CN107226433B

CN107226433B - Ground transport means with traction rod

Info

Publication number: CN107226433B
Application number: CN201610171047.3A
Authority: CN
Inventors: 丹尼尔·明奇; 潘先耀; 蔡宿翎
Original assignee: Jungheinrich AG
Current assignee: Jungheinrich AG
Priority date: 2016-03-23
Filing date: 2016-03-23
Publication date: 2020-10-16
Anticipated expiration: 2036-03-23
Also published as: CN107226433A

Abstract

An industrial truck having a drawbar with a drawbar head, a longitudinally extending drawbar tube and a drawbar coupling, wherein the drawbar tube is mounted in the drawbar coupling so as to be pivotable about a horizontal axis and is provided with a spring element which is arranged in a manner projecting from the drawbar tube and is arranged on the drawbar coupling in order to pretension the drawbar tube into its defined region, wherein the spring element has a gas spring which accommodates the end of the gas spring and has a bearing surface on the side pointing forward from the gas spring for a pin arranged transversely to the longitudinal direction of the drawbar tube, wherein the pin has a curved bearing surface such that the gas spring guide assumes a defined position on the pin in the spring-pretensioned condition.

Description

Ground transport means with traction rod

Technical Field

The invention relates to an industrial truck having a drawbar with a longitudinally extending drawbar tube having a spring element which adjusts the drawbar into a predetermined position.

Background

In ground vehicles with a tow bar, it is known to: the spring element is arranged in the interior of the drawbar tube. The spring element interacts at one end with the drawbar arm and is coupled to the opposite end in a fixed manner on the vehicle, so that the drawbar arm is prestressed by means of a spring pretension, for example into an approximately vertical position.

In the installation of the spring element, it is particularly difficult to fix the spring element in the drawbar tube, since the drawbar is designed as a closed tube in which the installation takes place from the outside, without visibility, and with a restricted access. This work step is often not easily performed and costly by personnel who are just unfamiliar with the installation.

Disclosure of Invention

The object on which the invention is based is: an industrial truck with a tow bar is provided, which allows a simple installation of the spring element in the tow bar arm.

According to the invention, the ground transport means is equipped with a drawbar having a drawbar head, a longitudinally extending drawbar tube and a drawbar coupling. The drawbar coupling is fixed to the vehicle and can be connected, for example, to a pivot bearing provided on the vehicle. The drawbar tube is mounted in the drawbar coupling in a pivotable manner about a horizontal axis. In this way, the drawbar can be pivoted and its height and its angle of inclination are adapted to the desired position. Furthermore, a spring element is provided, which protrudes from the drawbar tube in such a way that it is arranged therein. The end projecting from the drawbar tube is arranged on the drawbar coupling and preferably vertically pretensions the drawbar tube into a defined region. The spring element for prestressing has a gas spring and a gas spring guide which receives the end of the gas spring and has a bearing surface for a pin arranged transversely to the longitudinal direction of the drawbar tube on the side pointing forward from the gas spring. The pin likewise carries a bearing surface with a curved shape, which causes the gas spring guide to assume a defined position on the pin under spring pretensioning. In contrast to the prior art, in which the gas spring guide has a button hole, in the solution according to the invention the bearing surface and the pin and the gas spring guide come into abutment with one another, wherein the retaining pin is guided through the button hole. The contour is selected such that the gas spring guide and the pin occupy a defined position relative to one another. This is particularly simplified in terms of installation, if the pin no longer has to be guided through a button hole in the gas spring guide, but only has to be brought into abutment.

In a preferred embodiment, the gas spring guide has a cylindrical receiving section which receives an end of the gas spring. The gas spring guide is fitted with its receiving section onto the gas spring. Preferably, the receiving section has a rounded base in which the gas spring is centered. In this way a defined position is formed between the gas spring guide and the gas spring. The gas spring guide is fitted over the gas spring. The process of fitting takes place without further fixing measures and can be carried out extremely simply as an installation step. In order to fix the pin forming the seat for the gas spring guide, the drawbar tube has two bores lying opposite one another, in which the pin is fitted. The position of the bore is coordinated in this case such that the gas spring, which has completed the installation, exerts sufficient pressure on the gas spring guide in any position of the drawbar in order to hold said gas spring guide against the pin. In the vertical drawbar position and also in the horizontal drawbar position there is always a spring force so much that the gas spring guide remains against the pin.

