阅读说明：本技术 一种自动调节等分轴距的多轴调节器 (Multi-shaft adjuster capable of automatically adjusting equal-divided wheelbase ) 是由 章君巧 于 2021-07-30 设计创作，主要内容包括：本发明公开了一种自动调节等分轴距的多轴调节器,包括由上至下依次同轴设置的多轴器、上等分直槽滑道板和等分展开板,多轴器的下端面设有数个沿周向等距排布的轴,且每个轴通过万向节均连接有转轴,上等分直槽滑道板的下端面固定有导向环,且上等分直槽滑道板的上端面的中心处固定有用于驱动等分展开板转动的带减速器电机,上等分直槽滑道板开设有数个与转轴位置一一对应的上直槽,等分展开板开设有数个与转轴位置一一对应的弧形槽,转轴依次贯穿上直槽和弧形槽,且转轴可以沿着上直槽和弧形槽移动。本发明设计合理,结构简单,操作方便,实现各等分轴的快速准确定位,省时高效,使用灵活度高,实用性强,具有推广价值。(The invention discloses a multi-axis regulator capable of automatically regulating equal-divided axial distance, which comprises a multi-axis device, an equal-divided straight-groove slideway plate and an equal-divided expansion plate, wherein the multi-axis device, the equal-divided straight-groove slideway plate and the equal-divided expansion plate are coaxially arranged from top to bottom in sequence, a plurality of shafts are arranged on the lower end surface of the multi-axis device at equal intervals along the circumferential direction, each shaft is connected with a rotating shaft through a universal joint, a guide ring is fixed on the lower end surface of the equal-divided straight-groove slideway plate, a motor with a speed reducer for driving the equal-divided expansion plate to rotate is fixed in the center of the upper end surface of the equal-divided straight-groove slideway plate, the equal-divided straight-groove slideway plate is provided with a plurality of upper straight grooves which are in one-to-one correspondence with the positions of the rotating shafts, the equal-divided expansion plate is provided with a plurality of arc grooves which are in one-to-one correspondence with the positions of the rotating shafts, the rotating shafts sequentially penetrate through the upper straight grooves and the arc grooves, and the rotating shafts can move along the upper straight grooves and the arc grooves. The positioning device is reasonable in design, simple in structure, convenient to operate, time-saving, efficient, high in use flexibility and practicability and has popularization value, and the equal split shafts are quickly and accurately positioned.)

1. The utility model provides an automatic adjust multi-axis regulator of partition wheel base which characterized in that: including the multiaxis ware, the last minute straight flute slideway board and the partition expansion board of coaxial setting in proper order from top to bottom, multiaxis ware and last minute straight flute slideway board fixed connection, the lower terminal surface of multiaxis ware be equipped with the several and follow the axle that circumference equidistance was arranged, and every axle all is connected with the pivot through the universal joint, the lower terminal surface of last minute straight flute slideway board be fixed with the guide ring, wherein the partition expansion board is rotatable locates in the guide ring, and the center department of the up end of last minute straight flute slideway board is fixed with and is used for driving partition expansion board pivoted and takes the reduction gear motor, last minute straight flute slideway board seted up several and pivot position one-to-one last straight flute, and go up the straight flute and radially extend, partition expansion board set up the arc wall of several and pivot position one-to-match, and the arc wall is arranged along circumference equidistance, the pivot run through straight flute and arc wall in proper order, and the rotating shaft can move along the upper straight slot and the arc-shaped slot.

2. A multi-axis adjuster for automatically adjusting equally-spaced wheelbases as claimed in claim 1, wherein: the motor with the speed reducer is a stepping motor with the speed reducer or a servo motor with the speed reducer.

3. A multi-axis adjuster for automatically adjusting equally-spaced wheelbases as claimed in claim 1, wherein: the motor with the speed reducer is connected with a control system through a control cable.

4. A multi-axis adjuster for automatically adjusting equally-spaced wheelbases as claimed in claim 1, wherein: the output shaft of the motor with the speed reducer can be connected with the equal-division expansion plate through gear transmission or synchronous belt transmission.

5. A multi-axis adjuster for automatically adjusting equally-spaced wheelbases as claimed in claim 1, wherein: the lower end face of the equal-division straight-groove slideway plate is fixedly provided with two locking cylinders which are symmetrically arranged on two sides of the guide ring, a locking strip is arranged below the guide ring, two ends of the locking strip are respectively connected with output ends of the two locking cylinders, and two locking blocks are arranged on one side of the locking strip, which faces the equal-division unfolding plate.

