EP0853061B1 - Universal drive for a gripper - Google Patents

Abstract

The central drive (1) mechanism in the grab`s vertical axis has a drive shaft (2) which is turned coaxially with the central axle. The translational and rotary movements of the drive shaft are controlled separately. A bushing (3) is detachably and positively connected to the drive shaft so that the movements of the drive shaft are transferred to the bushing. The exterior of the bushing has toothed racks. The bushing, as connection with a toothed sector (6), transfers the vertical movements from the central drive to the toothed sectors which, in turn, perform a swivel motion which is transferred to the grappling arms (12) fixed to the toothed sector.

Description

The invention relates to a gripper for bulk or general cargo with a universal drive for common vertical movement and force control of the gripper arms as well as the rotating one Movement of the gripper arms around the vertical axis of the gripper.

In all previously known grippers, separate drive units are required in each case for the opening and closing of the gripper arms or for the rotation of the gripper. Here, electromechanical or electrohydraulic drive systems are known, the electromechanical motor grippers being designed primarily as clamshell grabs and the shell movement being carried out via a spindle drive, while the electro-hydraulic polyp grippers open and close the shells or tines via hydraulic linear motors.
It is characteristic here that the movement of the polyparms is carried out by a separate drive. The polyparms are articulated on the polyparm carrier and are moved by means of the hydraulic pressure energy via the linear motors, which are pivotably mounted on the one hand on the polyparm carrier and on the other hand on the polyparm itself. The rotary movement of the gripper is carried out by rotary motors limited in angle of rotation or endless hydraulic motors, which enable the rotation of the gripper either directly or via an intermediate gear.
Grippers that are equipped with hydraulic hoses to supply the linear motors only guarantee a limited rotational movement.
In order to eliminate these disadvantages, grippers have been developed according to document DE 24 28 566 A1, which are provided with a distributor head arranged in the axis of rotation.

The endless rotation is given here, but here too hydraulic lines are required which lead to the linear motors actuating the polyparms.
None of the grippers listed can be converted to another type of gripper without changing the drive technology. The structural design determines the area of application. It can be assumed that the drive technology of the clamshell grab is fundamentally different from that of a polyp grab.
The known motor clamshell buckets are not excluded from this.
Grippers are listed in which the shells are suspended from the upper of the two cross members, whereby it is disadvantageous that the rods present between the cross members are relieved and the lifting cylinders are loaded by the gripper weight and bulk material. This design results in a reduction in the closing forces on the shell cutting edges.
This disadvantage is avoided by the solution described in DE 31 51 519 A1, according to which the gripper is suspended from the lower crossmember in order to increase the gripper closing force in this way.
According to document DE 41 22 713 A1, clamshell grabs are designed, on the legs of which the shells are mounted about their mutually parallel pivot axes, which are functionally operated by a transverse hydraulic linear motor via articulated actuating levers.

GB 597630 describes a load gripping device low height with integrated motor for in particular Bulk goods, their mechanically controlled operation done via racks and gears. The hydraulic powered motor forms with those in the same Level deflection points of the pincer-like gripper arms a compact unit and is encapsulated.

The limitation of this solution is particularly disadvantageous on a pair of gripper arms, as well as the missing integrated Rotary control.

US 3627372 describes a hydraulically controlled gripper with an integrated vertical central motor and a rotary motor, the polyparms of which have a common, torque-free axial force control with rotating axial force coupling and can be rotated with a rotary motor about an axis of rotation.
A particular disadvantage is the high constructional height and the lack of the possibility of converting the polyarms in terms of number and degree of opening without changing the drive technology.

The disadvantage is the complex for all listed gripper types Supply technology, the risk of destroying the Hydraulic lines involved in the pivoting and the separate drive technology for the Polyparmbzw. Shovel movement. Grabs of this type are relatively high built because the linear motors operate the polyparms are inclined. The overall height is additional enlarged because the rotary motor above the polyparm carrier is arranged so that the vertical action area of such a hoist is restricted or highly projecting carrier objects required.

