Intelligent wiredrawing, twisting and winding machine
By introducing a guide unit into the intelligent wire drawing and winding machine, the orderly batch guidance of the wires is achieved, which solves the problem of wire entanglement, improves production stability and efficiency, and simplifies the equipment structure.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SHANDONG YOUHAO INTELLIGENT EQUIPMENT CO LTD
- Filing Date
- 2025-06-27
- Publication Date
- 2026-05-15
AI Technical Summary
In existing intelligent wire drawing and winding devices, the wire routing layout is unreasonable, which easily leads to tangling, resulting in complex equipment structure, high labor intensity for workers, and low production efficiency.
A guide unit extending along the Y direction at the top of the frame is adopted, including a first row of guide frames, a second row of guide frames, a third row of guide frames, and a fourth row of guide frames. By precisely controlling the number and arrangement of guide hooks, the orderly batch guidance of the yarn is achieved, avoiding tangling.
It effectively avoids thread tangling, improves the stability and continuity of production, simplifies the equipment structure, reduces the labor intensity of workers, and improves production efficiency.
Smart Images
Figure CN224242425U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of winding machine equipment technology, and in particular to an intelligent wire drawing, twisting and winding machine. Background Technology
[0002] In the field of wire drawing production, the winding device, as the last step in the wire drawing process, plays an important role in winding the drawn monofilaments onto an I-beam or straight tube. The monofilaments wound by the device are key raw materials for subsequent processes such as rope making, wire bonding, and web weaving. Although they are semi-finished products, they occupy an important position in the entire industrial chain.
[0003] In existing technologies, intelligent wire drawing and winding devices mainly consist of a winding device body, a wire winding plate frame, a single-filament positioning bracket, and a power drive system. The winding device body, wire winding plate frame, and single-filament positioning bracket are arranged sequentially, with the wire winding plate frame and the winding device body achieving relative positional movement through a sliding connection. Specifically, tracks or sliding components are installed on the wire winding plate frame and the winding device body, respectively. Positional changes are achieved by the sliding components sliding on the tracks. The sliding components can be installed on the wire winding plate frame or the winding device body; components without sliding components require a compatible track. The sliding components are connected to a motor, a power device. The rotation of the motor drives the sliding components to rotate, achieving reciprocating motion using the forward and reverse rotation principle of the motor. Limit switches are added to the forward and backward limit sections, or the displacement of the sliding device is precisely controlled using programs based on the displacement per revolution of the motor, thereby achieving automated control of the reciprocating motion of the wire winding plate frame. While this device can simultaneously twist monofilaments during the winding process, reducing subsequent twisting steps, significantly shortening production time, and greatly improving the production efficiency of CNC automatic twisting machines, increasing production demands often necessitates the arrangement of multiple winding drive components per machine to further enhance efficiency. For example, assuming a common arrangement of 36 winding drive components in a 3x12 rectangular matrix, with the yarns laid out horizontally, this requires three horizontal rows of yarns. The numerous yarns involved in the winding process not only complicate the equipment structure but also easily lead to tangling. Once tangling occurs, workers must manually untangle each yarn, undoubtedly increasing their workload, reducing production efficiency, and affecting the stability and reliability of the equipment. This has become a bottleneck for the further development and application of this technology, urgently requiring optimization and improvement.
[0004] Therefore, there is an urgent need for an intelligent wire drawing and winding device that can optimize the wire routing layout, effectively avoid wire tangling, simplify the equipment structure, reduce the labor intensity of workers, and at the same time ensure the efficient and stable operation of multiple winding drive components, so as to meet the growing demand of modern industrial production for wire drawing and winding processes. Utility Model Content
[0005] The purpose of this application is to provide an intelligent wire drawing, twisting and winding machine to solve the problems of unreasonable wire routing and general reliability in the existing technology.
[0006] The embodiments of this application can be implemented through the following technical solutions:
[0007] An intelligent wire drawing, twisting and winding machine includes a winding drum, a winding transmission assembly, a steel collar, and a monofilament positioning assembly integrated on a frame;
[0008] It also includes a guide unit located on top of the frame and extending along the Y direction;
[0009] The guiding unit includes a first row of guide frames, a second row of guide frames, a third row of guide frames, and a fourth row of guide frames. The third row of guide frames and the fourth row of guide frames are arranged at intervals and are respectively located on both sides of the second row of guide frames. Each guide frame is provided with a guide hook, and a number of the guide hooks located on the first row of guide frames and the second row of guide frames are arranged sequentially along the length of the guide frame.
[0010] The first guide frame is disposed at the end of the frame, and the number of guide hooks on the first guide frame is greater than or equal to the sum of the number of guide hooks on the third guide frame and the fourth guide frame, and the number of guide hooks on the second guide frame is greater than or equal to the number of guide hooks on the fourth guide frame.