6. A multi-axis adjuster for automatically adjusting the split axle base according to claim 5, wherein: the lower equal-division straight-groove slideway plate is arranged in the guide ring and below the equal-division expansion plate, the lower equal-division straight-groove slideway plate can move up and down in the guide ring, the lower equal-division straight-groove slideway plate is connected with the two locking blocks, the lower equal-division straight-groove slideway plate is provided with a plurality of lower straight grooves which are in one-to-one correspondence with the positions of the rotating shafts, the lower straight grooves extend along the radial direction, and the rotating shafts penetrate through the lower straight grooves and can move along the lower straight grooves.

7. A multi-axis adjuster for automatically adjusting equally-spaced wheelbases as claimed in claim 1, wherein: the rotating shaft is provided with a needle bearing, and the outer side of the needle bearing is sleeved with an upper straight groove guide sleeve capable of moving along an upper straight groove, an arc-shaped guide sleeve capable of moving along an arc-shaped groove and a lower straight groove guide sleeve capable of moving along a lower straight groove.

8. A multi-axis adjuster for automatically adjusting equally-spaced wheelbases as claimed in claim 1, wherein: thrust ball bearings are arranged at the upper end and the lower end of the needle bearing on the rotating shaft, and a disc spring and a locking retainer ring are sequentially arranged at the upper end of the rotating shaft above the needle bearing from bottom to top.

9. A multi-axis adjuster for automatically adjusting equally-spaced wheelbases as claimed in claim 1, wherein: the arc-shaped groove adopts oblique lines or curved lines.

10. A multi-axis adjuster for automatically adjusting equally-spaced wheelbases as claimed in claim 9, wherein: the curve is an arc line or an involute.

Technical Field

The invention belongs to the technical field of machining, and particularly relates to a multi-axis regulator capable of automatically regulating equal axle distance.

Background

At present, shell connection of products such as motors, water pumps and the like generally adopts trisection, quartesion and sextusion through holes and threads for connection, and in the structures, the trisection holes need to be drilled, tapped and the like for mechanical processing. In order to reduce the main inventory, most enterprises choose to process according to orders, so that a small-batch and multi-specification production mode is created, when the equally divided holes are processed, the production efficiency is higher than that of one processing by simultaneously processing the connecting holes on the circumference, and the small-batch and multi-specification production mode is completed on one device, so that the requirements of various manufacturers are met. Rapid adjustment of the pitch of the evenly divided holes in each diameter in production is an urgent need.

At present, the position of each shaft of a multi-shaft device with fixed hole positions on the market is fixed after the manufacturing is finished, the hole distance cannot be adjusted, and only N or all the shafts can be selected from the existing positions. The relative position of the shaft of the multi-shaft device at the fixed hole position is fixed and cannot be adjusted, and the multi-shaft device needs to be integrally replaced when different products are processed, so that the cost is high, the replacement is time-consuming and impractical.

Another type of adjustable multi-axis device in the market at present is that the position of each hole is fixed on a disc or square plate through the screw, and the bolt moving position is loosened through the manual work, and the fixed position precision is difficult to guarantee after moving, and the regulation takes time, and the operation is inconvenient. The adjustable multi-axis device loosens the bolt moving position through manual work, and the fixed position precision is difficult to guarantee after removing, and adjusts and take time, and the operation is inconvenient.

Disclosure of Invention

The present invention is directed to a multi-axis adjuster for automatically adjusting equal axle distances to solve the above-mentioned problems of the prior art.

In order to achieve the purpose, the invention provides the following technical scheme: the utility model provides an automatic multi-axis regulator of partition wheel base of adjusting which the structural feature lies in: including the multiaxis ware, the last minute straight flute slideway board and the partition expansion board of coaxial setting in proper order from top to bottom, multiaxis ware and last minute straight flute slideway board fixed connection, the lower terminal surface of multiaxis ware be equipped with the several and follow the axle that circumference equidistance was arranged, and every axle all is connected with the pivot through the universal joint, the lower terminal surface of last minute straight flute slideway board be fixed with the guide ring, wherein the partition expansion board is rotatable locates in the guide ring, and the center department of the up end of last minute straight flute slideway board is fixed with and is used for driving partition expansion board pivoted and takes the reduction gear motor, last minute straight flute slideway board seted up several and pivot position one-to-one last straight flute, and go up the straight flute and radially extend, partition expansion board set up the arc wall of several and pivot position one-to-match, and the arc wall is arranged along circumference equidistance, the pivot run through straight flute and arc wall in proper order, and the rotating shaft can move along the upper straight slot and the arc-shaped slot.

