GB2335872A

GB2335872A - Grinding machine.

Info

Publication number: GB2335872A
Application number: GB9806573A
Authority: GB
Inventors: Philip Anthony Mansfield
Original assignee: Individual
Current assignee: Individual
Priority date: 1998-03-28
Filing date: 1998-03-28
Publication date: 1999-10-06
Also published as: GB9806573D0

Abstract

The machine has a frame 10 with adjustable feet 24 on which it stands on a surface 31 in which a shallow rectangular recess is to be ground. A movable carriage on which an electric motor 46 driving a grinding drum 48 is pivotally mounted on an arm 43 and has a handle 50 for manually gripping is slidable in the frame 10 on linear bearings 40, 42. Pushing the carriage forwards allows the grinding drum 48 to form the recess in the surface 31. A depth of the recess is controlled by adjusting the height of the drum 48. This is done by a screw 56 which adjusts the position of a jockey wheel running on a side-member 12b of the frame 10. The grinding drum has diamond grinding elements which are arranged on the curved surface of the drum on helical path (see figure 4). The recess formed is particularly suitable for receiving a floor-identification plate in a warehouse.

Description

2335872 1 GRINDING MACHINE.

This invention relates to grinding machines.

The invention is particularly concerned with the grinding of a relatively shallow recess in a surface, usually a substantially horizontal surface. The recess is usually of a substantially rectangular shape in plan.

one situation in which the need to provide such recesses arises is in the labelling of floors in buildings such as warehouses. It is often necessary to provide in such situations a floor label which is readable by man and/or machine and which is located in the surface of a floor of the warehouse. The label typically identifies the articles which are located nearby and, to be machine-readable, often includes a barcode, together with other information.

Because machines such as fork-lift trucks, including those which read the labels, often pass over the labels whilst carrying out their operations, it is highly desirable that the labels be recessed in the floor surface to prevent damage to them but have their upper surfaces accurately located to facilitate machine reading of the labels.

The object of the present invention is to provide a machine which is capable in a simple manner of producing a recess suitable for receiving an identification label of kind referred to above.

According to the present invention, there is provided a machine for grinding a recess in a surface, comprising frame means for being positioned in a static location relative to the surface, a rotating grinding means mounted on the frame means, drive means for causing the grinding means to rotate about an axis of rotation thereof, whereby the grinding 1 2 surface of the grinding means makes grinding contact with the surface, and means for allowing movement of the grinding means relative to the frame means in at least one direction so that the grinding contact with the surface forms in the surface a recess extending in the said direction. - Preferably, the grinding means is also movable relative to the frame means in directions to vary the depth of penetration of the grinding means into the surface and thus the depth of the recess formed.

Conveniently, the grinding means is pivotally movable relative to the frame means.

Preferably, the machine has resilient biasing means for biasing the grinding means away from the surface to be ground.

is Advantageously, the grinding means is movable relative to the frame means in the second direction between a first position, in which the grinding means is clear from the surface in which the recess is to be formed, and a second position, in which the grinding means makes grinding contact with the surface.

Preferably, there is a means for adjustment of the second position, conveniently comprising a rolling element the position of which relative to the grinding means can be adjusted and which makes rolling contact with the frame means during movement of the grinding means relative thereto in the direction of extent of the recess.

The means-for allowing movement of the grinding means relative to the frame means conveniently allows rectilinear relative movement. This facilitates formation of a rectangular recess.

Advantageously, the grinding means, and conveniently also 3 its drive means, is mounted on a carriage which is movable rectilinearly relative to the frame means, the carriage being conveniently mounted in linear bearings to allow its movement relative to the frame means. 5 The extent of movement of the grinding means relative to the frame means is advantageously adjustable, for example by suitable adjustable stop means. The drive means is conveniently an electric motor. The apparatus advantageously includes means for adjustment of the position of the frame means relative to the surface to be ground. These adjustment means conveniently comprise a plurality of feet for contacting the surface, the feet being adjustable manually relative to the frame means.