[0011] Furthermore, the frame includes a first frame fixedly connected to the front of the frame and a second frame slidably connected between the first frame and the frame along the Y direction. A plurality of winding plates are fixedly connected to the side of the second frame adjacent to the first frame. The winding plates are provided with circular holes that pass through along the Y direction. Each circular hole is connected to an annular steel collar. A plurality of winding drive assemblies are provided on the frame. One end of each of the winding drive assemblies extends along the Y direction to the inner ring of the steel collar and is limited and connected to the winding drum, thereby driving the winding drum to rotate. A single filament positioning assembly is connected to the first frame. One end of the single filament positioning assembly is connected to the first frame, and the other end extends along the Z direction to the front of the winding drum and corresponds to the center of the winding drum.
[0012] Furthermore, the inner diameter of the steel collar is larger than the diameter of the end face of the winding spool, and the inner circle of the steel collar is connected to a steel collar hook.
[0013] Furthermore, the second frame is connected to the output end of the displacement drive component, and the other end of the displacement drive component is fixedly connected to the frame. Under the driving action of the displacement drive component, the second frame drives the steel collar to reciprocate along the Y direction outside the take-up drum.
[0014] Furthermore, the winding drums are arranged in an N×M matrix, and the number of the winding drive assembly, the winding drums, the monofilament positioning assembly, and the steel collar corresponds one-to-one.
[0015] Furthermore, the number of third guide frames is several. Along the X-axis from the first row of guide frames to the second row of guide frames, the extension length of the several third guide frames along the Y-axis decreases in a gradient manner, and the extension length of each third guide frame is less than the extension length of the second row of guide frames.
[0016] Furthermore, the number of fourth guide frames is several. Along the X-axis from the first row of guide frames to the second row of guide frames, the extension length of several fourth guide frames along the Y-axis gradually decreases, and the extension length of the fourth guide frame adjacent to the second row of guide frames is less than the extension length of the second row of guide frames.
[0017] Furthermore, each of the third guide frames and each of the fourth guide frames is provided with a guide hook at a position at the far end relative to the frame, and the number of guide hooks at the far end of the third guide frame and the fourth guide frame is the same as the number of take-up spools in the same column.
[0018] Furthermore, the guide hooks at the distal ends of the third guide frame and the fourth guide frame are arranged in an alternating pattern.
[0019] Furthermore, the single filament positioning assembly includes a wire bearing, a positioning bracket, a positioning base, and a limiting component. One end of the positioning bracket is hinged to the positioning base through the limiting component and is limited to the outside of the positioning base. The inside of the positioning base is fixedly connected to the first frame.
[0020] The top of the positioning bracket has a bending angle, and the cable bearing is vertically connected to the top of the positioning bracket, so that its axis has a downward tilt angle relative to the XY plane.
[0021] The intelligent wire drawing, twisting, and winding machine provided in the embodiments of this application has at least the following beneficial effects:
[0022] This application utilizes a guide unit extending along the Y direction at the top of the machine frame, consisting of a first row of guide frames, a second row of guide frames, a third row of guide frames, and a fourth row of guide frames. Each guide frame has a specific guide hook with a defined function. The first row of guide frames, located at the end of the machine frame, has the most guide hooks and initiates the initial introduction and diversion of all the threads. The third and second rows of guide frames further guide the threads in batches, and the threads on the second row of guide frames are precisely guided to the single-filament positioning component via the fourth guide frame. This layered and graded thread guiding method achieves orderly batch guidance of the threads. By precisely controlling the number of guide hooks and the thread direction of each guide frame, each thread has an independent and clear path, avoiding disorderly crossing between threads and fundamentally eliminating thread entanglement. This significantly improves the stability and continuity of production, effectively overcoming the shortcomings of traditional thread guiding layouts, and offering advantages such as reasonable thread routing, high reliability, and strong practicality. Attached Figure Description
[0023] Figure 1a , Figure 1b These are schematic diagrams of the overall structure of an intelligent wire drawing, twisting and winding machine according to this application from different perspectives;
[0024] Figure 2a , Figure 2b These are enlarged views of different parts of the guide unit;
[0025] Figure 3 This is a schematic diagram of the winding drive assembly fixed to the frame in this application;
[0026] Figure 4 This is a partially enlarged schematic diagram of the winding drive assembly in this application;
[0027] Figure 5 This is a schematic diagram of the monofilament positioning component in this application.