Preferably, the motor with the speed reducer is a stepping motor with the speed reducer or a servo motor with the speed reducer.

Preferably, the motor with the speed reducer is connected with a control system through a control cable.

Preferably, the output shaft of the motor with the speed reducer can be connected with the equal spreading plate through gear transmission or synchronous belt transmission.

Preferably, two locking cylinders symmetrically arranged on two sides of the guide ring are fixed on the lower end surface of the equal-division straight-groove slideway plate, a locking strip is arranged below the guide ring, two ends of the locking strip are respectively connected with output ends of the two locking cylinders, and two locking blocks are arranged on one side of the locking strip, which faces the equal-division unfolding plate.

Preferably, a lower equal division straight groove slide way plate is arranged below the equal division expansion plate in the guide ring, wherein the lower equal division straight groove slide way plate can move up and down in the guide ring, the lower equal division straight groove slide way plate is connected with the two locking blocks, the lower equal division straight groove slide way plate is provided with a plurality of lower straight grooves which are in one-to-one correspondence with the positions of the rotating shafts, the lower straight grooves extend along the radial direction, and the rotating shafts penetrate through the lower straight grooves and can move along the lower straight grooves.

Preferably, the rotating shaft is provided with a needle bearing, and the outer side of the needle bearing is sleeved with an upper straight groove guide sleeve capable of moving along the upper straight groove, an arc-shaped guide sleeve capable of moving along the arc-shaped groove and a lower straight groove guide sleeve capable of moving along the lower straight groove.

Preferably, thrust ball bearings are arranged at the upper end and the lower end of the needle bearing on the rotating shaft, and a disc spring and a locking retainer ring are sequentially arranged at the upper end of the rotating shaft above the needle bearing from bottom to top.

Preferably, the arc-shaped groove adopts oblique lines or curved lines.

Preferably, the curve is a circular arc or an involute curve.

Compared with the prior art, the positioning device has the advantages of reasonable design, simple structure, convenience in operation, time saving, high efficiency, high use flexibility, strong practicability and popularization value, and realizes quick and accurate positioning of each equal split shaft.

Drawings

FIG. 1 is a first perspective view of the present invention;

FIG. 2 is a schematic perspective view of the present invention;

FIG. 3 is a bottom view of the present invention;

FIG. 4 is a sectional view taken along line A-A of FIG. 3;

FIG. 5 is an enlarged view of a portion of FIG. 3;

FIG. 6 is a sectional view taken along line B-B of FIG. 3;

FIG. 7 is a cross-sectional view taken along line C-C of FIG. 4;

FIG. 8 is a cross-sectional view taken along line D-D of FIG. 4;

in the figure: 1-multi-shaft device, 2-motor with reducer, 3-universal joint, 4-equal dividing straight-groove slideway plate, 5-equal dividing expansion plate, 6-lower equal dividing straight-groove slideway plate, 7-guide ring, 8-rotating shaft, 9-thrust ball bearing, 10-upper straight-groove guide sleeve, 11-arc guide sleeve, 12-needle bearing, 13-lower straight-groove guide sleeve, 14-locking cylinder, 15-locking bar, 16-control system, 17-control cable, 18-upper straight groove, 19-arc groove, 20-lower straight groove, 21-locking block, 22-disc spring and 23-locking retainer ring.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings of the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention. Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", and the like, indicate orientations and positional relationships based on those shown in the drawings, and are used only for convenience of description and simplicity of description, and do not indicate or imply that the equipment or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be considered as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

In the description of the present invention, it should be noted that the terms "upper", "lower", "left", "right", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention.

Example one

Referring to fig. 1-8, the present invention provides a technical solution, a multi-axis adjuster for automatically adjusting equal-divided axial distance, comprising a multi-axis device 1, an equal-divided straight-grooved slideway plate 4 and an equal-divided expansion plate 5, which are coaxially arranged from top to bottom, wherein the multi-axis device 1 is fixedly connected with the equal-divided straight-grooved slideway plate 4, a plurality of axes equidistantly arranged along the circumferential direction are arranged on the lower end surface of the multi-axis device 1, each axis is connected with a rotating shaft 8 through a universal joint 3, a guide ring 7 is fixed on the lower end surface of the equal-divided straight-grooved slideway plate 4, wherein the equal-divided expansion plate 5 is rotatably arranged in the guide ring 7, a motor 2 with a speed reducer for driving the equal-divided expansion plate 5 to rotate is fixed at the center of the upper end surface of the equal-divided straight-grooved slideway plate 4, a plurality of upper straight grooves 18 corresponding to the rotating shafts 8 are arranged on the equal-divided straight-grooved slideway plate 4, the upper straight groove 18 extends along the radial direction, the equal division expansion plate 5 is provided with a plurality of arc-shaped grooves 19 which correspond to the positions of the rotating shaft 8 one by one, the arc-shaped grooves 19 are arranged at equal intervals along the circumferential direction, the rotating shaft 8 sequentially penetrates through the upper straight groove 18 and the arc-shaped grooves 19, and the rotating shaft 8 can move along the upper straight groove 18 and the arc-shaped grooves 19.

