JPS6258952B2 - - Google Patents

Description

[Detailed Description of the Invention] Stair-climbing hand carts for carrying luggage up the stairs of buildings are well known, and for example, a home appliance store or the like delivers the appliances to a purchaser's home. It is used for.

Some such carts have a pair of wheel-carrying frames in the shape of an equilateral triangle or three-star shape, with an end of a rotating shaft attached to each vertex of the frame. be. 1 like this
The paired wheel carrying frames are assembled in axial alignment to define three sides of the virtual prism and carry a set of three wheels or more than one set of wheels. Conventional push carts of this type are not propelled by power, and therefore have problems such as requiring a great deal of effort to use.

SUMMARY OF THE INVENTION The object of the invention is to provide an electric cart which can be electrically driven in a simple, economical and reliable manner to transport even very heavy loads. It is.

Another object of the invention is to electrically power the hand cart in such a way that it ensures stable use both when going up and down stairs and even when going down stairs fully loaded. It is to drive.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

Referring to FIGS. 1 and 2, the electric stair climbing hand cart of the present invention includes a pair of strong tubular members 1, 1 arranged parallel to each other and spaced apart from each other. It consists of a frame T consisting of transverse members 2, 2', 2'' interconnecting the tubular members 1 and 1. The sides of the tubular members 1, 1 which are connected by the transverse member 2' An upwardly protruding fork-like member 3 is fixed to the end of the tubular member 1. The fork-like member 3 is reinforced by an intermediate transverse member 4. terminating in a split tapered split 101 which serves as a clamp for inserting the first horizontal portion of the corresponding tubular member 6 into the tubular member 1; By elastically tightening the split portion 101 with the screw 5, the horizontal portion of the member 6 can be fixed in a position-adjustable manner.Each tubular member 6 is bent upward at a right angle from the first horizontal portion. a second intermediate portion 106 and a fork-like member 3 from the upper portion of the intermediate portion;
It has a third portion that is inclined toward and extends upwardly. A rubber grip 7 is provided in this third portion. At the upper end of one of the grips 7, a push button switch 8 is provided for activating an electric motor for driving the cart, which will be described later. The curved outer surface of each tubular member 6 between the first horizontal portion and the upright intermediate portion 106 can be used as an additional grip or as cart support legs when lowering the cart onto a staircase. The protruding member 9 is welded.

The stair climbing cart of the present invention is used by user Q in the manner shown in FIG.
By suitably adjusting the length of the horizontal portion of the tubular member 6, the frame T can be preset to receive loads Z of different sizes. The luggage Z to be carried along the stairs is placed on the frame T against the fork-shaped member 3,
1 secured to the tubular member 1 at a site 10;
The load can be secured to the frame T by means of one or more elastic straps A.

At the end of the fork-shaped member 3 of the cart, a pair of parallel trapezoidal right-angled frames 11 of the same size, one for each tubular member 1, are attached to the tubular members 1 at their longer bases. 1 is integrally fixed. An axle box 12 for rotatably supporting a shaft 13 of a wheel assembly, which will be described later, is fixed to the shorter bottom side of each trapezoidal frame 11 parallel to the frame T. Shaft 13 is drivingly connected to parallel shafts of electric motor and electromagnetic brake units 14-15. Units 14-15 are connected to the transverse member 2'
It is adjustably fixed to a bracket-like support 66 welded to the holder.

The drive connection between the units 14-15 and the shaft 13 is provided by toothed pulleys 16, 17 interconnected by a toothed belt 18, as shown in FIG.
This is achieved by a reduction gear drive mechanism consisting of pinion sets 19-20, 21-22 and 23-24 connected by chains 25, 26 and 27, respectively. Pulley 17 is coaxially fixed to pinion 19, pinion 20 is coaxially fixed to pinion 21, and pinion 22 is coaxially fixed to pinion 23. This pulley and pinion assembly 17-19, 22-23 is
It is rotatably mounted on a shaft 28 supported by one of the trapezoidal frames 11 and another frame (not shown) that is integrally attached to the tubular member 1 .

As shown in FIG. 3, pinion 20 is coaxially fixed to pinion 21, and this assembly 20-21 is fixed to shaft 13 for rotation therewith. A pinion 24 is keyed to the shaft 13.

The ratio of the diameters of pulleys 16 and 17 is, for example, 1:5.
The ratio of the diameters of pinions 19 and 20, 21 and 22, and 23 and 24 is 1:3. for example
A battery carrying frame for supporting a storage battery 29 capable of supplying 12V power is fixed to the tubular member 1. The accumulator 29 has a secondary battery to prevent liquid within the battery from leaking into the sealing plug 129 when the cart is in its normal use position.
It is tilted as shown in the figure.

