阅读说明：本技术 一种自适应式撒布车及撒布方法 (Self-adaptive spreading vehicle and spreading method ) 是由 王保平 王永娟 孙芹 管志光 李作丽 于 2021-08-04 设计创作，主要内容包括：本发明公开了一种自适应式撒布车及撒布方法,包括车体,车体连接有横梁,横梁连接有若干个喷头,车体连接有横向导杆,横向导杆滑动套设有横向导套,横向导杆通过第二弹簧与横向导套相连；横向导套连接有竖直方向设置的挡板,挡板一侧转动设置有与路沿石相适配的横向导轮,挡板还连接有横向设置的齿条和固定板；喷头内滑动连接有调整杆,调整杆上端穿出喷头连接有丝杆,丝杆配合设置有丝母,丝杆上端连接有齿轮,齿轮与齿条相啮合；固定板开设有限位槽,丝母连接有滑动键,滑动键滑动设置在限位槽内且沿水平方向滑动。本发明可自动根据路面的宽度以及起伏程度,自动调整撒布的范围,起到解决材料,防止出现二次撒布或者后续清理不便的问题。(The invention discloses a self-adaptive spreading vehicle and a spreading method, wherein the self-adaptive spreading vehicle comprises a vehicle body, the vehicle body is connected with a cross beam, the cross beam is connected with a plurality of spray heads, the vehicle body is connected with a transverse guide rod, the transverse guide rod is slidably sleeved with a transverse guide sleeve, and the transverse guide rod is connected with the transverse guide sleeve through a second spring; the transverse guide sleeve is connected with a baffle arranged in the vertical direction, one side of the baffle is rotatably provided with a transverse guide wheel matched with the curb stone, and the baffle is also connected with a rack and a fixing plate which are arranged transversely; an adjusting rod is connected in the spray head in a sliding manner, the upper end of the adjusting rod penetrates through the spray head to be connected with a screw rod, a nut is arranged on the screw rod in a matching manner, and a gear is connected to the upper end of the screw rod and meshed with the rack; the fixed plate is provided with a limiting groove, the nut is connected with a sliding key, and the sliding key is arranged in the limiting groove in a sliding mode and slides along the horizontal direction. The invention can automatically adjust the spreading range according to the width and the undulation degree of the road surface, solves the problem of material and prevents the occurrence of secondary spreading or inconvenient subsequent cleaning.)

1. The self-adaptive spreading vehicle comprises a vehicle body (11), wherein the vehicle body (11) is connected with a cross beam (21), the cross beam (21) is fixedly connected with a plurality of spray heads (12), and the self-adaptive spreading vehicle is characterized in that the vehicle body (11) is fixedly connected with a transverse guide rod (10), the transverse guide rod (10) is slidably sleeved with a transverse guide sleeve (8), and the transverse guide rod (10) is connected with the transverse guide sleeve (8) through a second spring (9); the transverse guide sleeve (8) is connected with a baffle (4) arranged in the vertical direction, one side of the baffle (4) is rotatably provided with a transverse guide wheel (3) matched with the curbstone (2), and the baffle (4) is also connected with a rack (14) and a fixing plate (15) which are transversely arranged; an adjusting rod (16) is connected in the spray head (12) in a sliding manner, the upper end of the adjusting rod (16) penetrates through the spray head (12) to be connected with a screw rod (20), a screw nut (22) is arranged on the screw rod (20) in a matching manner, a gear (13) is connected to the upper end of the screw rod (20), and the gear (13) is meshed with the rack (14); the fixing plate (15) is provided with a limiting groove (19), the screw nut (22) is connected with a sliding key (24), and the sliding key (24) is arranged in the limiting groove (19) in a sliding mode and slides along the horizontal direction.

2. An adaptive spreading vehicle according to claim 1, wherein the second spring (9) is sleeved on the transverse guide rod (10), one end of the second spring (9) is connected with the transverse guide rod (10), and the other end of the second spring (9) is connected with the transverse guide sleeve (8); the device also comprises a limiting mechanism, and in an initial state, the limiting mechanism is used for moving the transverse guide sleeve (8), so that the second spring (9) is in a compressed state.

