JPH07148726A - Concrete mixer - Google Patents

Abstract

PURPOSE:To improve the mixing state of materials and prepare high quality ready-mixed concrete by a method wherein kneading is carried out so as to develop differences between the travelling speed of various materials. CONSTITUTION:Sprockets for transmitting turning force are loosely fitted to the kneading shafts 3 and 3' of a mixer. At the same time, tubular bodies 14, to each of which a plurality of oscillating arms 13 are fixed radially, are mounted integrally with the kneading shafts 3 and 3' under the condition that the sprockets 9 and 9' and the oscillating arms 13 are clamped together through elastic bodies 17. Thus, through the repeated deformation and restoration of the elastic body 17 due to the load during kneading, the oscillation to the peripheral direction is generated on the kneading shafts 3 and 3' so as to transmit the resultant oscillation to kneading blades in order to oscillatingly rotate the kneading blades for kneading materials.

Description

Detailed Description of the Invention

[0001]

The present invention relates to gravel, sand, cement,
The present invention relates to a concrete mixer for producing fresh concrete by kneading water and an admixture.

[0002]

2. Description of the Related Art A twin-screw mixer, which is one of conventional concrete mixers, has two parallel kneading shafts rotating in opposite directions in a kneading tank, and a large number of arms radially arranged on the kneading shaft. The kneading blades are fixed and attached to the tip of the arm, and the materials are kneaded by appropriately moving the materials while rotating the kneading shafts in opposite directions by a driving motor.

[0003]

However, in order to produce high-quality green concrete, it is desired that the crust of cement is uniformly formed around the gravel and sand which are kneading materials. In the twin-screw mixer, the kneading blades rotate in a certain direction at a substantially constant speed, and therefore the materials move in the same direction with the same relative speed between various materials due to the rotation of the kneading blades. In this way, the moving speed between various materials is equal, and when moving in the same direction, the chance of cement entering the gap between the gravel and sand is reduced, and it is possible to form a uniform cement shell around the gravel and sand. Had to spend enough time to knead.

In view of the above points, the present invention not only simply moves the material by the kneading blade, but also makes the mixing speed of the various materials different by the kneading blade to improve the mixing condition of the material, An object of the present invention is to provide a concrete mixer capable of producing high quality fresh concrete.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above-mentioned object, the present invention allows two parallel kneading shafts arranged in a kneading tank to be rotated in opposite directions by a driving motor so that various materials can be mixed. In a concrete mixer for kneading, a sprocket rotationally driven by a drive motor is loosely fitted to a kneading shaft, and an exciting arm is attached to the shaft end of the kneading shaft so as to project in the radial direction of the shaft. It is characterized in that and are fastened with an elastic body interposed.

[0006]

According to the present invention, when the driving motor is driven to rotate the sprocket that is loosely fitted to the kneading shaft, the sprocket is kneaded with the exciting arm while pushing the exciting arm through the elastic body. It will rotate the shaft. When the kneading load is applied to the kneading shaft as the kneading progresses,
Since the elastic body sandwiched between the excitation arm and the sprocket is rotated while being compressed and deformed, elastic force is accumulated in the elastic body. Then, when the kneading load becomes smaller than the elastic force, the elastic body suddenly returns to its original shape, so that the kneading blade at the tip of the arm of the kneading shaft jumps up in the rotating direction at a rapid speed.

By repeatedly deforming and restoring the elastic body, the kneading blades are flipped up in the direction of rotation to vibrate and hit the materials to change the moving speed of each material.
Since the moving direction is constantly changed, it is possible to increase the chances of injecting the cement between the gravel and the sand, and efficiently form a uniform cement shell around the gravel and the sand.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

Reference numeral 1 is a twin-screw mixer for kneading materials such as gravel, sand, cement, water, and an admixture to produce green concrete, and two parallel kneading shafts 3 and 3'in a kneading tank 2. And is rotatably supported by a bearing 4 fixed to the kneading tank 2. A large number of arms 5 are radially arranged on the kneading shafts 3 and 3 ', and kneading blades 6 having an appropriate angle are attached to the tips of the arms 5. Kneading shaft 3, 3 '
Gears 7 and 7'are attached to one end of the boss portion 7a,
As shown in FIG. 4, a key 8 is driven into 7a 'and the kneading shaft 3,
The gears 7 and 7'are engaged with each other so that the kneading shafts 3 and 3'are rotated at a synchronous speed.

The bosses 7a and 7a of the gears 7 and 7'are provided on the other end of the kneading shafts 3 and 3'without fixing the sprockets 9 and 9'to the kneading shafts 3 and 3'as a rotation transmission mechanism. '
It is attached loosely. Drive motors 10 and 10 'are provided on the sides of the sprockets 9 and 9', and the sprocket 1 attached to the drive motors 10 and 10 'is
1, 1'and the sprocket 9, 9'to the chain 1
The sprocket wheels 9 and 9'are rotated by driving motors 10 and 10 'which are connected by 2 and 12'.

Also, the boss portions 7a, 7'of the gears 7, 7 '
A cylinder body 1 having the excitation arm 13 is attached to a ′ by mounting a cylinder body 14 in which a plurality of excitation arms 13 are protruded in the radial direction of the axis and driving a key 15 to fix it.
4 rotates integrally with the shaft bodies 3 and 3 '.