A pair of equilateral triangular wheel support frames 30 are attached to both ends of the shaft 13 and are aligned in the axial direction so as to define each side of the virtual prism. 1 at each apex angle of these frames 30.
Three wheels 31 each having the same diameter are rotatably mounted.

Each triangular wheel carrying frame 30 is formed by a pair of parallel outer and inner plates;
The inner plate of at least one of the frames has three arcuate projections 32 formed concentrically with the shaft 13, corresponding to each wheel 31, as shown in FIG. When the shaft 13 is rotated, the protrusion 32
contacts a microswitch 33 fixed to one of the trapezoidal frames 11, whereby the rotation of the shaft 13 is sensed by the microswitch.

Referring to FIG. 2, the device of the invention comprises a tab 34 located on the underside of one of the tubular members 1 near the clamping end 101. The knob 34 is connected via a control rod 35 to
This is for remotely controlling an electric switch 36 located near the motor 14. A support member 59 fixed to the intermediate portion of the transverse member 2″ has a reference numeral 3.
A leg 37 is pivotally attached as shown at 8. The legs 37 can be fixed in a horizontal position, shown in solid lines in FIG. 2, or in a vertical position, shown in dotted lines, as desired. A mounting member 3 is attached to the middle part of the horizontal member 2'.
9 is fixed, and a plate 41 is pivotally attached to this mounting member as indicated by the reference numeral 40. Board 41
carries a caster wheel 42 and is moored to a tension spring 43 which holds the assembly 41-42 in the position shown in FIG. 2 and toward a neutral position during backward rotation. Being moved. Assemblies 41-42 are normally placed in a neutral position. The push button 8 is
It is connected via a helical cable 44 inserted into one of the units constituted by the tubular members 1 and 6 to an electrical circuit (FIG. 4) to be described below.

As shown in FIG. 1, the handcart of the present invention further includes a high impact plastic casing 45 for enclosing the entire drive mechanism and battery 29. This casing is provided with an opening for connecting a cable to a terminal of the battery 29 for charging. An indicator light 47 shown in FIG. 4 and a knob 46' for operating the rheostat 46 are attached to the upper part of the casing.

The electric circuit of this pushcart comprises two relays 48, 49 whose contacts are protected by capacitors 50, 51 with appropriate operating characteristics.

The operating mode of the hand cart for climbing stairs of the present invention is as follows. To prepare the cart for climbing the stairs S by rotating the shaft 13 in the direction of the arrow F ₁ , the changeover switch 36 is connected to the contact 13
6,236,336 are closed, contacts 436,53
6 to the open position. Thereby, the circuit of the electromagnetic brake 15 is closed via the push button 8 which is in the inoperative position shown in FIG. 4, so that the electromagnetic brake 15 is energized. Here, if the push button 8 is pressed down, the current to the brake 15 is cut off, and the relay 48 which is in charge of supplying power to the electric motor 14 is
is energized, thereby causing motor 14 to drive shaft 13 rotationally in the direction of arrow F ₁ (FIG. 1). Each time the operator releases the push button 8, the power supply to the motor 14 is stopped, the electromagnetic brake 15 is energized, and the 2
The shaft 13 is locked in any rotational position of the set of wheels 31. Once the cart reaches the stair landing, the cart can be operated with only two or one of each set of wheels resting on the floor. When operating with only one of the wheels in contact with the floor, the caster wheel 42 can be operated with the floor in contact, thereby allowing the cart to stand on its own in the transport position, so that the operator simply All you have to do is pull and guide the cart.

When the changeover switch 36 is operated and set to the state shown in FIG. 4, the contacts 136, 236, 3
36 is opened, contacts 436, 536 are closed, and the cart is brought to a ready state for descending the stairs. In this case as well, when the push button 8 is in its inoperative position, the electromagnetic brake 15 is activated and locks the shaft 13. While the operator continues to press the pushbutton 8, the current to the brake 15 is cut off, and the two states described below occur periodically, causing the shaft 13 to move as shown by the arrow in FIG.
Rotated in the direction indicated by F ₂ . That is,
Each time two wheels 31 of each set of wheels step on a respective step of the stairs S as shown in FIG.
The microswitch 33 is placed in a switched state relative to the state shown in FIG. The microswitch 33 therefore energizes the relay 48, which closes the power supply circuit to the motor 14 and the polarity of the battery 29 is reversed. When the shaft 13 is rotated beyond an imaginary vertical plane passing through the axis of the wheel 31 resting on the step tread, the micro switch 3
3 is returned to the state shown in FIG. 4 again to deenergize relay 48 and energize relay 49. Relay 49 cuts off power supply to motor 14 via rheostat 46 . During this phase, the action of the cart's load causes the shaft 13 to rotate in the direction F ₂ , with the deenergized motor 14 acting as a brake and appropriately slowing down the cart's downward movement. (brake) Therefore, rheostat 46
It is possible to adjust the lowering speed of the cart by controlling .

