CN102767716B - Wiring groove and installation part integrated module lamp - Google Patents

Abstract

The invention discloses a wiring duct and mounting piece integrated module lamp, which is provided with a wiring duct mounting rack, wherein at least one LED light-emitting module is connected to the wiring duct mounting rack through a fixing piece; the inside wiring groove that link up from one end toward the other end that is equipped with of wire casing mounting bracket, just wire casing mounting bracket lateral wall is equipped with the outlet that link up between wiring groove and the wire casing mounting bracket outside. The LED light-emitting module has the advantages of being fast in installation, easy to maintain, simple in structure, low in cost and easy to popularize, improving product quality, improving construction efficiency, strengthening firmness, improving attractiveness, freely adjusting the distance between the LED light-emitting modules, being capable of adjusting the angle of the LED light-emitting modules by 360 degrees, reducing the service life of a product due to the action of gravity by using an external power supply, being good in heat dissipation effect, reducing light attenuation, improving lighting effect, prolonging the service life of the product, and achieving the effect of simple structure and low cost.

Description

A modular lamp integrated with wiring trough and mounting parts

technical field

The invention relates to the technical field of lamps, in particular to a modular lamp integrated with a wiring trough and a mounting part.

Background technique

Due to the advantages of long service life, short start-up time, remarkable energy-saving effect, no ultraviolet radiation and environmental pollution, and high safety performance, LED lighting products have been widely recognized and have become the mainstream of energy-saving lamps in the future.

Users have various requirements for lamps, including indoor and outdoor use, no product damage due to changes in the external environment, and high product safety requirements (such as not being blown by strong winds to cause the product to fall off, No short circuit of the product due to rain), can self-adjust the density between the LED light-emitting modules to achieve different light effects, and can adjust the angle of the LED light-emitting modules.

Traditional LED lighting fixtures are equipped with a small mounting frame for one LED light-emitting module. When more LED light-emitting modules need to be installed on a large wall, the constructor needs to install many LED lighting fixtures. The construction is difficult and labor-intensive. Low work efficiency, difficult maintenance, can not freely adjust the distance between the LED light-emitting modules after construction, can not adjust the light-emitting angle of the LED light-emitting modules, wiring is difficult, complex wiring affects the appearance, and the wires are easily damaged by the external environment destroy.

Contents of the invention

The purpose of the present invention is to address the shortcomings of the above problems, to provide a modular lamp integrated with wiring trough and mounting parts, which has the advantages of quick installation, easy maintenance, improved product quality, improved construction efficiency, enhanced firmness, and improved aesthetics. Freely adjust the distance between the LED light-emitting modules, can adjust the angle of the LED light-emitting modules 360 degrees, use an external power supply to reduce the product's service life due to gravity, good heat dissipation, reduce light decay, and improve light efficiency , prolong the service life of the product, the advantages of simple structure, low cost and easy promotion.

In order to achieve the above object, the present invention adopts the following technical solutions:

An integrated modular lamp with a wiring trough and a mounting part, which is provided with a wiring trough mounting frame, and at least one LED light-emitting module is fixedly connected to the wire trough mounting frame through a fixing part; The wire trough penetrates to the other end, and the side wall of the wire trough installation frame is provided with an outlet opening between the wire trough and the outside of the wire trough installation frame.

The cross-section of the trunking installation frame is circular, or square, or semicircular; the outlet of the trunking installation frame is a gap that runs through from one end to the other end, or is formed by a number of wire slots arranged at intervals. The small hole on the mounting bracket is formed; the small hole is in the shape of a hole, or in the shape of a through hole.

The fixing part is composed of a number of screws, or a perforated structure arranged on the side wall of the trunking mounting frame, and a rotary lock provided on the lamp body and locked with the perforated structure, or formed on the side wall of the lamp body and It is composed of an open arc-shaped ring that matches the curve of the trunking mounting frame and a locking screw; wherein both ends of the open arc-shaped ring are provided with threaded holes; one end of the locking screw is connected with a threaded hole Screw structure, the other end is a handle. By rotating the handle, the distance between the two threaded holes can be adjusted through the thread structure, so as to increase the frictional force between the wire groove installation frame and the LED lighting module.