Conveniently, to facilitate its movement from one place of operation to another, the frame has at one end rotatable elements, for examples wheels, which do not contact the surface to be ground when the machine is positioned for operation but which can be brought into contact with the surface by tipping the machine into a position for movement to another place of operation. Advantageously, the frame means at the end opposite to the rotatable element has a portion for convenient manual gripping during such movement.

Preferably, the grinding means comprises a rotatable cylinder having means allowing its mounting for rotation relative to its cylindrical axis and having cutting elements on its cylindrical surface.

The inven tion also provides, for use in a grinding machine as referred to above, a grinding means comprising a rotatable cylinder having means allowing its mounting for rotation relative to its cylindrical axis and having cutting elements on its cylindrical surface.

4 The cuttingelements advantageously comprise diamond.

The cutting elements are preferably arranged along a helical path around the cylindrical surface.

Preferably, each cutting element is rectangular in cross- section in the radial plane of the cylinder and, more preferably, elongate in the circumferential direction of the cylinder.

Advantageously, each cutting element abuts its neighbouring elements in the circumferential direction but is offset relative thereto in the axial direction. The offset is preferably less than the axial extent of each element.

An embodiment of the invention will now be described by way of example with reference to the drawings, in which:

Figure 1 is a side view of a grinding machine, is Figure 2 is a plan view of the machine shown in figure 11 Figure 3 is an end view, as seen in the direction of the arrows III-III on figure 2, of the machine shown in figure 1, Figure 4 is a side view of a grinding drum of the apparatus of figure 1, and Figure 5 is an end view of the grinding drum of figure 4.

The machine shown in f igures 1 to 3 has a main frame which is rectangular in plan and is formed from parallel longitudinal side members 12, a rear end member 16 and a front end plate 18. The side members 12 and the rear end member 16 are formed from square- section tubular steel. Each side member 12 has first, second, third and fourth portions 12a 12b, 12c and 12d arranged so that the frame has vertical front 30 portion formed by the first side member portions 12a and a stepped down rear portion formed by the third and fourth side member portions 12c, 12d and the rear end member 16. The front end plate 18 extends between the side member portions 12a, the lower edge of the front end plate lying at approximately the same distance from the side member second portions 12b as the rear end member 16 of the frame. A strengthening plate 20 is fitted at each side of the frame between the first and second side member portions 12a, 12b.

The frame 10 has four feet 24 which are fitted two at each side of the frame to the fourth side member portions 12d and to the lower end of each first side member portion 12a. The feet 24 are adjustable relative to the frame 10 by screwthreaded engagement of stems 25, to which the feet are attached, into corresponding screw- threaded sockets 26 on the frame.

is Two wheels 27 are fitted to the end plate 18, each wheel being journalled on a respective axle 28 between a pair of mounting plates 30 which are attached to the front end plate 18. The wheels 27 are positioned so as not to make contact with a floor surface 31 when the machine is standing on the surface 31 on its feet 24.

Fitted internally of each side member 12 adjacent the front end of the second portion 12b is a guide rod 32 which is mounted at its respective ends on forward and rearward mountings 36, 38 secured to the inner surface of the side member second portions 12b. Each guide rod 32 passes through respective forward and a rear-ward linear bearings 40, 42. The four linear bearings 40, 42 are secured at respective corners of a horizontal plate 44 which thus forms part of a movable carriage which is slidable on the guide rods 32.