3. An adaptive spreading vehicle according to claim 1, wherein a liquid chamber (17) is formed in the spraying head (12), the spraying head (12) comprises a nozzle for spreading, a gap is reserved between the nozzle and the adjusting rod (16), the adjusting rod (16) is slidably arranged in the liquid chamber (17), the upper end of the adjusting rod (16) penetrates through the liquid chamber (17) to be connected with the screw rod (20), and a sealing ring (18) is arranged at the joint of the adjusting rod (16) and the liquid chamber (17).

4. An adaptive spreading vehicle according to claim 3, wherein a pressure mechanism is connected to the spray head (12) for driving the liquid flow in the liquid chamber (17) to pass the liquid out through the nozzle.

5. The self-adaptive spreading vehicle according to claim 1, wherein the transverse guide sleeve (8) is fixedly connected with a vertical guide sleeve (7), a vertical guide rod (23) is slidably connected in the vertical guide sleeve (7), the vertical guide rod (23) is connected with the vertical guide sleeve (7) through a first spring (6), the vertical guide rod (23) is connected with the baffle (4), the bottom end of the baffle (4) is rotatably connected with a plurality of travelling wheels (1), and the height of the rack (14) is greater than that of the gear (13).

6. An adaptive spreading vehicle according to claim 5, wherein the first spring (6) is sleeved on the vertical guide rod (23), one end of the first spring (6) is connected with the vertical guide rod (23), and the other end of the first spring (6) is connected with the vertical guide sleeve (7).

7. An adaptive spreading vehicle according to claim 5, wherein the vertical guide sleeve (7) is connected with the rack (14), the vertical guide rod (23) is connected with the fixing plate (15) through an L-shaped plate (5), and the nut (22) is connected with the cross beam (21) in a sliding manner and slides along the vertical direction.

8. A method of dispensing, using an adaptive spreader according to any of claims 2 to 7, comprising the steps of:

s1, when the vehicle body (11) moves on the road, the limiting mechanism is released, the limiting mechanism does not limit the movement of the transverse guide sleeve (8), the transverse guide wheel (3) is contacted with the road edge stone (2) on one side of the road under the action of the second spring (9), and the transverse guide sleeve (8) moves for a corresponding distance along the length direction of the transverse guide rod (10);

s2: the transverse guide sleeve (8) moves to drive the rack (14) to move towards the direction far away from the vehicle body (11), the rack (14) drives the gear (13) to rotate, the gear (13) drives the screw rod (19) to rotate, and the screw rod (19) drives the adjusting rod (16) to move downwards, so that the spreading area of the spray head (12) is increased, and in the process, the sliding key (24) slides in the limiting groove (19) to drive the screw nut (22) to slide in the horizontal direction.

9. The spreading method of the self-adaptive spreading vehicle according to claim 8, wherein when the self-adaptive spreading vehicle advances on a rough road, the rough road drives the traveling wheels (1) to move upwards to drive the baffle (4) to move upwards, the vertical guide rod (23) moves upwards in the vertical guide sleeve (7), the vertical guide rod (23) drives the fixing plate (15) to move upwards, the nut (22) is driven to move upwards by the sliding key (24) under the action of the limiting groove (19), the nut (22) drives the screw rod (20) to move upwards, the screw rod (20) drives the adjusting rod (16) to move upwards, so that the spreading area of the spray head (12) is reduced, and the gear (13) and the rack (14) slide relatively in the process.

10. The method as claimed in claim 8, wherein in step S2, when the adjusting rod (16) moves downward, the distance from the adjusting rod (16) to the nozzle decreases, so that when the pressure mechanism drives the liquid in the liquid chamber (17) to flow, the liquid is sprayed from the nozzle, and the spreading area increases.

Technical Field

The invention relates to the technical field of road construction, in particular to a self-adaptive spreading vehicle and a spreading method.

Background

At present, before the construction of an asphalt surface layer, in order to reduce the waste of asphalt mixture and environmental pollution caused by the edge cutting of an asphalt pavement, the construction of concrete projects such as a curb stone, a water drainage groove, a hard road shoulder, a concrete guardrail and the like is generally adopted. In the process of pavement surface layer construction, the permeable layer, the seal layer and the adhesive layer are prevented from being scattered. Concrete projects such as kerbs, torrent chutes, hard road shoulders, concrete guardrails and the like are polluted, and geotechnical cloth, plastic films and the like are used for covering in the traditional method, so that the labor and material waste is increased.

