the motor 31 were accidentally started with the motor inserted, the manual handle 42 would rotate at the same time, risking personal injury.

Purpose of the present invention The present invention is a trailer auxiliary leg lifting device that opens the electric circuit of the motor when a manual handle is attached to the auxiliary leg lifting device of a trailer, eliminating the risk of the motor rotating unexpectedly and improving safety. The purpose is to provide equipment.

The structure of the present invention has a rotating shaft 4 which is provided with a reduction gear 33 that connects the lifting device 2 of the auxiliary leg 1 and the drive motor 31, and has a mounting portion 43 at one end to which a manual handle 42 is removably attached.
An opening/closing plate 53 is provided near the mounting portion 43 of the shaft 4 to cover the tip of the shaft 4 in an openable/closing manner, and the opening/closing plate 53 is equipped with a switch 5 that opens the electric circuit of the motor 31 when the opening/closing plate is opened.
Connected 2.

Functions and Effects of the Present Invention When manually operating the lifting device 2 of the auxiliary platform leg 1, it is necessary to open the opening/closing plate 53, release the end attachment portion 43 of the rotating shaft 4, and attach the manual handle 42. Of course, when the opening/closing plate 53 is opened, the circuit of the motor 31 is opened, so there is no risk that the manual handle will be mistakenly rotated when the manual handle is attached, and the previous danger can be eliminated.

The present invention will be specifically described below based on embodiments shown in the drawings.

The auxiliary base leg 1 is attached to the trailer 1 as shown in FIGS. 1 and 2.
A pair of rectangular cylindrical fixing frames 11 each having an opening at the bottom are fixed on both sides of the front part of the frame 3. Inside the fixing frame 11, telescopic legs 12, which are open at the top and have a support part 17 at the lower end, are slid. By driving the elevating device 2 provided between the fixed frame 11 and the telescopic frame 12, the telescopic frame 12 is moved out and down from the fixed frame 11 toward the ground 15 as appropriate.

The lifting device 2 for the telescopic legs 12 has the upper end of the screw shaft 21 rotatably attached to the upper center of the fixed frame 11, and the lower end attached to the fixed frame 1.
1 to the vicinity of the lower edge 16.

A screw bush 22 is fixed to the center of the upper part of the telescopic leg 12 and is screwed into the screw shaft 21.

Further, above the screw bush 22, a saucer 23 is provided which is screwed onto the screw shaft 21, and grease 24 is normally stored on the saucer 23, and if necessary, the inside of the telescoping leg 12 is filled with oil. , to lubricate between the screw shaft 21 and the screw bush 22.

Further, the upper end of the screw shaft 21 is provided with a bevel gear 25, and by transmitting the rotation of the drive device 3 to the gear 25, the screw shaft 21 can be rotated in forward and reverse directions, and the screw bush 22 that is threaded with the screw shaft 21 can be moved up and down. and the telescopic legs 12 to which the bushings 22 are fixed are raised and lowered.

The drive device 3 connects the rotating shaft 32 of the motor 31 and the bevel gear 25 with three stages of reduction gears 33, 34, 35, and the reduction gear 33 adjacent to the motor 31 connects the rotating shaft 32 of the motor 31 with the bevel gear 25. One end thereof projects outward from the gear box 36, and an engagement pin 41 is provided projecting from the tip, thereby forming a mounting portion 43 for the manual handle 42.

The rotary shaft 4 is formed to be able to slide within a predetermined range in the axial direction, and when the rotary shaft 4 is pulled forward and the reduction gear is engaged, the manual handle 42 is fitted into the mounting portion 43, and the handle is removed as it is. 42, the rotation of the handle 42 is decelerated and transmitted to the screw shaft 21.

Also, if the rotating shaft 4 is pushed in, the reduction gear 33 is detached from the rotating shaft 32 of the motor 31 and becomes the small diameter gear 37 of the second reduction gear 34.
, the rotation of the handle 42 is accelerated and the lifting device 2
transmitted to.

Furthermore, a safety device 5 is provided near the attachment portion 43 at the tip of the rotating shaft 4 to detect insertion and removal of the manual handle 42 and stop the drive of the motor 31.

The safety device 5 is connected to the gear box 3 as shown in FIGS. 3 and 4.
A pedestal 51 extends parallel to the rotation axis 4 from the wall surface of the pedestal 5, and a limit switch 52 is provided on the pedestal 51.
An opening/closing plate 53 is pivotally supported at the tip of the opening/closing plate 53.