The fixed part is installed on the lamp body by screws, the fastener one is hinged with the fastener one and cooperates with the fastener one to form a small hole for installation, the fastener handle is hinged with the movable fastener through the lock pin, and one end is connected with the fastener. The handle of the fastener is hinged and the other end buckles the C buckle of fastener one.

The LED light-emitting module is provided with a tray installed on the wire slot mounting frame, a lamp body arranged above the tray, a PCB substrate closely attached to the upper end of the lamp body, and several LED light-emitting chips evenly arranged on the PVB substrate. The lens above the LED light-emitting chip, the cover above the lens, the plug electrically connected to the LED light-emitting chip, the first mounting part and the second mounting part; the cover is fixedly connected to the lamp body through screws; The tray is fixedly connected to the lamp body through screws; the upper end of the lamp body is a plane heat conduction part that cooperates with the heat conduction of the PCB substrate, the middle of the lower end is a fin heat dissipation part, and the left side of the lower end is the first hinged hole formed by the first mounting part. The sliding guide groove, the right side of the lower end is a second sliding guide groove that cooperates with the second mounting piece to form a second reaming hole.

A second trunking installation frame is installed in the second sliding guide groove.

In order to securely install the present invention on the wall or ceiling, the present invention also includes: a first mounting seat and a second mounting seat; one end of the first mounting seat is fixed on the wall by screws, and the other end is connected to the wire The left end of the slot mounting frame is fixedly connected; one end of the second mounting base is fixedly mounted on the wall by screws, and the other end is fixedly connected with the right end of the wire slot mounting frame.

Further, the first mounting seat is socketed with the left end of the trunking mounting frame, and is locked and limited by screws. The second mounting seat is socketed with the right end of the trunking mounting frame, and is locked and limited by screws.

In order to make the present invention firmly installed on the wall or ceiling, etc., it also includes: a third mounting base and a fourth mounting base; one end of the third mounting base is fixed on the wall by screws, and the other end is installed with the second wire slot The left end of the frame is fixedly connected; one end of the fourth mounting seat is fixedly mounted on the wall by screws, and the other end is fixedly connected with the right end of the second trunking mounting frame.

Further, the third installation base is socketed with the left end of the second trunking installation frame, and locked and limited by screws. The fourth installation base is socketed with the right end of the second trunking installation frame, and is locked and limited by screws.

In order to make the present invention have more installation methods, the present invention also includes: a chain, one end of which is fixed on the ceiling, and the other end is fixed on the wire groove installation frame. The trunking installation frame with a shorter specification is generally hung by two chains, while the trunking installation frame with a longer specification can be hung by several chains.

For a better heat dissipation effect, a heat dissipation layer made of heat dissipation material is coated between the PCB substrate and the planar heat conduction portion of the lamp body.

The wire trough installation frame is a wire trough installation frame with a round tube shape and a number of wire outlets evenly spaced on the side wall, or a wire trough installation frame with an arc-shaped cross section; the second wire trough installation frame is a The second trunking mounting frame is in the shape of a round tube and the side walls are evenly spaced with several wire outlets, or the second trunking mounting frame is arc-shaped in cross section.

In order to ensure that the present invention is not affected by rain in harsh environments such as outdoors, the side wall of the PCB substrate is provided with a silicone ring for waterproofing.

Further, the first mounting part is fixedly connected to the lower end of the lamp body through bolts; the second mounting part is fixedly connected to the lower end of the lamp body through bolts.

Further, the tray is fixedly connected to the side wall of the lamp body through bolts.

The lens is an integrally formed optical lens.

The first mounting part and the second mounting part are closely attached to the lamp body, which is conducive to the dissipation of heat in the LED lighting module and improves the heat dissipation effect.

Further, the lamp body is manufactured in an integrated manner.

Further, the cover is an aluminum alloy cover.

Further, the lamp body is an aluminum alloy lamp body.

Further, the aluminum alloy cover and the aluminum alloy lamp body are fixedly connected by four screws; the four corners of the aluminum alloy cover are respectively provided with screw holes; the plane heat conduction part at the upper end of the aluminum alloy lamp body There are four threaded holes corresponding to the screw holes of the aluminum alloy cover.

Further, the optical lens is provided with a bottom plate, and the bottom plate is provided with a plurality of installation holes for LED light-emitting chips. The top of the bottom plate corresponding to the installation holes is provided with a condensing lens, and the bottom of the bottom plate is provided with an uneven frosted surface; The bottom plate, condenser lens, and frosted surface are integrally formed.

