GB2202757A

GB2202757A - Cement mixer

Info

Publication number: GB2202757A
Application number: GB08706773A
Authority: GB
Inventors: Giles Antony Walker; George Rodney Walker
Original assignee: WALKER MIXERS Ltd
Current assignee: WALKER MIXERS Ltd
Priority date: 1987-03-21
Filing date: 1987-03-21
Publication date: 1988-10-05
Anticipated expiration: 2007-03-21
Also published as: ZA881595B; GB2202757B; GB8706773D0

Abstract

A cement mixer comprises a drum 10 and a tippable support framework 11 for the drum, the drum being rotatable on the framework and being free to be lifted clear of the framework to facilitate transport or storage of the cement mixer, the drum being such that it is arrangeable to be stacked together with one or more similar drums, for example for having a handwheel which is shaped to fit together with a drum lid. The handwheel protects the drum spindle 16. The framework is provided with a retractable handle, and may have a mounting arrangement for a drive motor or i.c. engine. <IMAGE>

Description

Cement Mixers The invention relates to cement mixers.

U.K. Patents 1573606 and 1574303 describe a cement mixer having a plastics drum rotatably supported on a collapsible frame, the mixer being positionable in two stable positions, one for loading and one for discharging, the drum being rotatable by either a handwheel or a motor. We have now invented an improved version of cement mixer incorporating features which allow easier storage of a plurality of like mixers and easier operation of the mixers.

According to one aspect of the invention, a cement mixer comprises a drum and a support framework for the drum, the drum being rotatable on the framework and being free to be lifted clear of the framework to facilitate transport or storage of the cement mixer, the drum being such that it is arrangable to be stacked together with one or more similar drums.

Preferably, the drum is provided with a lid on which another drum may be stacked.

The lid is preferably shaped to fit together with part of another drum.

Preferably the drum is provided with a handwheel which fits into the shaped lid of another drum.

Preferably the drum has a spindle extending axially from the base of the drum, which spindle is insertable into a support on the framework.

Preferably the spindle is slidable into a slotted support member of the framework.

The handwheel preferably projects in the axial direction further than the spindle so that the drum can be stood squarely on its base, resting on the handwheel.

Preferably the spindle support on the framework is cranked or angled to allow it to contact the spindle without fouling on the handwheel.

According to a second aspect of the invention a cement mixer comprises a drum and a support framework for the drum, the drum being rotatable on the framework by means of a spindle projecting from the base of the drum and being free to be lifted clear of the framework to facilitate transport or storage of the cement mixer, the drum having a handle mounted on the base of the drum such that the drum may be stood squarely on the ground supported by the handle without the spindle fouling on the ground.

According to a third aspect of the invention, a cement mixer comprises a drum and a support framework for the drum, the drum being rotatable on the framework and being free to be lifted clear of the framework to facilitate transport or storage of the cement mixer, the framework being such that in one position it will support the drum in a stable manner with the mouth of the drum facing upwardly, but it can be tipped into a second position in which it will support the drum in a stable position with the mouth of the drum facing downwardly, the framework having four legs which are such that in the said one position one of the legs does not touch the ground and in the said second position another of the legs does not touch the ground, so that in each stable position the framework is supported by three legs, the cement mixer having a handle to allow easy movement of the cement mixer from one stable position to the other.

The handle is preferably attached to the framework and may be retractable.

There may be means to lock the handle in its retractable position. The means may comprise a pin engagable in a slot.

There may be means to limit the movement of the handle between its retracted and non-retracted positions.

Preferably the four legs each have a removable portion. The removable portions may b the same length.

Each leg may have a domed foot.

According to a fourth aspect of the invention, a cement mixer comprises a drum and a support framework for the drum, the drum being rotatable on the framework and being rotatable by a belt or like drive member passing around the drum, the drive member being driven by a motor secured to a pivotally mounted member of the framework and being kept under tension by an externally threaded member (e.g. a bolt) which passes through a correspondingly internally threaded member (e.g. a nut) on the pivotally mounted member and abuts a fixed piece of the framework.

Preferably the motor is arranged to slide on to the framework in one direction, the externally threaded member being engagable behind a projection to prevent the motor from moving in the opposite direction.

The motor may be mountable on an arm which is pivotable between a first position in which the motor is in an operating position, and a second position in which the motor is in a more accessible position, for example for maintenance or addition of fuel.

The externally threaded member may be engagable behind a second projection to prevent the motor from moving from the operating position to the more accessible position.

By way of example, specific embodiments of the invention will now be described, with reference to accompanying drawings, in which : Figure 1 is a perspective view of a first embodiment of cement mixer according to the invention; Figure 2 is a side view, in cross-section showing how several drums may be stacked; Figure 3 is a side view of an alternative arrangement which may used to rotate the drum; Figure 4 is a view similar to Figure 3 but showing an alternative embodiment of the invention; and Figure 5 is a view of the embodiment of Figure 4 but fitted with an internal combustion engine.