The opening/closing plate 53 has a plate shape with a cover wall 54 on one side and an abbreviated pushing plate 55 on the other side. By pivoting approximately the center to the frame 51, the tip 44 of the rotating shaft 4 is usually covered with a cover wall 54 to prevent the manual handle 42 from being attached, and the manual handle 42 is sometimes attached to the opening/closing plate 53.
By rotating the switch in the direction of arrow 56, the tip of the push plate 55 pushes the cutout 57 of the limit switch 52 and opens the drive circuit 6.

As shown in FIG.
On the other hand, they are detachably connected by a connector 62.

FIG. 5 shows an example of the drive circuit 6, and a lamp circuit 6 that is connected in parallel with the storage battery 61 to indicate automatic operation of the drive device 3, etc.
3 and the motor circuit 7 are connected.

The motor circuit 7 connects a reversibly rotatable DC motor 31 and a storage battery 61 via a double-throw switch 71, and makes it possible to reverse the direction of current flowing through the armature winding of the motor 31. The direction of rotation is reversed by changing the closing position of the switch 71.

Further, a regulation circuit 8 regulates the start/stop timing of the motor 31.

The regulation circuit 8 connects in parallel limit switches 81 and 82 that open when the upper and lower limits of the telescoping leg 12 are detected, and further connects an electromagnetic relay 83 in series with the limit switch 52 of the safety device 5. A normally open contact 84 is interposed in the motor circuit 7, and each limit switch 8
1. 82. In conjunction with the detection operation of 52, electromagnetic relay 8
3 is turned off, contact 84 is opened, and motor 31 is stopped.

Note that the safety device 5 is not limited to the above embodiment,
Of course, as long as there is a device that can detect the attachment of the manual handle 42 and stop the motor 31, the configuration, mounting position, etc. can be changed as appropriate.

6 and 7 show other embodiments of the safety device 5, in which a pedestal 91 is attached to the wall of the gear box 36, and a cylindrical switch shaft is mounted on the pedestal 91 in parallel with the rotating shaft 4. 92
is rotatably provided, and the shaft 92 has an opening/closing plate 53 projecting from the tip thereof perpendicularly to the shaft 92.

The limit switch 52 is fixed onto the pedestal 91 with the cut piece 57 facing the circumferential surface 94 of the switch shaft 92.

Furthermore, when the tip of the rotating shaft 4 is covered with the opening/closing plate 53, the section 57
When the manual handle 42 is installed, the switch shaft 92 is rotated from its normal position and the circumferential surface 94 pushes the cutout 57 to open the limit switch 52 and stop the motor 31. let

As described above, the present invention is configured to stop power supply to the motor 31 when the manual handle 42 is attached to the rotating shaft 4, so even if the power switch is accidentally turned on during manual operation, the motor 31 will continue to operate. This has an excellent effect of preventing accidents caused by automatic rotation of the manual handle 42 without operating.

[Brief explanation of the drawing]

Figure 1 is a front view showing a trailer equipped with legs, Figure 2 is an enlarged sectional view with a part of the legs broken away, Figure 3 is a front view of the lifting device, and Figure 4 is Figure 3. A sectional view taken along the line IV-IV, FIG. 5 is an electric circuit diagram, and FIGS. 6 and 7 are other embodiments of the safety device. 1... Auxiliary platform leg, 2... Lifting device, 3
... Drive device, 4 ... Rotating shaft, 42.
...Manual handle, 5...Safety device.

Claims (1)

[Scope of utility model registration request] The elevating device 2 of the auxiliary platform leg 1 to be disposed on the vehicle body and the drive motor 31 are connected via a reduction gear 33, and one end of the rotating shaft 4 provided with the reduction gear 33 is extended outwardly. In the drive device 3, which includes a mounting portion 43 for removably attaching a manual handle 42 to the tip of the rotating shaft 4, the rotating shaft 4
An opening/closing plate 53 is provided near the manual handle mounting portion 43 to cover the tip of the rotary shaft 4 in an openable/closing manner, and the opening/closing plate 53 is equipped with a switch 52 that opens the electric circuit of the motor 31 when the opening/closing plate is opened. Lifting device for connected auxiliary platform legs.