The first mode of use is: only use the way of installing the rack for a single trunking. Firstly, the trunking installation frame is fixedly installed on the wall through the first mounting seat and the second mounting seat, and then the trunking mounting frame is fixedly connected between the first mounting seat and the second mounting seat, and then the external The wires of the power supply are laid in the wiring trough, and then several LED light emitting modules are installed on the wire trough mounting bracket, and the plugs of the LED light emitting modules and the connectors of the external power supply are installed correspondingly, and the LED lighting can be adjusted by adjusting the locking screw The lighting angle of the module and the distance between the LED lighting module and the LED lighting module are used to adjust the intensity of light in different places.

The second usage mode is: adopt the chain mode. First, install the trunking mounting frame on the wall through the first mounting seat and the second mounting seat through screws, fix the trunking mounting frame between the first mounting seat and the second mounting seat, and then install the outer Lay the wires for the power supply in the wiring trough, then install the second wiring trough mounting frame on the wall through the third mounting base and the fourth mounting base with screws, and then install several LED light-emitting modules on the wire trough mounting frame and the second wire slot mounting frame, install the plug of the LED lighting module and the connector of the external power supply correspondingly, and adjust the lighting angle of the LED lighting module and the distance between the LED lighting module and the LED lighting module by adjusting the locking screw. distance to adjust the intensity of light in different places.

The third mode of use is: the way of using the wire slot installation frame and the second wire slot installation frame at the same time. First, fix the trunking mounting frame and the second trunking mounting frame on the wall through the first mounting seat, the second mounting seat, the third mounting seat and the fourth mounting seat, and then lay the wires of the external power supply on the wiring Then install several LED light-emitting modules on the line slot installation frame and the second line slot installation frame, and install the plugs of the LED light-emitting modules and the connectors of the external power supply correspondingly. The LED light-emitting modules can be debugged by adjusting the locking screw. The lighting angle of the group and the distance between the LED lighting module and the LED lighting module can adjust the intensity of light in different places. Simultaneous use of the wire slot installation frame and the second wire slot installation frame is beneficial to reduce the influence of the product weight on the service life, improve the firmness and improve the heat dissipation effect.

The trunking installation frame of the present invention integrates the functions of installing LED light-emitting modules and wiring. The outside of the wiring trough mounting frame is used for fixedly installing several LED lighting modules, the inner wiring trough is used for wiring, and the wire outlet is for the wires to pass through the wiring trough.

The present invention adopts the above structure, has quick installation, easy maintenance, improves product quality, improves construction efficiency, strengthens firmness, improves aesthetics, freely adjusts the distance between LED light-emitting modules, and can adjust the angle of LED light-emitting modules 360 degrees , Using an external power supply to reduce the shortened product life due to gravity, good heat dissipation, reduce light decay, improve light efficiency, prolong product life, simple structure, low cost, and easy to promote.

Description of drawings

Fig. 1 is an exploded schematic diagram of the third use mode of the present invention.

Fig. 2 is a schematic top view of the third usage mode of the present invention.

Fig. 3 is a schematic front view of the third usage mode of the present invention.

FIG. 4 is a perspective view of a third usage mode of the present invention.

Fig. 5 is a schematic diagram of the third usage mode of the present invention.

Fig. 6 is a schematic diagram of the first usage mode of the present invention.

Fig. 7 is a schematic diagram of the third usage mode of the present invention.

Fig. 8 is a schematic diagram of the first usage mode of the present invention.

Fig. 9 is a schematic diagram of the first usage mode of the present invention.

Fig. 10 is a schematic diagram of the first usage mode of the present invention.

Fig. 11 is a schematic diagram of the first usage mode of the present invention.

Fig. 12 is a schematic diagram of the third usage mode of the present invention.

Fig. 13 is a schematic diagram of the third usage mode of the present invention.

Fig. 14 is a schematic diagram of the trunking installation frame of the present invention.

Fig. 15 is a schematic diagram of the trunking installation frame of the present invention.

Fig. 16 is a schematic diagram of assembly of the fixing element of the present invention.

Fig. 17 is an exploded schematic view of the fixing member of the present invention.

The present invention will be further described below by means of drawings and specific embodiments.