When spreading permeable course, seal, adhesion coating, carry out the protection in-process to concrete engineering such as curb in advance, torrent groove, hard curb, concrete guardrail, owing to spray the impact force and cause the pollution more or less, the extravagant manpower and materials of later stage clearance, influence concrete appearance quality, moreover the in-process of spreading because dispensing device can not adjust the distance apart from curb, therefore cause the spreading can not arrive the border, cause secondary work very easily, and be unfavorable for subsequent clearance work.

Disclosure of Invention

In order to solve the problems in the prior art, a self-adaptive spreading vehicle and a spreading method are provided.

The technical scheme adopted by the invention for solving the technical problems is as follows:

the invention provides a self-adaptive spreading vehicle which comprises a vehicle body, wherein the vehicle body is connected with a cross beam, the cross beam is fixedly connected with a plurality of spray heads, the vehicle body is fixedly connected with a transverse guide rod, the transverse guide rod is slidably sleeved with a transverse guide sleeve, and the transverse guide rod is connected with the transverse guide sleeve through a second spring; the transverse guide sleeve is connected with a baffle arranged in the vertical direction, one side of the baffle is rotatably provided with a transverse guide wheel matched with the curb stone, and the baffle is also connected with a rack and a fixing plate which are arranged transversely; an adjusting rod is connected in the spray head in a sliding manner, the upper end of the adjusting rod penetrates out of the spray head to be connected with a screw rod, a nut is arranged on the screw rod in a matching manner, a gear is connected to the upper end of the screw rod, and the gear is meshed with the rack; the fixed plate is provided with a limiting groove, the nut is connected with a sliding key, and the sliding key is arranged in the limiting groove in a sliding mode and slides along the horizontal direction.

Preferably, the second spring is sleeved on the transverse guide rod, one end of the second spring is connected with the transverse guide rod, and the other end of the second spring is connected with the transverse guide sleeve; the limiting mechanism is used for moving the transverse guide sleeve in an initial state, so that the second spring is in a compressed state.

Preferably, a liquid cavity is formed in the spray head, the spray head comprises a nozzle for spreading, a gap is reserved between the nozzle and the adjusting rod, the adjusting rod is arranged in the liquid cavity in a sliding mode, the upper end of the adjusting rod penetrates out of the liquid cavity and is connected with the screw rod, and a sealing ring is arranged at the joint of the adjusting rod and the liquid cavity.

Preferably, the spray head is connected with a pressure mechanism, and the pressure mechanism is used for driving the liquid in the liquid cavity to flow so as to enable the liquid to be sprayed out through the spray nozzle.

Preferably, the transverse guide sleeve is fixedly connected with a vertical guide sleeve, a vertical guide rod is slidably connected in the vertical guide sleeve, the vertical guide rod is connected with the vertical guide sleeve through a first spring, the vertical guide rod is connected with the baffle, the bottom end of the baffle is rotatably connected with a plurality of travelling wheels, and the height of the rack is greater than that of the gear.

Preferably, the first spring is sleeved on the vertical guide rod, one end of the first spring is connected with the vertical guide rod, and the other end of the first spring is connected with the vertical guide sleeve.

Preferably, the vertical guide sleeve is connected with the rack, the vertical guide rod is connected with the fixed plate through an L-shaped plate, and the screw is connected with the cross beam in a sliding mode and slides along the vertical direction.

The invention also provides a spreading method, which comprises the following steps:

s1, when the vehicle body walks on the road surface, the limiting mechanism is released, the limiting mechanism does not limit the movement of the transverse guide sleeve any more, the transverse guide wheel is contacted with the road edge stone on one side of the road surface under the action of the second spring, and the transverse guide sleeve moves for a corresponding distance along the length direction of the transverse guide rod;

s2: the transverse guide sleeve moves to drive the rack to move towards the direction far away from the vehicle body, the rack drives the gear to rotate, the gear drives the screw rod to rotate, and the screw rod drives the adjusting rod to move downwards, so that the spreading area of the spray head is increased, and in the process, the sliding key slides in the limiting groove to drive the screw nut to slide in the horizontal direction.