The object of the invention is a universal drive for a gripper to develop that on grippers required pivoting movement of the gripper arms in the form of Blades or polyparms as well as the rotation about the vertical axis, independently of each other, by a centrally stored Drive enables to the otherwise usual, separate Drive units in the form of hydraulic linear and Rotary motors for each of the types of movement by one drive low height, in which the drive and the joints of the Gripping arms are protected to replace.

According to the invention the object is achieved in the claim 1 specified features solved. The beneficial Further developments of the invention result from the subclaims.

The present central drive of the gripper, with the separately controllable movement of the Drive shaft for the purpose of rotation or polyparm actuation on the gripper, characterizes the essentially new of the inventive Solution with the advantages of Convertibility, reduction in height and shielded Joint technology.

• dass mittels eines Antriebes alle erforderlichen Bewegungsabläufe des Greifers vollzogen werden,
• dass die Greiferarme austauschbar sind, ohne die Antriebstechnik zu wechseln,
• dass der Greifer mit 1 bis 12 Polyparmen bestückt werden kann und
• dass alle Gelenkpunkte im dreigeteilten Schutzgehäuse angeordnet sind, womit sperriges, toxisches und korrosionsförderndes Greifgut erfaßt werden kann, ohne daß der Antrieb mit diesem in Verbindung tritt.

The advantages of the invention are

• that all necessary movements of the gripper are carried out by means of a drive,
• that the gripper arms can be replaced without changing the drive technology,
• that the gripper can be equipped with 1 to 12 poly arms and
• that all articulation points are arranged in the three-part protective housing, with which bulky, toxic and corrosion-promoting goods can be gripped without the drive coming into contact with them.

• mit Figur 1 als Vorderansicht des mit Zinken ausgerüsteten Polypgreifers,
• mit Figur 2 als Draufsicht des mit Zinken ausgerüsteten Polygreifers,
• mit Figur3 als Halbschnittdarstellung des Polypgreifers,
• mit Figur 4 als Halbschnittdarstellung des Polyparmantriebes,
• mit Figur 5 als Draufsicht der Lagerung des Zahnsektors, als ein Ausführungsbeispiel eines Polypgreifers ohne Zusatzzylinder, und
• mit Figur 6 als ein Ausführungsbeispiel eines Polypgreifers mit Zusatzzylinder.

The invention is as follows

• 1 shows a front view of the polyp gripper equipped with prongs,
• 2 shows a top view of the poly gripper equipped with tines,
• with Figure 3 as a half-sectional view of the polyp gripper,
• 4 as a half-sectional view of the polyparm drive,
• with Figure 5 as a top view of the bearing of the tooth sector, as an embodiment of a polyp gripper without additional cylinder, and
• with Figure 6 as an embodiment of a polyp gripper with additional cylinder.

According to the embodiment of the polyp gripper without an additional cylinder, a central unit 1 lying in the vertical axis of the gripper has a drive shaft 2 which can be displaced in the vertical axis and rotated about the same. This drive shaft 2 carries a positively coupled pot bushing 3, which is slidably mounted on the upper outer casing 4 of the central drive 1. The form-fitting coupling takes place via the square 5 of the drive shaft 2. In this way, the pot sleeve 3 executes all movements which are transmitted from the central drive 1 to the drive shaft 2. The pot sleeve 3 is formed on the upper outer casing 4 over the width of a toothed sector 6 as a rack body 7 and is able to move due to the tooth engagement of the pivotably mounted toothed sector 6. The tooth sector 6 is supported in a bearing 8 via a bolt 9 which is fastened by screws 10 in a bearing plate 11.
The tooth sector 6 is the carrier of a polyparm 12 which is detachably coupled to the same via screws 13. The central drive 1 is surrounded by a three-part housing, which disintegrates into individual parts: protective cap 14, polyparm carrier 15 and rotor bearing 16. The number n of polyparms 12 is identical to the number of tooth sectors 6. It lies in the border areas 1 <n <12. The central drive 1 is mounted in the rotor bearing 16 via a flange 17 in an axial bearing 18. The rotor bearing 16 is connected to the polyparm carrier 15 by screws 19 and in this way transmits the loads to the axial bearing 18. The protective cap 14 is connected to the polyparm carrier 15 by screws 20 and thus encapsulates the joints of the drive system with respect to the material to be gripped.
In this exemplary embodiment, the gripper is provided with six poly arms 12 which are connected to the poly arm sector 21 by screws 13. The central drive 1 consists of a rotor 22 and a linear motor 23, which are supplied with the pressure medium via supply lines 24 and 25 or execution lines 26 and 27. The connections of the supply lines are made on the fixed outer housing of the rotor 22.
The pressure medium is added or removed via an end flange surface 28. dissipated to supply the linear motor 23. The pressure medium is passed through bores 29 into the respective piston chambers of the linear motor 23. The gripper is connected to a rotor housing 30 via the bore 31 to the respective carrier device.