Detailed ways

As shown in Figures 1 to 17, the present invention is a modular lamp integrated with wire trough and mounting parts, which is provided with a wire trough mounting frame 13, and at least one LED light-emitting module is fixedly connected to the wire trough mounting frame 13 through a fixing piece. group; the inside of the wire trough mounting frame 13 is provided with a wire trough 131 penetrating from one end to the other end, and the side wall of the wire trough mounting frame 13 is provided with a connection between the wire trough 131 and the outside of the wire trough mounting frame Outlet 132.

The fixing part is composed of a number of screws, or a perforated structure arranged on the side wall of the trunking mounting frame, and a rotary lock provided on the lamp body and locked with the perforated structure, or formed on the side wall of the lamp body and It is composed of an open arc-shaped ring that matches the curve of the trunking mounting frame and a locking screw; wherein both ends of the open arc-shaped ring are provided with threaded holes; one end of the locking screw is connected with a threaded hole Screw structure, the other end is a handle. By rotating the handle, the distance between the two threaded holes can be adjusted through the thread structure, so as to increase the frictional force between the wire groove installation frame and the LED lighting module. 

The fixing part is installed on the lamp body by screws, the fastener one 111, the movable fastener 112 that is hinged with the fastener one and cooperates with the fastener one to form a small hole for installation, and the fastener handle that is hinged with the movable fastener through the lock pin 115 114, one end is hinged with the fastener handle and the other end buckles the C buckle 113 of fastener one.

The LED light-emitting module is provided with a tray 11 installed on the wire slot mounting frame 13, a lamp body 12 arranged above the tray 11, a PCB substrate 4 closely attached to the upper end of the lamp body 12, and several evenly arranged on the PVB substrate 4, the LED light-emitting chip 5 on the LED light-emitting chip 5, the lens 2 above the LED light-emitting chip 5, the cover 1 above the lens 2, the plug 7 electrically connected to the LED light-emitting chip 5, the first mounting part 14 and the second mounting 10; the cover 1 is fixedly connected to the lamp body 12 by screws; the tray 11 is fixedly connected to the lamp body 12 by screws; It is the fin cooling part 123, the left side of the lower end is the first sliding guide groove 122 that cooperates with the first mounting part 14 to form the first hinged hole, and the right side of the lower end is the second sliding guide groove 122 that cooperates with the second mounting part 10 to form the second hinged hole. Slot 124.

The second wire groove installation frame 8 is installed in the second sliding guide groove 124 .

The cross-section of the trunking mounting frame is circular, or square, or semicircular; the outlet of the trunking mounting frame is a gap that runs from one end to the other end, or is formed by several wire slots arranged at intervals. The small hole on the mounting bracket is formed; the small hole is in the shape of a hole, or in the shape of a through hole.

In order to securely install the present invention on the wall 300 or the ceiling, the present invention also includes: a first mounting base 100 and a second mounting base 200; one end of the first mounting base 100 is fixed on the wall 300 by screws , the other end is fixedly connected to the left end of the trunking mounting frame 13; one end of the second mounting base 200 is fixedly installed on the wall 300 by screws, and the other end is fixedly connected to the right end of the trunking mounting frame 13.

Further, the first mounting seat 100 is socketed with the left end of the trunking mounting frame 13, and locked and limited by screws. The second mounting base 200 is socketed with the right end of the trunking mounting bracket 13, and is locked and limited by screws.

In order to make the present invention firmly installed on the wall 300 or the ceiling, etc., it also includes: a third mounting base 400 and a fourth mounting base 500; one end of the third mounting base 400 is fixed on the wall 300 by screws, and the other end It is fixedly connected with the left end of the second trunking mounting frame 8 ; one end of the fourth mounting base 500 is fixedly mounted on the wall 300 by screws, and the other end is fixedly connected with the right end of the second trunking mounting frame 8 .

Further, the third installation base 400 is socketed with the left end of the second trunking installation frame 8, and locked and limited by screws. The fourth installation base 500 is socketed with the right end of the second trunking installation frame 8, and locked and limited by screws.

In order to make the present invention have more installation methods, the present invention also includes: a chain, one end of which is fixed on the ceiling, and the other end is fixed on the wire groove installation frame 13. The wire duct installation frame 13 with shorter specifications generally adopts two chains to hang, while the wire duct installation rack with longer specifications can adopt several chains to hang.