Preferably, when advancing on the undulant road surface, the undulant road surface drives walking wheel rebound, and then drives baffle rebound, vertical guide arm rebound in vertical guide pin bushing, vertical guide arm drives the fixed plate rebound, under the effect of spacing groove, through the nut rebound of sliding key drive, the nut drives the lead screw rebound, the lead screw drives the adjusting lever rebound to make shower nozzle spread area reduce, at this in-process, relative slip takes place for gear and rack.

Preferably, in step S2, when the adjusting rod moves downward, the distance from the adjusting rod to the nozzle is decreased, so that when the pressure mechanism drives the liquid in the liquid chamber to flow, the dispensing area is increased after the liquid is ejected through the nozzle.

Compared with the prior art, the invention has the beneficial effects that:

1. the automatic road width adaptation device can automatically adapt to the width of the road surface according to the difference of the width of the road edge stones, when a wider road surface is met, the rack drives the screw rod to rotate through the gear, and the screw rod can drive the adjusting rod to move downwards because the screw nut can only slide in the horizontal direction but can not rotate, so that the distance from the adjusting rod to the nozzle is reduced, the spreading area is increased, the operation is simple, the structure is reasonable, the automatic road width adaptation device is economical and practical, manual adjustment is not needed, the automatic road width adaptation device can automatically adapt to the width of the road surface, materials are saved, and secondary spreading is not needed.

2. The invention is also provided with the travelling wheels, when the vehicle walks on a rough road, the travelling wheels upwards drive the fixing plate to upwards move, so the screw can be driven to upwards move through the limiting groove, the screw cannot rotate at the moment, the screw rod is driven to have a tendency of rotating, and at the moment, the gear is meshed with the rack, and the screw rod cannot rotate, so when the screw ascends, the screw rod can be driven to upwards move, the adjusting rod is driven to upwards move, the distance between the adjusting rod and the nozzle is increased, the spreading area is reduced, the spreading area is adaptive to the rough road, the material is saved, the excessive spreading material is prevented, the subsequent cleaning work is not needed, the manpower and material resources are greatly saved, the vehicle is economical and practical, and the vehicle is suitable for popularization.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is an overall front view of the present invention;

FIG. 2 is an enlarged view of the portion A in FIG. 1;

FIG. 3 is an overall side view of the present invention;

FIG. 4 is an enlarged view of the portion B of FIG. 3;

fig. 5 is an overall top view of the invention.

Description of reference numerals:

1, a traveling wheel; 2, a curb stone; 3, a transverse guide wheel; 4, a baffle plate; a 5L-shaped plate; 6 a first spring; 7, a vertical guide sleeve; 8, a transverse guide sleeve; 9 a second spring; 10 a transverse guide rod; 11 a vehicle body; 12, a spray head; 13 gears; 14 racks; 15 fixing the plate; 16 an adjusting rod; 17 a liquid chamber; 18 sealing rings; 19 a limiting groove; 20, a screw rod; 21 a cross beam; 22 a nut; 23 vertical guide rods; 24 sliding the key.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

As shown in fig. 1 to 5, the present embodiment provides an adaptive spreading vehicle, which includes a vehicle body 11, wherein the vehicle body 11 is connected with a cross beam 21, and the cross beam 21 is fixedly connected with a plurality of nozzles 12. The vehicle body 11 is a spreading vehicle for spreading work, the beam 21 is fixedly connected with the vehicle body 11, a plurality of spray heads 12 can be arranged according to actual requirements, and 4 spray heads 12 are arranged and are all fixedly connected with the beam 21.

The vehicle body 11 is fixedly connected with a transverse guide rod 10, the transverse guide rod 10 is slidably sleeved with a transverse guide sleeve 8, and the transverse guide rod 10 is connected with the transverse guide sleeve 8 through a second spring 9. The second spring 9 is sleeved on the transverse guide rod 10, one end of the second spring 9 is fixedly connected with the transverse guide rod 10, and the other end of the second spring 9 is fixedly connected with the transverse guide sleeve 8; the device further comprises a limiting mechanism, and in an initial state, the limiting mechanism is used for moving the transverse guide sleeve 8, so that the second spring 9 is in a compressed state.