In a preferred embodiment, the pin has a rotationally symmetrical contour, the diameter of which decreases in the longitudinal direction of the pin towards its center. The pin therefore has a profile for this which is rotated, the diameter of the profile increasing or remaining constant starting from the center of the pin towards the ends. This results in: the gas spring guide with its bearing surface continuously migrates into the center of the pin, since at least the spring is compressed here. The geometric shapes of the spring and the pin cooperate with one another to guide the bearing surface of the pin into a defined position without the gas spring guide being fixed in the corresponding position on the pin.

In a preferred embodiment, the bearing surface is laterally delimited by two projecting webs. The spacing between the webs allows the accommodation of pins which in this way come into contact with the bearing surface. The lateral webs form the shape of the lateral securing element and prevent: the gas spring guide is disengaged from the pin during vibration, impact, etc.

Furthermore, in order to align the gas spring guide on the pin, the bearing surface has a curved shape, wherein the bearing surface protrudes centrally. The projecting bearing surface cooperates with the pin and its radius which decreases toward the center in such a way that the gas spring guide is centered on the pin. The bearing surface preferably protrudes spherically and has a rounded shape.

Drawings

A preferred embodiment of the present invention is described in detail below.

It shows

Figure 1 shows a side view of a low-ride flat car,

figure 2a shows a partial view of a drawbar arm,

figure 2b shows a drawbar arm according to the prior art,

figure 3 shows a tow bar according to the invention,

FIG. 4 shows a pin according to the invention, and

fig. 5 shows a cross-sectional view of a gas spring guide according to the invention.

Description of the symbols

10 vehicle

12 drive component

14 wheels

16 draw bar

18 draw bar head

20 draw rod tube

22 drawbar connection

22a drawbar connection part (drawbar side)

22b draw bar connector (vehicle side)

24 load member

25a, b cable

26 load fork

28 bolt

30 nut

32 head section

34 through hole

36 gas spring guide

38 plug connector

40 pin

41 safety element

42 pin head

44 connecting section

46 central region

48 gas spring guide

50 bearing surface

52 connecting sheet

54 accommodating part

56 substrate

58 gas spring

60 ends of gas springs.

Detailed Description

Fig. 1 shows a side view of a tow bar guided low-ride flat car 10. The truck 10 has a drive member 12 with steered and driven wheels 14. The drive member 12 has a drawbar 16 having a drawbar head 18, a drawbar tube 20, and a drawbar coupling 22. The drawbar 16 is pivotable about an axis extending horizontally in the drawbar coupling 22. The dashed line position of the drawbar 16 corresponds to an approximately horizontal position and produces a lift of the load member 24. The load part 24 has two load forks 26, which are shown in fig. 1 in a lowered position for receiving a load. The raised position of the load forks 26 is shown in phantom. Via the traction rod 16, not only is the lifting of the load fork 26 controlled, but also the driven wheel 14 is steered. In this regard, the tow bar 16 is pivotable about a vertical axis V. A vertical axis V as shown in fig. 1 can extend through the midpoint of the driven wheel 14.

Fig. 2a shows a detailed structure of a drawbar tube in the prior art. The drawbar tube 20 is made of a right-angled profile which is stamped on the drawbar head 18 on one end and on the drawbar coupling 22 on the other end. The drawbar coupling 22 has a part 22a arranged on the drawbar tube 20 and a part 22b fixed to the vehicle. The two parts are pivotable relative to each other about a horizontal axis, wherein the part 22b fixed to the vehicle is mounted pivotably about a vertical axis. In the drawbar tube 20, cables 25a, b are provided, via which, for example, electrical control signals can be exchanged between the drawbar head and the vehicle. The drawbar tubes 20 each have a bore 26 on opposite sides, which receive a pin-shaped pin 28. The bolt 28 inserted through the drawbar tube 20 is secured on the opposite side via a nut 30. The pin 28 is guided through the head section 32 and is secured on the opposite side. The head section 32 has a central through-opening 34 through which the pin 28 is guided.

