JPS6230835Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in the structure of a manually operated lift-type load carrier, typically a pallet truck.

A manually operated pallet truck of the conventional jack-operated type is structurally a three-point grounding type in which wheels are essentially provided at three locations; These levers were designed to swing around the base fulcrum of the support levers to change the angle with respect to the floor (wheel contact surface), resulting in a lack of stability and a high load. However, there was a high risk of tipping over, and the cargo carrying capacity was poor.

The present invention solves these drawbacks by adopting a four-point grounding type with wheels installed at four locations, and improving the lift structure that moves the cargo receiving cart up and down to improve stability and increase load carrying capacity. The purpose of this invention is to provide a structure of a lift-type cargo carrier that is particularly advantageous when applied to manually operated pallet trucks. and a lift truck portion having a lift jack and wheels, wherein a receiving member portion provided at a predetermined portion of the load receiving truck portion is placed on a lift operating member of the lift jack. The load receiving truck section and the lift truck section are connected to each other by at least two upper and lower parallel link levers of equal length, and at least one of the link levers is provided with a load receiving truck section. This is because the levers for vertically operating the wheels of the truck are interlocked.

An embodiment in which the present invention is applied to a manually operated pallet truck will be described below with reference to the drawings.

In the illustrated pallet truck, the receiving truck portion is generally designated by the symbol A, and the lift truck portion disposed on the rear side is generally designated by the symbol B.

The cargo-receiving truck section A includes a box-shaped frame section 1 formed at the rear, and two left and right forks that serve as a cargo-receiving platform and extend horizontally forward from the lower part of the frame section 1 on the left and right for lifting and placing pallets. 2, and wheels 3, 3 are provided at the lower part of each of the fork parts 2, 2 near the tip thereof. Above frame part 1
consists of a pair of left and right side plates 4, 4 erected from the rear ends of both fork parts 2, 2, a front plate 5 stretched in front of the side plates 4, 4, and a horizontal plate 5, which constitutes a top plate stretched above these. It is formed into an arched box shape with a flat receiving member portion 6 and an opening on the rear side. A handle 7 for pulling and pushing the truck is provided on the upper part of the frame portion 1 and protrudes toward the rear side.

The left and right wheels 3, 3 provided on the both fork parts 2, 2 are respectively constructed in a front and rear double shape, and each is rotatably pivoted to the fork parts 2, 2 with a support shaft 8, 8. It is attached to the tip of bell crank type vertical operating levers 9, 9. As a result, both wheels 3, 3 can be moved up and down relative to the fork parts 2, 2 by rotation about the support shafts 8, 8 of the levers 9, 9, respectively. There is.

On the other hand, the lift truck section B includes a horizontal flat plate-shaped pedestal 10 whose width is slightly narrower than the opposing interval between the left and right side plates 4, 4 in the frame section of the load receiving truck section.
and a jack holding frame 11 integrally installed on the center of this frame 10, and a pair of left and right wheels 12,
12 are attached at intervals on the left and right sides of the lower part of the pedestal 10, and a lift jack 13 is fixedly housed and installed in the holding frame 11.

Wheels 12, 12 attached to the left and right sides of the pedestal 10
are independently vertically vertical pivot shafts 14,
14 to be rotatably attached to the frame 10, and in addition, the respective wheel rotation core shafts 15, 15 can be attached to the pivot shafts 14, 14 without setting them directly below the pivot shafts 14, 14. It is set in a prostrate position. That is, those left and right wheels 12,
Each of the trucks 12 can independently turn around the respective turning spindles 14, 14 in accordance with the traveling direction of the truck and change its direction in the traveling direction, thereby changing the traveling direction of the truck. It is configured as a so-called caster for snake operation, which can be freely controlled by pushing or pulling.

The lift jack 13 is configured with a suitable jack such as a hydraulic type, and has a lift operating handle lever 16 that projects rearward from the holding frame 11, and a lift operating member 17 that is a ram thereof.
is projected upward from the holding frame 11. At the upper end of the lift operating member 17, a roller 18 made of a roller or the like facing in the front-rear direction of the track is provided.
is made to be freely slidable in the front and back direction with respect to the lift jack 13.