The second spring 9 is arranged outside the transverse guide sleeve 8, and the transverse guide sleeve 8 is arranged in the horizontal direction, so that the transverse guide sleeve 8 can freely slide along the length direction of the transverse guide rod 10. Limiting mechanism can be for the limiting plate with automobile body 11 fixed connection, and it is connected with the stopper to rotate on the limiting plate, has seted up the constant head tank in the horizontal guide pin bushing 8, when the stopper rotated in the constant head tank for the position of horizontal guide pin bushing 8 keeps not right relatively, thereby plays spacing effect to the removal of horizontal guide pin bushing 8, and second spring 9 is in compression state this moment. In this kind of mode of setting, the distance of 8 distance automobile bodies 11 of horizontal guide sleeve can be shortened, plays the effect of being convenient for to accomodate, reduces automobile bodies 11's horizontal open area to adapt to various narrow and small highway sections, and when the spreader normal walking, can not influence the normal driving of other vehicles.

The transverse guide sleeve 8 is connected with a baffle 4 arranged in the vertical direction, the baffle 4 acts on the spreading action of the spray head 12 to play a role in shielding, when the spray head 12 is sprayed out of a large area, the material spraying range is too large, and the cost and time for subsequent cleaning of operators are saved.

Baffle 4 one side is rotated and is provided with the lateral guide wheel 3 with curb stone 2 looks adaptation, and curb stone 2 is the conventional setting of road surface both sides promptly, and lateral guide wheel 3 and curb stone 2 rolling contact. The baffle 4 is also connected with a rack 14 and a fixed plate 15 which are transversely arranged; an adjusting rod 16 is connected in the spray head 12 in a sliding manner, the upper end of the adjusting rod 16 penetrates through the spray head 12 to be connected with a screw rod 20, a screw nut 22 is arranged on the screw rod 20 in a matching manner, a gear 13 is connected at the upper end of the screw rod 20, and the gear 13 is meshed with a rack 14; the fixing plate 15 is provided with a limiting groove 19, the nut 22 is connected with a sliding key 24, and the sliding key 24 is slidably arranged in the limiting groove 19 and slides along the horizontal direction.

The limiting groove 19 is used for limiting the movement of the sliding key 24, so that the sliding key 24 can only slide along the length direction of the limiting groove 19 and cannot rotate, the nut 22 can only slide freely in the horizontal direction and cannot rotate, and the limiting groove 19 is also used for providing a sufficient movement space for the movement of the sliding key 24 when the fixing plate 15 moves in the horizontal direction.

A liquid cavity 17 is formed in the spray head 12, the spray head 12 comprises a spray nozzle for spreading, a gap is reserved between the spray nozzle and the adjusting rod 16, the adjusting rod 16 is arranged in the liquid cavity 17 in a sliding mode, the upper end of the adjusting rod 16 penetrates through the liquid cavity 17 to be connected with a screw rod 20, and a sealing ring 18 is arranged at the connecting position of the adjusting rod 16 and the liquid cavity 17.

A pressure mechanism is connected to the head 12 for driving a flow of liquid in the liquid chamber 17 so as to cause the liquid to be ejected through the nozzles.

Pressure mechanism adopts conventional device, shower nozzle 12 has the storage bucket through the conveying pipe intercommunication, storage bucket and 11 fixed connection of automobile body, the storage bucket still is connected with the delivery pump, when normal use, in the delivery pump carries shower nozzle 12 with the material in the storage bucket, pressure mechanism is the material pressure boost in the liquid chamber 17 simultaneously for the material blowout in the liquid chamber 17, and the distance of adjusting lever 16 apart from the nozzle is less, and it is bigger to make nozzle spun area, realizes the adjustment of spreading area.

Horizontal guide pin bushing 8 fixedly connected with vertical guide pin bushing 7, sliding connection has vertical guide rod 23 in vertical guide pin bushing 7, vertical guide rod 23 links to each other with vertical guide pin bushing 7 through first spring 6, vertical guide rod 23 links to each other with baffle 4, baffle 4 bottom is rotated and is connected with a plurality of walking wheel 1, rack 14 height is greater than gear 13 height, and rack 14's height is enough big, in order to adapt to the ground of different undulation degree, make gear 13 have sufficient sliding space relative to rack 14, and when gear 13 upwards slided, gear 13 and rack 14 are in the state of meshing all the time.