For a better heat dissipation effect, a heat dissipation layer made of heat dissipation material is coated between the PCB substrate 4 and the planar heat conduction portion 121 of the lamp body 12 .

The wire groove installation frame 13 is a wire groove installation frame 13 that is a round tube and has several outlets evenly spaced on the side wall, or a wire groove installation frame 13 that is arc-shaped in cross section; the second wire groove installation The frame 8 is a second trunking installation frame 8 in the shape of a round tube with several wire outlets evenly spaced on the side wall, or a second trunking installation frame 8 with an arc-shaped cross section.

In order to ensure that the present invention is not affected by rain in harsh environments such as outdoors, the side wall of the PCB substrate is provided with a silicone ring 3 for waterproofing.

Further, the first mounting part 14 is fixedly connected to the lower end of the lamp body 12 through bolts; the second mounting part 10 is fixedly connected to the lower end of the lamp body 12 through bolts.

Further, the tray 11 is fixedly connected to the side wall of the lamp body 12 through bolts.

The lens 2 is an integrally formed optical lens.

The first mounting part 14 and the second mounting part 10 are closely attached to the lamp body 12, which is conducive to the dissipation of heat in the LED light emitting module and improves the heat dissipation effect.

Further, the lamp body 12 is manufactured in an integral molding manner.

Further, the cover 1 is an aluminum alloy cover.

Further, the lamp body 12 is an aluminum alloy lamp body.

Further, the aluminum alloy cover 1 and the aluminum alloy lamp body 12 are fixedly connected by four screws; the four corners of the aluminum alloy cover 1 are respectively provided with screw holes; the upper end of the aluminum alloy lamp body 12 is There are four threaded holes in the corresponding positions of the plane heat conduction part and the screw holes of the aluminum alloy cover.

Further, the optical lens 2 is provided with a bottom plate, and the bottom plate is provided with a plurality of mounting holes for LED light-emitting chips, a condenser lens is provided above the bottom plate corresponding to the mounting holes, and an uneven frosted surface is provided below the bottom plate; The bottom plate, the condenser lens and the frosted surface are integrally formed.

The first mode of use is: the mode of only using a single trunking installation frame 13 . First, the trunking installation frame 13 is fixedly installed on the wall 300 through the first mounting seat 100 and the second mounting seat 200, and then the trunking mounting frame 13 is fixedly connected to the first mounting seat 100 and the second mounting seat 200. In between, lay the wires of the external power supply in the wiring trough 131, then install several LED light emitting modules on the wire trough mounting frame 13, and install the plugs of the LED light emitting modules and the connectors of the external power supply correspondingly. , By adjusting the locking screw, the lighting angle of the LED lighting module and the distance between the LED lighting module and the LED lighting module can be adjusted to adjust the intensity of light in different places.

The second usage mode is: adopt the chain mode. First, the trunking installation frame 13 is fixed and installed on the wall 300 through the first mounting seat 100 and the second mounting seat 200 by screws, and the trunking mounting frame 13 is fixedly connected to the first mounting seat 100 and the second mounting seat 200, then the wires of the external power supply are laid in the wire slot 131, and then the second wire slot mounting frame 8 is fixed on the wall 300 through the third mounting base 400 and the fourth mounting base 500 by screws, and then Install several LED light-emitting modules on the wire slot installation frame 13 and the second wire slot installation frame 8, and install the plugs of the LED light-emitting modules and the connectors of the external power supply correspondingly, and adjust the locking screw of the LED light-emitting modules. The lighting angle and the distance between the LED lighting module and the LED lighting module can adjust the intensity of light in different places.

The third usage mode is: the way of using the trunking mounting frame 13 and the second trunking mounting frame 8 at the same time. First, the trunking mounting frame 13 and the second trunking mounting frame 8 are fixedly installed on the wall 300 through the first mounting seat 100, the second mounting seat 200, the third mounting seat 400 and the fourth mounting seat 500, and then the external The wires of the power supply are laid in the wiring trough 131, and then several LED light emitting modules are installed on the wire trough mounting frame 13 and the second wire trough mounting frame 8, and the plugs of the LED light emitting modules and the connectors of the external power supply are installed correspondingly , By adjusting the locking screw, the lighting angle of the LED lighting module and the distance between the LED lighting module and the LED lighting module can be adjusted to adjust the intensity of light in different places. Simultaneous use of the wire slot installation frame and the second wire slot installation frame is beneficial to reduce the influence of the product weight on the service life, improve the firmness and improve the heat dissipation effect.