In this embodiment, the motor 2 with a speed reducer is a stepping motor with a speed reducer or a servo motor with a speed reducer.

In the present embodiment, the motor 2 with a speed reducer is connected to a control system 16 through a control cable 17.

In the embodiment, the output shaft of the motor 2 with the speed reducer can be connected with the equal-division expansion plate 5 through gear transmission or synchronous belt transmission.

In this embodiment, two locking cylinders 14 symmetrically arranged on two sides of the guide ring 7 are fixed on the lower end surface of the equally-divided straight-groove slideway 4, a locking strip 15 is arranged below the guide ring 7, two ends of the locking strip 15 are respectively connected with output ends of the two locking cylinders 14, and two locking blocks 21 are arranged on one side of the locking strip 15 facing the equally-divided unfolding plate 5.

In this embodiment, a lower bisection straight-groove slideway plate 6 is arranged below the bisection expansion plate 5 in the guide ring 7, wherein the lower bisection straight-groove slideway plate 6 can move up and down in the guide ring 7, the lower bisection straight-groove slideway plate 6 is connected with two locking blocks 21, the lower bisection straight-groove slideway plate 6 is provided with a plurality of lower straight grooves 20 corresponding to the positions of the rotating shafts 8 one by one, wherein the lower straight grooves 20 extend in the radial direction, and the rotating shafts 8 penetrate through the lower straight grooves 20 and can move along the lower straight grooves 20.

In this embodiment, the rotating shaft 8 is provided with a needle bearing 12, and an upper straight groove guide sleeve 10 capable of moving along an upper straight groove 18, an arc-shaped guide sleeve 11 capable of moving along an arc-shaped groove 19, and a lower straight groove guide sleeve 13 capable of moving along a lower straight groove 20 are sleeved outside the needle bearing 12.

In this embodiment, thrust ball bearings 9 are disposed on the rotating shaft 8 at the upper and lower ends of the needle bearing 12, and a disc spring 22 and a locking collar 23 are sequentially disposed on the upper end of the rotating shaft 8 above the needle bearing 12 from bottom to top.

In the present embodiment, the arc-shaped slot 19 is a slant line or a curve.

In this embodiment, the curve is an arc line or an involute.

The using method comprises the following steps: during adjustment, an adjusting position is set through the control system 16, after a size to be adjusted is set, the halving expansion plate 5 is driven to rotate through the motor 2 with the speed reducer, so that the arc-shaped guide sleeve 11 is driven to move in the arc-shaped groove 19, the arc-shaped guide sleeve 11 is connected to the upper straight groove guide sleeve 10 and the lower straight groove guide sleeve 13 through the needle bearing 12 due to the connected rotating shaft 8, so that the rotating shaft 8 is limited to rotate, the rotating shaft 8 only can slide along the arc-shaped groove 19, and the plurality of rotating shafts 8 are driven to move inwards or outwards along the direction of the upper straight groove 18 of the halving straight groove slideway plate 4, so that the axial distance of the rotating shaft 8 is quickly adjusted and accurately positioned, after adjustment, the locking strip 15, the locking block 21 and the lower halving expansion plate 6 are driven to move towards one side of the halving expansion plate 5 through the locking cylinder 14, and the lower halving straight groove slideway plate 6 clamps the halving expansion plate 5, so that the halving expansion plate 5 cannot rotate, the position of the rotating shaft 8 is prevented from changing during processing, and the equant rotating shafts 8 are quickly and accurately positioned through the actions.

The disc spring 22 may be replaced with another spring. The rotating shaft 8 can be processed into various structures according to the requirements, and the head of the rotating shaft 8 can also be processed into various joints according to the requirements.