The first spring 6 is sleeved on the vertical guide rod 23, one end of the first spring 6 is fixedly connected with the vertical guide rod 23, the other end of the first spring 6 is fixedly connected with the vertical guide sleeve 7, and the first spring 6 is arranged on the outer side of the vertical guide sleeve 7.

The vertical guide sleeve 7 is connected with the rack 14, the vertical guide rod 23 is connected with the fixed plate 15 through the L-shaped plate 5, and the screw 22 is connected with the cross beam 21 in a sliding mode and slides along the vertical direction.

In addition, since the nut 22 can only slide in the horizontal direction and cannot rotate, when the nut 22 moves, the nut 22 drives the screw rod 20 to rotate, and therefore the gear 13 and the rack 14 are in a meshed state, the rotation trend drives the rack 14 to move in the direction away from the vehicle body 11, and the curb 2 is already in contact with the transverse guide wheel 3, so that the rack 14 cannot move in the direction away from the vehicle body 11, the position of the rack 14 is kept relatively fixed, and the gear 13 cannot rotate.

When the screw 22 ascends, the screw rod 20 is driven to move upwards, so that the adjusting rod 16 is driven to move upwards, the distance between the adjusting rod 16 and the nozzle is increased, the spreading area is reduced, the spread area is adaptive to the fluctuated ground, the material is saved, the spread material is prevented from being too much, the follow-up cleaning work is not needed, the manpower and material resources are greatly saved, and the device is economical and practical and is suitable for popularization.

The invention also provides a spreading method, and the self-adaptive spreading vehicle adopting the embodiment comprises the following steps:

s1, when the vehicle body 11 walks on the road surface, the limiting mechanism is released, the limiting mechanism does not limit the movement of the transverse guide sleeve 8 any more, the transverse guide wheel 3 is contacted with the road edge stone 2 on one side of the road surface under the action of the second spring 9, and the transverse guide sleeve 8 moves for a corresponding distance along the length direction of the transverse guide rod 10;

s2: the transverse guide sleeve 8 moves to drive the rack 14 to move in the direction far away from the vehicle body 11, the rack 14 drives the gear 13 to rotate, the gear 13 drives the screw rod 19 to rotate, the screw rod 19 drives the adjusting rod 16 to move downwards, the spreading area of the spray head 12 is increased, and in the process, the sliding key 24 slides in the limiting groove 19 to drive the screw nut 22 to slide in the horizontal direction.

When the sprayer moves forwards on a rough road, the rough road drives the traveling wheels 1 to move upwards, the baffle 4 is further driven to move upwards, the vertical guide rod 23 moves upwards in the vertical guide sleeve 7, the vertical guide rod 23 drives the fixing plate 15 to move upwards, the screw nut 22 is driven to move upwards through the sliding key 24 under the action of the limiting groove 19, the screw nut 22 drives the screw rod 20 to move upwards, the screw rod 20 drives the adjusting rod 16 to move upwards, and therefore the spreading area of the sprayer 12 is reduced, in the process, the gear 13 and the rack 14 slide relatively, and the gear 13 and the rack 14 are always in a meshed state.

In step S2, when the adjusting rod 16 moves downward, the distance from the adjusting rod 16 to the nozzle decreases, so that the liquid is sprayed from the nozzle when the pressure mechanism drives the liquid in the liquid chamber 17 to flow, and the spreading area increases.

It should be noted that, the transverse guide wheel 3 of the present invention can automatically adapt to the width of the road surface according to the difference of the width of the road edge stone 2, when a wide road surface is encountered, the rack 14 drives the screw rod 20 to rotate through the gear 13, and because the screw 22 can only slide in the horizontal direction but cannot rotate, the screw rod 20 can drive the adjusting rod 16 to move downwards, so that the distance from the adjusting rod 16 to the nozzle is reduced, thereby increasing the spreading area, having simple operation, reasonable structure, economy and practicality, and without manual adjustment, the width of the road surface can be automatically adapted, saving materials and without secondary spreading.

While embodiments of the invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.