To the lower side of the plate 44 is mounted an electric motor 46 which drives a grinding drum 48 mounted for rotation 1 6 on the output shaft of the motor 46. The electric motor 46 is attached to a strut 43 which pivots around a pivot point 45. The pivot point 45 is fastened to a vertical rectangular plate 51 which is secured along its upper edge to the horizontal plate 44 of the carriage. Located inside the vertical plate 51 is a helical compression spring 47 which acts between a seating 53 on the strut 43 and a seating (not shown) on the vertical plate 51. The helical compression spring 47 provides a lifting force on the electric motor 46 and the grinding drum 48 and thus biases the electric motor 46 and grinding drum 48 into an upward position. The drum 48 is covered, except at its lowest part, by a guard 49. To allow for manual sliding movem ent of the carriage on the guide rods 32, the carriage is fitted with a hand grip 50 which extends rearwardly from the plate 44, to which it is secured, and allows the carriage, including the motor 46 and grinding wheel 48 to be moved back and forth along the guide rods 32. The drum 48 is shown in figures 4 and 5 and described below in more detail with reference thereto. 20 The limit of forward travel of the carriage on the guide rods 32, 34 is determined by an adjustable end stop 52 which passes in screw-threaded engagement through a hole in the front end plate 18 of the frame 10 and is positioned to abut bracket 54 attached to the plate 44 of the carriage. The rearward limit of travel of the carriage is determined by abutment of the rearward linear bearings 44 with the rearward pair of brackets 38 on the frame side members 12.

Adjustment of the height of the motor 46 and grinding drum 48 relative to the frame 10 is achieved by means of a mechanism which will now be described. A further vertical plate 61 is attached to the drum guard 49 and extends upwardly 7 outside the frame 10 to a level above the adjacent second frame side member portion 12b. An arm 58 is attached at a pivot 59 to the plate 61 and extends rearwardly above the second side member portion 12b. At its rearward end, the arm 58 has a jockey wheel 60 which is rotatable on the arm 58 and which rides along the upper edge of the adjacent second side member portion 12b. An adjustment screw 56 is mounted on the plate 61 in a screw-threaded socket. The lower end of the adjustment screw contacts the arm 58 and therefore determines its position relative to the plate 61. The position of the arm 58 relative to the plate 61 in turn determines the lower limit position of the grinding drum 48 relative to the frame 10 when the motor 46 and drum 48 are pivoted downwardly on the strut 43 against the bias of the spring 47.

The grinding drum 48 is shown in more detail in figures 4 and 5 of the drawings. The drum 48 is about 80 mm in diameter and has an axial length of about 76 mm. The drum 48 is made of steel and is closed at one end but open at the other to form a hollow interior. At the centre of the closed end of the drum 48 is located a mounting boss 60 by means of which the drum 48 can be attached to the output shaft of the motor 46 by a set screw or bolt (not shown).

A series of diamond cutting elements 62 are secured to the cylindrical surface of the drum 48. The diamond cutting elements 62 are arranged on a helical path with the axis of the helix coincident with the cylindrical axis of the drum 48. Each diamond cutting element is rectangular in section and curved along its length to suit the outside diameter of the grinding drum 48. The diamond cutting elements 62 comprise industrial diamonds which are set in a matrix of consistency to suit the surface to be ground. The exposure of the 1 8 diamonds during grinding is thus regulated as necessary.

The use of the machine for cutting a shallow rectangular recess in a warehouse floor surface for insertion therein of a barcode or other identification plate will now be described.

The machine is first positioned on the floor surface with the carriage at the rearward limit of its travel. The feet 24 are then adjusted in order to level the frame 10 of the machine. The motor 46, after having been connected to a suitable source of electrical power, is started. This causes rotation of the grinding drum 48. The carriage is then lowered by manual gripping of the handle 50 to an extent determined by the adjustment screw 56.

When the handle 50 is pushed down, the jockey wheel 60 contacts the frame side member 12 and the 58 pivots about its pivot 59 until it comes into contact with the adjustment screw 56. The adjustment screw 56 can be rotated manually to provide changes in the ride height of the arm 58 and thus the lower limit of movement of drum 48 relative to the frame 10.

The carriage is now pushed forward along the guide rods 32 until it has reached its forward limit of travel, when the bracket 54 contacts the end stop 52. During this movement, the grinding drum cuts a shallow rectangular recess in the floor surface 31, the width of the recess being determined by the axial length of the drum 48, the length by the length of travel of the carriage and the depth by the adjustment of the screw 56. The grinding operation can now be stopped and, if desired, repeated using a different depth of penetration in order to cut a deeper recess in a second pass across the floor surface.