The present invention adopts the above structure, has quick installation, easy maintenance, improves product quality, improves construction efficiency, strengthens firmness, improves aesthetics, freely adjusts the distance between LED light-emitting modules, and can adjust the angle of LED light-emitting modules 360 degrees , Using an external power supply to reduce the shortened product life due to gravity, good heat dissipation, reduce light decay, improve light efficiency, prolong product life, simple structure, low cost, and easy to promote.

The above description does not limit the technical solutions of the present invention, and any technology that does not deviate from the spirit of the present invention falls within the scope of the claims of the present invention.

Claims (7)

1. a trough and the integrated module lamp of installed part, it is characterized in that: be provided with chain and wire casing installing rack, on described wire casing installing rack, by fixture, be fixedly connected with at least one LED illuminating module, and chain one end is fixed on and day takes, the other end is fixed on wire casing installing rack; And described wire casing installing rack inside is provided with the trough connecting toward the other end from one end, and described wire casing installing rack sidewall is provided with the line outlet connecting between trough and wire casing installing rack outside; Described fixture is by be arranged on lamp body upper fastener one by screw, hinged and fasteners one forms the moving fastening that aperture is installed with fastener one, by lock pin and the hinged fastener handle of moving fastening, the C button that the hinged and other end of one end and fastener handle fastens fastener one forms.

2. according to a kind of trough described in claim 1 and the integrated module lamp of installed part, it is characterized in that: the cross section of described wire casing installing rack is rounded, or is square, or semicircular in shape; The line outlet of described wire casing installing rack is the breach that one end connects toward the other end, or several apertures that are spaced on wire casing installing rack of serving as reasons form; Described aperture is hole shape, or is through hole shape first.

3. according to a kind of trough described in claim 1 and the integrated module lamp of installed part, it is characterized in that: described LED illuminating module is provided with the pallet being arranged on wire casing installing rack, be located at the lamp body of pallet top, fit tightly the substrate at the PCB of lamp body upper end, several are evenly arranged in the LED luminescence chip on PCB substrate, are located at the lens of LED luminescence chip top, are located at the cover of lens top, with the plug that LED luminescence chip is electrically connected, the first installed part and the second installed part; Described cover is fixedly connected with lamp body by screw; Described pallet is fixedly connected with lamp body by screw; Described lamp body upper end is for coordinating the plane heat-conducting part of PCB substrate heat conduction, in the middle of lower end, it is fin radiating part, left side, lower end is for coordinating the first installed part to form the first sliding guide groove of the first fraising, and right side, lower end is for coordinating the second installed part to form the second sliding guide groove of the second fraising.

4. according to a kind of trough described in claim 3 and the integrated module lamp of installed part, it is characterized in that: the second wire casing installing rack is installed in described the second sliding guide groove.

5. according to a kind of trough described in claim 1 and the integrated module lamp of installed part, characterized by further comprising: the first mount pad and the second mount pad; Described first mount pad one end is fixedly mounted on body of wall by screw, and the other end is fixedly connected with wire casing installing rack left end; Described second mount pad one end is fixedly mounted on body of wall by screw, and the other end is fixedly connected with wire casing installing rack right-hand member.

6. according to a kind of trough described in claim 4 and the integrated module lamp of installed part, characterized by further comprising: the 3rd mount pad and the 4th mount pad; Described the 3rd mount pad one end is fixedly mounted on body of wall by screw, and the other end is fixedly connected with the second wire casing installing rack left end; Described the 4th mount pad one end is fixedly mounted on body of wall by screw, and the other end is fixedly connected with the second wire casing installing rack right-hand member.

7. according to a kind of trough described in claim 4 and the integrated module lamp of installed part, it is characterized in that: described wire casing installing rack is the cylindrical and sidewall wire casing installing rack of several line outlets that is evenly intervally arranged, or is the curved wire casing installing rack of cross section; Described the second wire casing installing rack is a cylindrical and sidewall the second wire casing installing rack of several line outlets that is evenly intervally arranged, or is the second curved wire casing installing rack of cross section.