The cargo receiving truck section A and the lifting truck section B configured as described above are located inside the frame section 1 of the former so that the latter faces from the rear side, and the lift operating member 17 of the jack 13 of the latter is positioned so that the latter faces from the rear side. The upper end, and therefore the rolling element 18, is connected to the receiving member portion 6 of the latter frame portion 1.
It is placed in contact with the part from below. As a result, the cargo receiving truck section A is supported by placing the receiving member 6 of the frame section 1 on the lift operating member 17 of the jack 13 of the lifting truck section B, and the contact portion of the support. The presence of the rolling element 18 allows the track to slide smoothly in the longitudinal direction between the receiving member 6 and the lift actuating member 17 at the contact portion thereof.

The frame portion 1 of the cargo receiving truck portion A and the lift truck portion B are connected by two parallel upper and lower link levers 20 and 21 of equal length, specifically as follows.

That is, between the left and right side plates 4, 4 of the frame part 1 of the load-receiving truck part A, two horizontal and parallel support shafts 22, 23 are installed at a distance from each other. On the upper support shaft 22 of the two, the bases of a pair of left and right upper link levers 20, 20 of equal length integrally projecting forward as shown in FIG. 5 are pivotally connected. The tips of the levers 20, 20 are pivotally attached to both sides of the jack holding frame 11 of the lift truck part B with support shafts 24, 24. In the same way, the lower support shaft 23 of the two is also attached to the upper link lever 20, 20 with an integral equal length extending forward as shown in FIG. The bases of a pair of left and right lower link levers 21, 21 are pivotally connected, and the tips of these link levers 21, 21 are pivotally connected to both sides of the pedestal 10 of the lift truck section B with support shafts 25, 25. be. In this way, when viewed from the side, the distance between the front and rear support shafts 22 and 24 of the upper link lever 20 and the lower link lever 2
1, the distance between the front and rear support shafts 23 and 25 of The distance between the support shafts 24 and 25 is set to be the same length.

Furthermore, a pair of left and right lower link levers 21, 2
As shown in FIG. 6, each of the levers 1 is of a bell crank type having another lever 26, 26 integrally projecting downward from its base around a pivot point to a support shaft 23. , the tips of the levers 26, 26 projecting downward are placed along the lower side of the fork parts 2, 2 with respect to the levers 9, 9 for vertical operation of the wheels 3, 3 provided on the fork parts 2, 2, respectively. They are connected and interlocked via extending connecting rods 27, 27.

Next, to describe its operation, as shown in FIG. 3, when the lift operating member 17 of the jack 13 is in the lowered state, the front wheels 3,3
and the pair of left and right rear wheels 12, 12 provided on the lift truck part B are in contact with the floor surface F at four points, and the fork parts 2, 2 are horizontally low parallel to the floor surface F. It's in a depressed state. Therefore, in this state, the truck can be rolled and moved on the floor surface F by pushing or pulling the handle 7, and the fork portion 2, 2 can be inserted or removed.

Next, as shown in FIG. 4, operate the handle lever 16 of the jack 13 to lift the lift operating member 17.
When the receiving member portion 6 is lifted, the portion of the receiving member portion 6 is lifted. Then, as the frame portion 1 is lifted, the pair of upper link levers 20, 2
0 and the pair of lower link levers 21, 21 simultaneously swing upward about the pivot shafts 24, 24 and 25, 25, respectively, which are connected to the lift truck part B. At this time, those upper link levers 2
0, 20 and the lower link levers 21, 21 are parallel and have the same length, the cargo receiving truck section A and the lift truck section B can operate the lift without causing any change in the connection angle between them. A slight sliding movement in the front and rear direction occurs at the support contact portion between the member 17 and the receiving member 6. At this time, a slight movement away from or towards the front and rear of the sliding portion, that is, a change in the connection interval, is absorbed by the movement of the rotor 18 in the front and back direction, so that the lifting jack 13 A large torque is not applied to the lift operating member 17, etc. in the horizontal direction. Along with this, the lower link levers 21, 21
As the levers 26, 26, which are integral with the frame portion 1, swing downward about the pivot shaft 23, the levers 26, 26, which are integral with the frame portion 1, swing forward about the pivot shaft 23, causing the connecting rod 27 to move forward. This will lead to a push towards As a result, the levers 9, 9 for vertically operating the wheels of the fork parts 2, 2 are rotated downward around their support shafts 8, 8, and the wheels 3, 3 attached thereto are operated to lift downwards. It will be lowered by the same amount as the lift amount of the member 17. Therefore, the fork parts 2, 2 are lifted in a horizontal state parallel to the floor surface F, and the loaded pallet can be lifted and transported to a desired location.