For movement of the machine from one location to another, the machine can be tipped on to its forward end, so that the 9 wheels 27 make contact with the floor surface 31. The rear end member 16 of the frame now provides a convenient handle for manual gripping and guiding of the machine to a f resh location.

The recess cut in the floor by the machine is suitable for insertion therein of an identification plate, for example carrying a machine readable barcode, which can be secured in the recess by use of epoxy resin, leaving the upper machinereadable surface of the identification plate flush with the 10 floor surface.

The machine has the advantage in forming a recess as described that the use of hand-held implements such as power hammers is avoided.

Claims

CLAIMS:

1. A machine for grinding a recess in a surface, comprising frame means for being positioned in a static location relative to the surface, a rotating grinding means mounted on the frame means, drive means for causing the grinding means to rotate about an axis of rotation thereof, whereby the grinding surface of the grinding means makes grinding contact with the surface, and means for allowing movement of the grinding means relative to the frame means in at least one direction so that the grinding contact with the surface forms in the surface a recess extending in the said direction.

is

2. A machine according to claim 1, in which the grinding means is also movable relative to the frame means in a directions to vary the depth of penetration of the grinding means into the surface and thus the depth of the recess formed.

3. A machine according to claim 2, in which the grinding means is pivotally movable relative to the frame means.

4. A machine according to claim 2 or 3, having resilient biasing means for biasing the grinding means away from the surface to be ground.

5. A machine according to any of claims 2 to 4, in which the grinding means is movable relative to the frame means in the second direction between a first position, in which the grinding means is clear from the surface in which the recess is to be formed, and a second position, in which the grinding means makes grinding contact with the surface.

6. A machine according to claim 5, having means for adjustment of the second position relative to the frame means.

7. A machine according to claim 6, in which the adjustment means comprises a rolling element, the position of which relative to the grinding means can be adjusted and which makes rolling contact with the frame means during movement of the grinding means relative thereto in the direction of extent of the recess.

8. A machine according to any preceding claim, in which the means for allowing movement of the grinding means relative to the frame means allows rectilinear relative movement.

9. A machine according to any preceding claim, in which the grinding means is mounted on a carriage which is movable relative to the frame means.

10. A machine according to claim 9, in which drive means for the grinding means is also mounted on the carriage.

11. A machine according to any preceding claim, in which the extent of movement of the grinding means relative to the frame means in the direction of extent of the recess is adjustable by adjustment means.

12. A machine according to any preceding claim, including means for adjustment of the position of the frame means relative to the surface to be ground.

13. A machine according to any preceding claim, in which the frame means has at one end rotatable elements which do not contact the surface to be ground when the machine is positioned for operation but which can be brought into contact with the surface by tipping the machine into a position for movement to another place of operation.

14. A machine according to any preceding claim, in which 12 the grinding means comprises a rotatable cylinder having means allowing its mounting for rotation relative to its cylindrical axis and having cutting elements on its cylindrical surface.

15. A grinding means for use in a machine according to any preceding claim, comprising a rotatable cylinder having means allowing its mounting for rotation relative to its cylindrical axis and having cutting elements on its cylindrical surface.

16. A machine according to claim or a grinding means according to claim 10, in which the cutting elements comprise diamond.

17. A machine or grinding means according to claim 16 in which the cutting elements are arranged along a helical path around the cylindrical surface.

is

18. A machine or grinding means according to claim 17, in which each cutting element is rectangular in cross-section in the radial plane of the cylinder.

19. A machine or grinding means according to claim 17 or 18, in which cutting element is elongate in the circumferential direction of the cylinder.

20. A machine or grinding means according to any of claims 17 to 19, in which each cutting element abuts its neighbouring elements in the circumferential direction but is offset relative thereto in the axial direction.

21. A machine or grinding machine according to claim 20, in which the offset is by less than the axial extent of each element.

22. A machine for grinding a recess in a surface, substantially hereinbefore described with reference to figures 1 to 3 of the drawings.

23. A grinding drum substantially as hereinbefore 13 described with reference to figures 4 and 5 of the drawings.

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