When the drawbar arm is mounted, the gas spring guide 36 is introduced into the drawbar tube 20 from one end and is secured there by the pin 28. For this purpose, the pin 28 must be guided through the hole 34 of the correctly positioned head section 32.

Fig. 3 shows a drawbar tube 20 according to the invention with its drawbar coupling 22 a. Furthermore, the electrical cable 25 with the plug connection 38 associated with it is guided out of the drawbar tube 20.

The drawbar tube 20 has a lateral bore 26 in which a pin 40 is secured. The pin 40 is secured via a securing mechanism 41. Fig. 4 shows the structure of the pin 40 in detail. The pin 40 has a pin head 42 with a diameter greater than the diameter of the bore 26. The opposite end of the pin 40 has a connecting portion 44, on which the securing element 41 can be placed, wherein the diameter of the securing element 41 is also larger than the bore 26.

The region of the pin 40 between the head section 42 and the connecting section 44 is formed rotationally opposite, and the smallest diameter is arranged centrally with respect to the pin longitudinal direction. The diameter D begins at the central region 46 and increases toward the end of the pin.

The pin 40 cooperates with a gas spring guide 48. The gas spring guide 48 has a bearing surface 50 on its side pointing toward the pin, which is laterally delimited by a web 52. The webs 52 are arranged parallel to one another at a distance and together with the base 50 form a kind of receiving groove for the pin 40. As is also shown in the sectional view in fig. 5, the gas spring guide 48 has a cylindrical receptacle 54, the base 56 of which is arched. The gas spring guide 48 is fitted with the receptacle 54 onto the end 60 of the gas spring 58. The end 60 is formed with a button hole, which however has no function, since the gas spring guide 48 is only loosely fitted. The gas spring is centrally positioned in the gas spring guide by means of a camber in the base of the gas spring guide. The gas spring guide 48 is held by the spring force of the spring 58, which is always sufficient to maintain the abutment between the pin and the gas spring guide in the horizontal and vertical position of the drawbar.

The installation of the tow bar requires only the insertion of the pin 40 into the tow bar pipe and the securing thereof in the inserted state. The gas spring guide 48 can then be used, where care must only be taken to orient the connecting piece 52 laterally to the pin and the pin 40 to come into contact with the base 50 of the gas spring guide. The reduced diameter d in the center of the pin 40 and the curvature of the bearing surface 50 ensure that: the gas spring guide 48 is positioned centrally in the pin 40 and thus occupies a defined position without damaging the cable 25 which is also guided through the drawbar tube.

Claims

1. An industrial truck having a drawbar (16) with a drawbar head (18), a longitudinally extending drawbar tube (20) and a drawbar coupling (22), wherein the drawbar tube (20) is mounted pivotably about a horizontal axis in the drawbar coupling (22) and is provided with a spring element (58) which is arranged in a manner projecting from the drawbar tube (20) and on the drawbar coupling (22) in order to pretension the drawbar tube (20) into its defined region, characterized in that the spring element (58) has a gas spring and a gas spring guide (48) which accommodates an end (60) of the gas spring and has a bearing surface (50) on the side pointing forward from the gas spring for a pin (40) arranged transversely to the longitudinal direction of the drawbar tube, wherein the pin (40) has a curved bearing surface, so that the gas spring guide (48) assumes a defined position on the pin under spring pretensioning.

2. An industrial truck according to claim 1, characterized in that the gas spring guide (48) has a cylindrical receiving section (54) which receives an end (60) of the gas spring.

3. An earth vehicle according to claim 2, characterized in that the receiving section (54) has a rounded base (56) in which the gas spring is centered.

4. An industrial truck according to any one of claims 1 to 3, characterized in that the drawbar tube (20) has two bores (26) opposite each other, in which bores the pins (40) are mounted.

5. An earth vehicle according to any one of claims 1-3, characterized in that the pin (40) has a rotationally symmetrical profile, the diameter (D) of which decreases in the longitudinal direction towards the centre of the pin.

6. An industrial truck according to any one of claims 1 to 3, characterized in that the bearing surface (50) is laterally delimited by two projecting lugs (52) whose spacing allows the pin (40) to be accommodated between the lugs (52).

7. An earth vehicle according to any one of claim 6, characterised in that the bearing surface (50) projects centrally between the connecting pieces (52).