According to FIG. 6, the extension through an additional cylinder 32 installed in the protective cap 14 and its function and interaction with the linear motor 23 is shown by the half section through the central drive of the gripper with additional cylinder.
Inside the protective cap 14, a form-fitting outer cylinder jacket 33 is fitted, which is fastened to a floor 35 with screws 34.
The pot sleeve 3 is formed in the lower region as a piston 36 and receives grooving for receiving guides 37 and a piston seal 38. The pressure medium supply to the additional cylinder 32 takes place via a bore 39 which is connected to the feed bores which connect the pistons of the linear motor 23 move and in this way ensure the rectified movement of the piston 36 of the additional cylinder 32.

The pressure medium emerging from the bore 39 is in a Chamber space 40 directed to the outside atmosphere is sealed by an inner piston 41. About one Outer jacket 42 of the linear motor 23 thus slide guides 43 and an associated piston seal 44. Das Pressure medium comes out of the chamber space 40 through a bore 45 in a pressure chamber 46 and thus ensures, in the event of exposure with pressure medium, for an additional force that via the rack body 7 and toothed sector 6 on the gripper takes effect. The pressure chamber 46 is emptied when the Drive shaft 2 of the linear motor 23 moved vertically downwards will and in this way, due to the influence of the Piston 36, the pressure medium located in the pressure chamber 46 through the holes 45 and 39 in the process-oriented Channel of the linear motor 23 presses.

The function of the universal drive for grippers is characterized by
that a central drive 1 arranged in the vertical axis of the gripper is provided, which has a drive shaft 2 which is displaceable and rotatable coaxially to the central axis.
The translational and rotational movement of the same can be controlled independently of one another. A pot sleeve 3 is positively but releasably coupled to this drive shaft 2, so that the movements of the drive shaft 2 are transmitted to the pot sleeve 3 in this way.
The outer contour of the pot sleeve 3 carries racks, the number of which corresponds to the number of polyparms 12 to be moved by the gripper. The toothed racks can be part of the pot sleeve 3 or are detachably connected to the pot sleeve 3 in the form of rack elements. The pot sleeve 3 as a coupling member to the tooth sector 6 transmits the vertical movement applied by the central drive 1 to the tooth sectors 6, which in turn, as a result of the mounting of a pivot, are carried out and are transmitted to the polyparms 12 fastened to the tooth sector 6. The form-fitting coupling of the elements of this drive chain also ensures that the gripper can rotate. The rotation and displacement of the drive shaft 2 is the crucial prerequisite for the design of the gripper according to the invention.