[0028] Numbers in the diagram
[0029] 1-Retracting spool; 2-Guiding unit; 20-Guide hook; 21-First row of guide frames; 22-Second row of guide frames; 23-Third guide frame; 24-Fourth guide frame; 3-Displacement drive assembly; 4-Retracting transmission assembly; 42-Long shaft; 43-Sleeve; 46-Pulley; 5-Steel collar; 6-Wire winding plate; 7-Single wire positioning assembly; 71-Wire guide bearing; 72-Positioning bracket; 73-Positioning base; 74-Limiting assembly; 75-Rotating shaft; 8-Belt; 9-Motor; S-Frame; S0-Frame; S1-First frame; S2-Second frame. Detailed Implementation
[0030] The present application will now be further described based on preferred embodiments and with reference to the accompanying drawings.
[0031] Furthermore, for ease of understanding, various components on the drawings have been enlarged or reduced, but this is not intended to limit the scope of protection of this application.
[0032] Singular forms of words also include plural meanings, and vice versa.
[0033] In the description of the embodiments of this application, it should be noted that if terms such as "upper," "lower," "inner," or "outer" are used to indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this application is in use, they are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. In addition, in the description of this application, in order to distinguish different units, the terms "first," "second," etc. are used in this specification, but these are not limited by the manufacturing order, nor should they be construed as indicating or implying relative importance. Their names may differ in the detailed description and claims of this application.
[0034] The vocabulary used in this specification is for illustrative purposes and is not intended to limit the scope of this application. It should also be noted that, unless otherwise expressly specified and limited, the terms "set," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, a direct connection, or an indirect connection via an intermediate medium; or they can refer to the internal communication between two components. Those skilled in the art will understand the specific meaning of these terms in this application.
[0035] For ease of description, with reference to Figure 1, the axial direction of the take-up drum 1 is defined as the Y-axis direction, the extension direction of the first frame S1 is defined as the X-axis direction, and the axial direction of the monofilament positioning component 7 located directly in front of the take-up drum 1 is defined as the Z-axis direction. The three axes are perpendicular to each other.
[0036] like Figure 1a , Figure 1bAs shown, an intelligent wire drawing, twisting, and winding machine includes a first frame S1 fixedly connected to the front of a frame S0, and a second frame S2 slidably connected between the first frame S1 and the frame S0 along the Y direction, together forming the frame S. A guide unit 2 extending along the Y direction is provided on the top of the frame S. Several winding plates 6 are fixedly connected to the side of the second frame S2 adjacent to the first frame S1. Each winding plate 6 has a through-hole along the Y direction, and an annular steel collar 5 is connected to each hole. The frame S0 has several... A winding drive assembly 4, one end of each winding drive assembly 4 extends along the Y direction to pass through the inner ring of the steel collar 5 and is limited and connected to the winding drum 1, and drives the winding drum 1 to rotate, together forming a winding drive assembly. A single filament positioning assembly 7 is connected to the first frame S1. One end of the single filament positioning assembly 7 is connected to the first frame S1, and the other end extends along the Z direction to the front of the winding drum 1 and corresponds to the center of the winding drum 1, and is used to guide the direction of the filament in front of the winding drum 1.
[0037] In some preferred embodiments, such as Figure 2a , Figure 2b As shown, the guiding unit 2 includes a first row of guide frames 21, a second row of guide frames 22, and a third row of guide frames 23 and a fourth row of guide frames 24 respectively arranged at intervals on both sides of the second row of guide frames 22. Each guide frame is provided with a guide hook 20. Several guide hooks 20 located on the first row of guide frames 21 and the second row of guide frames 22 are arranged sequentially along the length of their respective guide frames. The first row of guide frames 21 is located at the end of the frame S, and the number of guide hooks 20 on the first row of guide frames 21 is greater than or equal to the number of guide hooks 20 on the third row of guide frames 23 and the fourth row of guide frames 24. The number of guide hooks 20 on the guide frame 22 is greater than or equal to the number of guide hooks 20 on the fourth guide frame 24. All the threads are introduced through the guide hooks 20 on the first guide frame 21. Some of the threads are introduced through the guide hooks 20 on the third guide frame 23 to the corresponding single filament positioning component 7 below them. The remaining threads are introduced through the guide hooks 20 on the second guide frame 22. The threads on the guide hooks 20 on the second guide frame 22 are introduced through the guide hooks 20 on the fourth guide frame 24 to the corresponding single filament positioning component 7 below them, so as to achieve orderly guidance of the threads in batches.
[0038] In some preferred embodiments, the winding drums 1 of the winding machine are arranged in an N×M matrix. For example, the number of steel collars 5 is 36. The winding transmission components 4 are arranged in a rectangular matrix of 3 rows and 12 columns. The number of winding transmission components 4, winding drums 1, and single filament positioning components 7 corresponds one-to-one with the number of steel collars 5.