When the changeover switch 36 is in either of the two operating positions, the indicator light 47 is lit to indicate that the cart is in the energized state.
When the cart is not in use, transfer switch 36 must be in a neutral position opening contacts 136, 236, 436, 536. When contacts 136, 236, 436, 536 are opened, battery 29 is disconnected from the electrical circuit.
The indicator light 47 goes out, indicating that the cart is not in use.

[Brief explanation of the drawing]

FIG. 1 is a schematic perspective view showing an operator operating a hand cart of the present invention along stairs;
FIG. 2 is a partially sectional side view of the hand cart, FIG. 3 is a plan view of the reduction gear mechanism used in the cart of the present invention, and FIG. 4 is a schematic diagram showing the electric circuit of the cart of the present invention. FIG. 5 is a side view, partially in section, showing the wheel carrying frame of the cart of the present invention. In the figure, 7 is a grip, 8 is a push button switch,
13 is a shaft, 14 is a motor, 15 is an electromagnetic brake,
29 is a battery, 30 is a wheel support frame, 31 is a wheel, 36 is a changeover switch, and 46 is a rheostat.

Claims (1)

[Scope of Claims] 1. A shaft 13, a wheel carrying frame 30 fixed to each of the ends of the shaft, equidistant from the shaft, for transporting goods along a staircase. and two or more wheels 31 of the same diameter arranged at equal angular intervals and carried by the frame, wherein the shaft 13 is connected to a battery. Reduction gear mechanisms 16-17, 19-2 are connected to the unit of electric motor 14 and electromagnetic brake 15, which are supplied with power from 29 through an electric circuit.
0, 21-22, 23-24, the electrical circuit is operable to place the circuit in a first operating position for climbing the cart along a staircase, or for driving the cart up a staircase. a changeover switch 3 for setting a second operating position for lowering the battery along the line or a neutral position for cutting off current from the battery;
6 and a pushbutton switch 8 mounted on one of the grips 7 of the cart, which pushbutton switch 8 is activated when the changeover switch 36 is in either of its two operating positions. , when the electromagnetic brake 1 is in the inoperative position.
5 is closed to stop the shaft 13 at any angular position, and when the pushbutton switch is actuated, the power supply to the electromagnetic brake is cut off, preventing the cart from climbing. the angular position of the wheels in order to configure the circuit in such a way that a relay is energized for powering the motor directly in the case of movement and powering the motor in the case of downward movement of the cart; A detection device is provided for detecting a second one for lowering the cart, said detection device consisting of a micro-switch 33 for detecting a protrusion 32 provided on one of said wheel-carrying frames; When in the operating position, the detection device causes the motor to rotate in the required reverse direction until the shaft is rotated beyond an imaginary vertical plane passing through the axis of the wheel 31 resting on the floor. energizes the relay 48 to supply a polarized current, which then acts as a brake on the motor to slow down the latter part of the cart's downward movement, which is effected by the action of the weight of the cart; An electric hand cart, characterized in that the electric hand cart is configured to energize another relay 49 that short-circuits the motor. 2. A potentiometer or rheostat 46 is connected in series in the circuit to cause the motor to act as a brake, and by controlling the rheostat the speed of the downward movement of the cart is adjusted. The electric hand cart according to claim 1, wherein the electric hand cart is adapted to be able to perform the following functions. 3. An electric hand cart as claimed in claim 1 or 2, in which a capacitor is provided to be shunted to the relays to ensure a long service life of the relays. 4 The electromagnetic brake 15 is connected to the electric motor 1
4. The electric hand cart according to any one of claims 1 to 3, wherein the electric hand cart is connected to a stator of No. 4 and is configured to act directly on the shaft of the motor. 5. The reduction gear mechanism connecting the motor 14 to the shaft 13 includes a pinion and a chain,
The electric hand cart according to any one of claims 1 to 4, which can be combined with a toothed pulley and a toothed belt.