The central drive arranged in the central axis of the gripper 1 concentrates all the joints required for movement around this central axis, making it possible to use the same good protection against external influences. This requirement enables easy removal of the polyparms 12 and thus the convertibility of the gripper. So it is easy possible to increase or reduce the number of gripper arms or to exchange it for other Polyparm grippers. The crucial requirement to this kind of practical Allowing use is the design of the pot tins 3, whose division number determines the possible range of variation, z. B. is a number of polyparms between 1 and 12 possible. The central drive 1 rests on a three-part Polyparm carrier 14; 15; 16. The middle polyparm carrier 15 is the number of maximum polyparms available 12 divided into sectors and becomes solvable with the monolytic upper and lower supports as rotor bearings 16 connected as a protective cap 14. Each polyparm 12 is over Screws 13 coupled to the tooth sector 6, which in the end shields 11 of the middle polyparm carrier 15 is pivotable is stored. The upper polyparm carrier as rotor bearing 16 is designed as a thrust bearing. The flange is stored in it 17 of the central drive 1, which transmits the central loads and at the same time also enables the rotation of the gripper. The lower polyparm carrier encapsulates as a protective cap 14 the central drive 1 relative to the material to be gripped, so that the Central drive 1 protected against external influences is. In the lower Polyparmträger as a protective cap 14 can An additional cylinder increases the closing forces of the gripper 32 are provided, the fluid supply with the linear motor 23 of the central drive 1 in connection stands and is carried along in the rhythm of the movement. The exchange the middle polyparm carrier 15 in connection with the pot sleeve 3, which acts as an adapter between the tooth sector 6 and drive shaft 2 of the central drive 1 functions, allows the design diversity of the gripper.

A particularly advantageous variant is the use of the central drive 1 for a clamshell bucket that is operated without tooth sectors 6. For this purpose, the cup wheel 3 is provided with claw arms which engage directly in the link-like guides of the bowl side walls and thus open or close the bowls of the gripper. The shells are advantageously mounted in a common swivel axis, which enables a space-saving design. The central drive 1 is supplied with pressure medium via supply lines 24; 25, which are securely connected to the fixed part of the housing.
The pressure medium reaches the corresponding chambers of the consumers via bores (rotor 22 and linear motor 23 of the central drive 1). Two pressure flows which can be controlled independently of one another are supplied in order to control the two main movements of the central drive 1 in this way.

Reference symbols used

1

Central drive

2

drive shaft

3

gland

4

upper outer jacket

5

square

6

toothed sector

7

Rack body

8th

camp

9

bolt

10

screw

11

end shield

12

Polyparm

13

screw

14

protective cap

15

Polyparmträger

16

rotor bearing

17

flange

18

thrust

19

screw

20

screw

21

Polyparmsektor

22

rotor

23

linear motor

24

feed pipe

25

feed pipe

26

discharge line

27

discharge line

28

Stirnflanschfläche

29

drilling

30

rotor housing

31

drilling

32

additional cylinder

33

Cylinder outer jacket

34

screw

35

ground

36

piston

37

guide

38

piston seal

39

drilling

40

chamber space

41

internal piston

42

outer sheath

43

guide

44

piston seal

45

drilling

46

pressure chamber

Claims (4)

1. Gripping device for bulk or piece material having a universal drive for the common vertical movement and power-control of the gripping device arms and the rotational movement of the gripping device arms about the vertical axis of the gripping device having an integrated hydraulic central drive (1) which is formed as a compact unit, has a low installation height and is protected from external influences, characterised in that the central drive (1) lying in the vertical axis of the gripping device comprises a drive shaft (2) which is displaced coaxially with respect to the vertical central axis and is rotated about same, wherein the vertical and rotating movements of the drive shaft (2), which can be controlled independently, are transmitted to a cup bushing (3), to the outer sleeve of which are attached toothed rack bodies (7) which at each grapple arm (12) are in engagement with a toothed sector (6) which is fixedly connected to the grapple arm and which, as a result of the bearing arrangement of the toothed sector (6) in a bearing (8) by means of a pin (9), is able to perform a pivot movement within the limits of the deflection points which are determined by the extent of the vertical movement of the central drive (1) and in the closed and fully open state lie in the boundary layers of the toothing arrangement of the toothed rack body (7).
2. Gripping device according to claim 1, characterised in that the number n of grapple arms (12) is identical to the number n of toothed sectors (6) disposed on the periphery of the cup bushing (3).
3. Gripping device according to claim 2, characterised in that the grapple arms (12) can be displaced vertically in relation to the cup bushing (3).
4. Gripping device according to claim 1, characterised in that inside a protective cap (14) there is disposed a cylinder outer sleeve (33) which together with the cup bushing (3) in the form of a piston (36) forms an additional cylinder (32).

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