Example two

Referring to fig. 1-8, the present invention provides a technical solution, a multi-axis adjuster for automatically adjusting equal-divided axial distance, comprising a multi-axis device 1, an equal-divided straight-grooved slideway plate 4 and an equal-divided expansion plate 5, which are coaxially arranged from top to bottom, wherein the multi-axis device 1 is fixedly connected with the equal-divided straight-grooved slideway plate 4, a plurality of axes equidistantly arranged along the circumferential direction are arranged on the lower end surface of the multi-axis device 1, each axis is connected with a rotating shaft 8 through a universal joint 3, a guide ring 7 is fixed on the lower end surface of the equal-divided straight-grooved slideway plate 4, wherein the equal-divided expansion plate 5 is rotatably arranged in the guide ring 7, a motor 2 with a speed reducer for driving the equal-divided expansion plate 5 to rotate is fixed at the center of the upper end surface of the equal-divided straight-grooved slideway plate 4, a plurality of upper straight grooves 18 corresponding to the rotating shafts 8 are arranged on the equal-divided straight-grooved slideway plate 4, the upper straight groove 18 extends along the radial direction, the equal division expansion plate 5 is provided with a plurality of arc-shaped grooves 19 which correspond to the positions of the rotating shaft 8 one by one, the arc-shaped grooves 19 are arranged at equal intervals along the circumferential direction, the rotating shaft 8 sequentially penetrates through the upper straight groove 18 and the arc-shaped grooves 19, and the rotating shaft 8 can move along the upper straight groove 18 and the arc-shaped grooves 19.

In this embodiment, the motor 2 with a speed reducer is a stepping motor with a speed reducer or a servo motor with a speed reducer.

In the present embodiment, the motor 2 with a speed reducer is connected to a control system 16 through a control cable 17.

In the embodiment, the output shaft of the motor 2 with the speed reducer can be connected with the equal-division expansion plate 5 through gear transmission or synchronous belt transmission.

In this embodiment, two locking cylinders 14 symmetrically arranged on two sides of the guide ring 7 are fixed on the lower end surface of the bisector chute plate 4, a locking strip 15 is arranged below the guide ring 7, two ends of the locking strip 15 are respectively connected with output ends of the two locking cylinders 14, and two locking blocks 21 are arranged on one side of the locking strip 15 facing the bisector chute plate.

In this embodiment, the rotating shaft 8 is provided with a needle bearing 12, and an upper straight groove guide sleeve 10 capable of moving along an upper straight groove 18 and an arc-shaped guide sleeve 11 capable of moving along an arc-shaped groove 19 are sleeved outside the needle bearing 12.

In this embodiment, thrust ball bearings 9 are disposed on the rotating shaft 8 at the upper and lower ends of the needle bearing 12, and a disc spring 22 and a locking collar 23 are sequentially disposed on the upper end of the rotating shaft 8 above the needle bearing 12 from bottom to top.

In the present embodiment, the arc-shaped slot 19 is a slant line or a curve.

In this embodiment, the curve is an arc line or an involute.

The using method comprises the following steps: during adjustment, an adjusting position is set through the control system 16, after a size to be adjusted is set, the halving expansion plate 5 is driven to rotate through the motor 2 with the speed reducer, so that the arc-shaped guide sleeve 11 is driven to move in the arc-shaped groove 19, the arc-shaped guide sleeve 11 is connected to the upper straight groove guide sleeve 10 through the needle bearing 12 due to the connected rotating shaft 8 to limit the rotating shaft 8 to rotate, the rotating shaft 8 only can slide along the arc-shaped groove 19, so that the plurality of rotating shafts 8 are driven to move inwards or outwards along the direction of the upper straight groove 18 of the halving straight groove slideway plate 4, so that the quick adjustment and the accurate positioning of the shaft distance of the rotating shafts 8 are realized, after adjustment, the locking air cylinder 14 drives the locking strips 15 and the locking blocks 21 to move towards one side of the halving expansion plate 5, and the locking blocks 21 clamp the halving expansion plate 5, so that the halving expansion plate 5 cannot rotate, the position of the rotating shafts 8 is prevented from changing during processing, and through the actions, and the quick and accurate positioning of each equal-division rotating shaft 8 is realized.

The disc spring 22 may be replaced with another spring. The rotating shaft 8 can be processed into various structures according to the requirements, and the head of the rotating shaft 8 can also be processed into various joints according to the requirements.

The positioning device is reasonable in design, simple in structure, convenient to operate, time-saving, efficient, high in use flexibility and practicability and has popularization value, and the equal split shafts are quickly and accurately positioned.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein, and any reference signs in the claims are not intended to be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.