In this way, according to this configuration, when the jack 13 performs a lift operation, the cargo receiving truck section A and the lifting truck section B can be connected to each other by only slightly changing the connection interval between them. The angle does not change at all. Therefore, the lift truck part B is tilted with respect to the floor surface F and is always kept in a constant posture without changing its angle, and the wheels 12, 12 provided thereon do not change the angle with respect to the floor surface F. It is. As a result, the lift truck part B
Even if the wheels 12, 12 are configured as casters for steering the snake, the angle with respect to the floor surface F is maintained even when the pivot shafts 14, 14 are in either the lifting state or the non-lifting state. The wheels 12, 12 are always kept in a constant vertical position without any fluctuation in
It is possible to always obtain a good direction control effect without impairing the turning performance of the vehicle.

However, in conventional manually operated pallet trucks, the rear steering wheels change their angle with the floor together with the jack when the jack is used for lifting, so the wheels could not be configured as casters, and at best they were provided as an integrated double wheel set that swiveled together with the jack at one central location for steering, which meant that they essentially had to be a three-point ground contact type and were inevitably lacking in stability, but this problem has been solved as described above, and the rear steering wheels 12, 12 can be configured as casters and can be provided at two locations, one on the left and one on the right, spaced apart, making it possible to have a four-point ground contact type. This pallet truck is therefore very stable, with minimal risk of tipping over even when the load is high, and the load carrying capacity can be significantly increased compared to conventional trucks. As a result, it is now possible to use the truck in a way that allows it to be guided by a guide car and used to transport cargo, something that was impossible with conventional pallet trucks.

As is clear from the description of the above embodiments, according to the present invention, in particular, the receiving member portion provided at a predetermined portion of the cargo receiving truck section can be slid onto the lift operating member of the lift jack of the lifting truck section. Place it freely,
By connecting the receiving truck and the lifting truck with at least two upper and lower parallel link levers of equal length, the steering wheels of the lifting truck can be kept in contact with the floor when the lift is operated by jacks. This makes it possible to configure the wheels as casters and install them at two locations on the left and right at intervals, thereby making it possible to create a four-point grounding system. This is a manually operated pallet truck that is very stable and has a high load carrying capacity compared to the conventional one, and various similar lift types. Since the child is arranged so as to be able to slide freely in the front and rear direction, the load-receiving trolley part A
It is possible to effectively absorb the misalignment between the receiving member portion and the lift operating member that occurs when the lift member moves up and down, thereby further improving stability.

[Brief explanation of the drawing]

The drawings show an example of a pallet truck that is an embodiment of the present invention, in which Fig. 1 is a perspective view, Fig. 2 is a partially cutaway front view seen from the rear side, and Fig. 3 is a partially cutaway front view.
The figure is a side sectional view, Figure 4 is a side sectional view in a lifted state,
FIG. 5 is a perspective view of the upper link lever, and FIG. 6 is a perspective view of the lower link lever. A... Cargo receiving truck section, B... Lifting truck section,
DESCRIPTION OF SYMBOLS 1...Frame part, 2...Fork part, 3...Wheel, 6...Receiving member part, 9...Lever for vertically operating the wheel, 10...Base, 11...Jet holding frame, 12...Wheel , 13...lift jack,
17... Lift operating member, 18... Roller, 20
...Upper link lever, 21...Lower link lever, 26...Lever, 27...Connection rod.

Claims (1)

[Scope of utility model registration request] The cargo-receiving trolley section has wheels that can be moved up and down by a vertical operating lever, and a lift truck section has lift jacks and wheels, and the cargo-receiving trolley section has a load-receiving trolley section at a predetermined part of the cargo-receiving trolley section. The provided receiving member portion is slidably placed on the lift operating member of the lift jack disposed at the rear end of the lift truck portion, and the receiving member portion and the lift operating member are A plurality of rolling elements are disposed to be slidable in the front-rear direction, and at least one of the upper and lower at least two parallel link levers of equal length is connected to the cargo receiving truck section and the lifting truck section. A lift-type cargo transport vehicle characterized in that a lever for vertically operating the wheels of the cargo receiving truck portion is interlocked and connected to the lever.