The main features of the mixer are similar to those described in U.K. Patents 1573606 and 1574303 and so only a brief description of the general workings of the mixer will be described.

Referring firstly to Figure 1, a cement mixer comprises a tubular metal framework 11 and a plastics drum 10 supportable on the frame at 28 by a spindle 16 on the base of the drum. The spindle carries a bearing which in use is slid into a slotted support on the frame 28. In use the drum also rests on two metal rollers 25 attached to the frame and the metal rollers bear on a metal band 13 around the drum to reduce the wear of the drum by the rollers.

The frame 11 has four legs 20 and four feet 21.

Only three of the four feet can touch the ground at any one time, namely the two centre feet and either the fore or the aft foot. The mixer is designed so that it is stable in both these positions. When resting on the aft foot, the drum 11 tilts upwardly, allowing the materials to be mixed to be placed in this drum. When resting on the fore foot, the drum tilts downwardly, allowing the mixed materials to be poured out. In order to facilitate the moving of the mixer to these positions, especially when a large mixer or a heavy load is used, a retractable handle 30 is provided as an extension of framework member 17a. When not in use, the handle may be pushed back into framework member 17, leaving only the T-piece 31 showing. The handle is captive in the member 17a so that the extent to which it can project is limited.

Extending around the periphery of the base of the drum 10 is a handwheel which is attached to the drum at four mounting points 32. Unlike the handwheel in U.K. Patents 1573606 and 1574303, this handwheel protrudes below the base of drum 10 and beneath the spindle 16, the reason for which will become apparent later. In order to allow free rotation of the drum, without fouling on the handwheel, the arm 27 which supports the spindle 16 is cranked. The spindle is the same as that described in the aforementioned two U.K. Patents and will not be described in detail; suffice to say that when in position the spindle allows the drum 10 to be rotated, but prevents axial movement of the drum.

Referring now to Figure 2, the Figure shows how three cement mixers can be stacked for storage.

The frame 11 of each mixer is designed to be detachable into separate pieces and these fit inside the drum 10 of the mixer. Each drum is provided with a moulded plastics lid 33. The lid has an annular groove 34 extending around its periphery and this groove 34 is shaped to receive the handwheel 15 of another mixer. Since the handwheel 15 extends below the level of the drum base and the spindle 16, several mixers may be stacked together by placing the handwheel 15 of a drum 10 in the annular groove 34 of a lid 33. In the Figure three drums are shown as stacked but there may be fewer or more than this number.

Turning now to Figure 3, there is illustrated a motor 35 which may be used instead of, or as well as, the handwheel 15 to rotate the drum. The motor 35 is rigidly attached to an arm 36 at 37. The arm 36 is pivotally attached to cross-member 18 of the framell. The drive is taken from the motor to pulley 38 and thence to a drive belt 39 which extends around the circumference of the drum. The drive belt 39 is key under tension by means of device 40. Device 40 comprises a nut 41 welded to arm 36 and a threaded bolt 42 which passes through the nut 41 and bears upon cross-member 18 of the frame 11. By screwing bolt 42 into the nut 41 the arm 36 is forced away from the cross-member 18, thus keeping the belt under tension. The motor may be electric, pneumatic or hydraulic.

There is shown part of an alternative embodiment of mixer, the view being generally similar to that shown in Figure 3 of the first embodiment. However in this embodiment the motor 43 has a casing 44 which includes a short pin 45 which can be slid into a tube 46 on the frame 47 to pivotally mount the motor on the frame 47. The casing 42 also has a bolt 48 threaded therethrough which can be tightened against a stop 49 to tension the drive belt (not shown).

Projecting from the stop 49 is a flange 50 behind which the end of the bolt 48 engages. Thus once the pin 45 has been slid into the tube 46 and the bolt 48 has been tightened, the motor cannot move in the reverse direction and so the motor is securely retained in its working position. However, when it is desired to remove the motor it can be rapidly removed without the use of tools by simply unscrewing the bolt 48, releasing the drive belt and withdrawing the pin 45 from the tube 46.

Figure 5 is a view looking in the reverse direction to Figure 4, and showing the frame 47 fitted with an internal combustion engine 51. The casing 52 of the engine 51 has a pin 53 which can be slid into a socket in an arm 54. The arm 54 has a pin 55 which can be slid into the tube 46.

The casing 52 also carries a projection 56 into which a bolt 57 is threaded. The engine 51 can rapidly be mounted without the use of tools and the bolt 57 can be tightened against a second stop 58 to tension the drive belt (not shown).

As with the arrangement shown in Figure 4, the bolt 57 engages behind a flange 59 so that the engine is securely held in position when in use.

If it is desired to move the engine 51 from the position shown in Figure 5, underneath the frame, to another, more accessible position, for example for the purpose of pouring fue] into the engine, the bolt 57 can be released, and the engine moved to the right as shown in Figure 5, with the arm 54 pivotting anti-clockwise until itis horizontal. Although it is not clearly apparent from the angle of view shown in Figure 5, the engine 51 is positioned such that it can move past the stop 58 and frame portion 47, the arm 56 being cranked to bring the bolt 57 into register with the stop 58.