In order to fasten the sprocket 9, 9'to the excitation arm 13 integrated with the shaft 3, 3 ',
Fixing pieces 16, 16 'are erected at positions where the sprocket 9, 9 holds the exciting arm 13, and an elastic body 1 having an appropriate elastic force between the fixing pieces 16, 16' and the exciting arm 13 is provided.
7, for example, bolts and nuts 1 by sandwiching multiple disc springs
It is concluded by 8.

Therefore, the force for rotating the sprockets 9, 9'by the driving motors 10, 10 'is transmitted to the excitation arm 13, the cylindrical body 14 via the elastic body 17,
Further, from the cylindrical body 14 to the boss portions 7a, 7a 'of the gears 7, 7'.
And finally to the shafts 3, 3.

When the driving motors 10 and 10 'are driven to rotate the sprockets 9 and 9'to knead the fresh concrete, the sprockets 9 and 9'are used for excitation while deforming the elastic body 17. The arm 13 is pushed to rotate the cylindrical body 14, and as a result, the kneading shafts 3 and 3 ′ integrated with the cylindrical body 14 can be rotated.

Then, a predetermined amount of gravel in the kneading tank 2,
When sand, cement, water, and an admixture are sequentially added to start kneading, the kneaded product becomes viscous as water spreads in the tank, and the kneading load applied to the kneading blade 6 also increases. When the load applied to the kneading blades 6 increases, this load acts in the direction to prevent the rotation of the kneading shafts 3 and 3 ', and the force to prevent the rotation is for exciting the cylindrical body 14 from the kneading shafts 3 and 3'. It extends to the arm 13.

On the other hand, the sprockets 9 and 9'fastened to the exciting arm 13 try to rotate by resisting the kneading load by the drive motors 10 and 10 '. as a result,
A load is applied to a portion of the elastic body 17 sandwiched between the excitation arm 13 of the cylindrical body 14 and the fixing pieces 16 and 16 'of the sprockets 9 and 9', and the elastic body 17 is rotated while being compressed and deformed. Become. In this embodiment, since the elastic body 17 is provided on both sides of the exciting arm 13, when one side of the elastic body 17 is in a compressed state, the other side is in an extended state.

When the elastic body 17 is compressed and deformed, elastic force is accumulated in the elastic body 17, and when the kneading load becomes smaller than this elastic force, the shape of the elastic body 17 is rapidly restored by the reaction, so that The kneading shafts 3 and 3'which are integrated with the excitation arm 13 are rotated in the rotation direction at a rapid speed, and the action causes the kneading blades 6 to jump up in the rotation direction at a rapid speed.
By repeating compression deformation and restoration of the elastic body 17 within a short period of time, this movement is transmitted to the kneading blade 6 and vibrates the kneading blade 6.

As described above, the vibration by the kneading blades 6 has a function of hitting the material, which changes the moving speed of each material to be kneaded and also changes the moving direction. It is possible to increase the number of opportunities to enter, improve the mixing condition of the materials, and manufacture high-quality ready-mixed concrete.

The size and speed of deformation and restoration of the elastic body 17 can be adjusted by appropriately selecting the size of the elastic body 17 and the strength of the elastic force. It is advisable to adopt an appropriate elastic body 17 depending on the situation. Further, since the elastic body 17 can absorb the impact caused by the biting of the material, it is preferable to select in consideration of this point. Further, although the excitation arm 13 is attached to the cylindrical body 14, the excitation arm 13 may be attached to the sprocket 9, 9'side, and various changes can be made without departing from the scope of the present invention. Of course. Further, it can be applied to a uniaxial concrete mixer.

[0020]

As described above, according to the present invention, the sprocket 9, which is rotationally driven by the drive motors 10 and 10 ',
While 9'is loosely fitted to the kneading shafts 3 and 3 ', the kneading shafts 3 and 3'
Excitation arm 1 integrated with kneading shafts 3 and 3'at the shaft end of
3, 13 'are fixed in the radial direction of the shaft, and the excitation arm 13,
Since 13 'and the sprockets 9 and 9'are fastened with the elastic body 17 interposed, the elastic body 17 is repeatedly deformed and restored during kneading to vibrate the kneading shafts 3 and 3'in the circumferential direction,
As a result, the kneading blades 6 rotate while beating the kneading materials while vibrating, changing the moving speed and the moving direction of each kneading material, and sufficiently advancing the cement between the gravel and the sand to surround the gravel and the sand. It is possible to form a uniform cement shell and produce high quality ready-mixed concrete.

[Brief description of drawings]

FIG. 1 is a front view of a concrete mixer of the present invention.

FIG. 2 is a partially omitted plan view of FIG.

FIG. 3 is an enlarged sectional view taken along the line AA of FIG.

FIG. 4 is an enlarged view of a main part of FIG. 3 with some parts omitted.

FIG. 5 is a side view of FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Biaxial mixer 3, 3 '... Kneading shaft 6 ... Kneading blade 7a, 7'a ... Gear boss 9, 9' ... Sprocket 10, 10 '... Drive motor 13 ... Excitation arm 14 ... Cylindrical body 16 , 16 '... Fixing piece 17 ... Elastic body

Claims (1)

[Claims] 1. A concrete mixer for kneading various materials by rotating two parallel kneading shafts arranged in a kneading tank in opposite directions by a driving motor, and kneading a sprocket rotationally driven by the driving motor. Concrete that is characterized in that, while being loosely fitted to the shaft, an excitation arm is attached to the shaft end of the kneading shaft so as to project in the axial radial direction, and the excitation arm and the sprocket are fastened with an elastic body interposed. Mixer.