Once the engine has been filled with fuel, it can readily be returned to the position shown in Figure 5 and the bolt 57 can again be tightened. The end of the bolt 57 engages behind a second flange 60 so that movement of the engine to the right is only possible when the bolt 57 has been slackened.

The invention is not restricted to the details of the foregoing embodiment. For example, the two feet 21 which are always in contact with the ground when the mixer is in use may be replaced with wheels to make movement of the mixer easier.

Alternatively, all the feet 21 may be replaced with part spherical or domed feet.

The removable portions 20 of the legs may all be constructed of the same length.

The handle 30 and frame portion 17a may be tubular, and the handle 30 may be lockable in its retracted position by rotation of the handle to engage a pin in a slot.

The portion 27 of the frame, instead of being cranked as shown in Figure 1, may be arranged to extend at an angle from the frame portion 17a to the portion 28.

Claims

1. A cement mixer comprising a drum and a support framework for the drum, the drum being rotatable on the framework and being free to be lifted clear of the framework to facilitate transport or storage of the cement mixer, the drum being such that it is arrangeable to be stacked together with one or more similar drums.

2. A cement mixer as claimed in Claim 1, in which the drum is provided with a lid on which another drum may be stacked.

3. A cement mixer as claimed in Claim 2, in which the lid is shaped to fill together with part of another drum.

4. A cement mixer as claimed in Claim 3, in which the drum is provided with a handwheel which fits into the shaped lid of another drum.

5. A cement mixer as claimed in Claim 4, in which the drum has a spindle extending axially from the base of the drum, which spindle is insertable into a support on the framework.

6. A cement mixer as claimed in Claim 5, in which the spindle is slidable into a slotted support member of the framework.

7. A cement mixer as claimed In Claim 6, in which the handwheel projects in the axial direction further than the spindle so that the drum can be stood squarely on its base, resting on the handwheei

8. A cement mixer as claimed in Claim 7, in which the spindle support on the framework is cranked or angled to allow it to contact the spindle without fouling on the handwheel.

9. A cement mixer comprising a drum and a support framework for the drum, the drum being rotatable on the framework by means of a spindle proJecting from the base of the drum and being free to be lifted clear of the framework to facilitate transport or storage of the cement mixer, the drum having a handle mounted on the base of the drum such that the drum may be stood squarely on the ground supported by the handwheel without the spindle fouling on the ground.

10. a cement mixer comprising a drum and a support framework for the drum, the drum being rotatable on the framework and being free to be lifted clear of the framework to facl I I tate transport or storage of the cement mixer, the framework being such that in one position it will support the drum in a stable manner with the mouth of the drum facing upwardly, but it can be tipped into a second position in which it will support the drum in a stable position with the mouth of the drum facing downwardly, the framework having four legs which are such that In the said one position one of the legs does not touch the ground and In the said second position another of the legs does not touch the ground, so that in each stable position the framework is supported by three legs, the cement mixer having a handle to allow easy movement of the cement mixer from one stable position to the other.

11. A cement mixer as claimed in Claim 10, in which the handle is attached to the framework.

12. A cement mixer as claimed in Claim m 10 or Claim 11, in which the handle Is retractable.

13. A cement mixer as claimed in Claim 12, in which there is means to lock the handle in its retractable position.

14. A cement mixer as claimed in Claim 13, in which the locking means comprises a pin engageable in a slot.

15. A cement mixer as claimed in any one of the Claims 12 to 13, in which there is means to limit the movement of the handle between its retracted and nonretracted positions.

16. A cement mixer as claimed in any one of Claims 10 to 15, in which the four legs each have a removable portion.

17. A cement mixer as claimed in Claim 16, in which the removable portions are the same length.

18. A cement mixer as claimed in any one of Claim 10 to is, in which each leg as a domed foot.

19. A cement mixer comprising a drum and a support framework for the drum, the drum being rotatable on the framework and being rotatable by a belt or like drive member passing around the drum, the drive member being driven by a motor secured to a pivotally mounted member of the framework and being kept under tension by an externally threaded member which passes through a correspondingly internally threaded member on the pivotally mounted member and abuts a fixed piece of the framework.

20. A cement mixer- as claimed In Claim 19, in which the motor is arranged to slide on to the framework in one direction the externally threaded member being engageabie behind a proJection to prevent the motor from moving in the opposite direction.

21. A cement mixer as claimed in Claim 19 or Claim 20, in which the motor is mountable on an arm which is pivotable between a first position in which the motor is in an operating position, and a second position in which the motor is in a more accessible position, for example for maintenance or addition or fuel.

22. A cement mixer as claimed in Claim 21, when dependent on Claim 20, in which the externally threaded member is engageab le behind a second projection to prevent the motor from moving from the operating position to the more accessible position.

23. A cement mixer constructed and arranged substantially as herein described with reference to the accompanying drawings.