[0039] In some preferred embodiments, the number of third guide frames 23 is several. Along the X-axis, in the layout order from the first row of guide frames 21 to the second row of guide frames 22, the extension length of several third guide frames 23 along the Y-axis gradually decreases, and the extension length of each third guide frame 23 is less than the extension length of the second row of guide frames 22, so as to avoid excessive length interfering with the threads guided to the second row of guide frames 22.
[0040] In some preferred embodiments, the number of fourth guide frames 24 is several. Along the X-axis from the first row of guide frames 21 to the second row of guide frames 22, the extension length of the several fourth guide frames 24 along the Y-axis gradually decreases, and the extension length of the fourth guide frame 24 adjacent to the second row of guide frames 22 is less than the extension length of the second row of guide frames 22. This ensures that the second row of guide frames 22 plays a leading role in the thread guiding and distribution process. At the same time, the fourth guide frames 24 can accurately cooperate to smoothly guide the thread to the corresponding monofilament positioning component 7, thereby improving the accuracy and stability of thread guiding.
[0041] In some preferred embodiments, each of the third guide frame 23 and each of the fourth guide frame 24 is provided with a guide hook 20 at the far end relative to the frame S, which is used to meet the matrix arrangement requirements of the winding drum 1 while realizing orderly cable routing.
[0042] In some preferred embodiments, the number of guide hooks 20 located at the far ends of the third guide frame 23 and the fourth guide frame 24 is the same as the number of take-up spools 1 located in the same column, so as to establish a precise one-to-one guiding relationship between the guide hooks 20 and the take-up spools 1 in the same column.
[0043] In some preferred embodiments, the guide hooks 20 at the distal ends of the third guide frame 23 and the fourth guide frame 24 are arranged in an alternating manner to ensure that each filament can be accurately and independently guided to the corresponding monofilament positioning component 7, while effectively avoiding tangling and interference between the filaments.
[0044] In some preferred embodiments, such as Figure 3As shown, the winding transmission assembly 4 includes a long shaft 42 and a sleeve 43 coaxially and limitedly connected to the outside of the long shaft 42. The sleeve 43 is fixedly connected to the frame S. Both ends of the long shaft 42 extend out of the two end faces of the sleeve 43, and one end is connected to a pulley 46. The pulley 46 is connected to a motor 8 via a belt 9. Each winding transmission assembly 4 is equipped with a motor 8. Under the driving action of the motor 8, the belt 9 drives the long shaft 42 to rotate.
[0045] Furthermore, the other end of the long shaft 42 is connected to the take-up spool 1, and the sleeve 43 forms a support span between the two ends of the long shaft 42. Bearings are respectively limited at both ends of the sleeve 43. The inner and outer rings of the two bearings cooperate with and limit the long shaft 42 and the sleeve 43 respectively. The two ends of the long shaft 42 rotate coaxially under the radial support of the two bearings, which is used to make the long shaft 42 more stable during the rotation and winding process, and effectively reduce the amplitude of the jump at the load-bearing end where the take-up spool 1 is located when it drives the take-up spool 1 to rotate.
[0046] In some preferred embodiments, such as Figure 4 As shown, the inner diameter of the steel collar 5 is larger than the diameter of the end face of the take-up drum 1, and the inner circle of the steel collar 5 is connected to a steel collar hook 25. The second frame S2 is connected to the output end of the displacement drive component 3, and the other end of the displacement drive component 3 is fixedly connected to the frame S0. Under the driving action of the displacement drive component 3, the second frame S2 drives the steel collar 5 to move back and forth along the Y direction outside the take-up drum 1, so that the wire can be guided by the steel collar hook 25 and evenly wound around the surface of the take-up drum 1 along its axial direction.
[0047] In some preferred embodiments, the displacement drive assembly 3 is provided in at least two sets, and the two sets of displacement drive assemblies 3 are respectively provided on both sides of the back of the second frame S2. Preferably, the displacement drive assembly 3 is a straight cylinder, which has the advantages of fast response, simple structure and easy maintenance.
[0048] In some preferred embodiments, such as Figure 5 As shown, the monofilament positioning assembly 7 includes a wire bearing 71, a positioning bracket 72, a positioning base 73, and a limiting assembly 74. The inner side of the positioning base 73 is fixedly connected to the frame S. One end of the positioning bracket 72 is hinged to the positioning base 73 through the limiting assembly 74 and is limited to the outer side of the positioning base 73. One end of the limiting assembly 74 passes through the positioning bracket 72 and abuts against the positioning base 73 under the action of elastic force, so that the positioning bracket 72 can rotate flexibly around the limiting assembly 74 to adjust its position. At the same time, the elastic abutment ensures that it is stably limited during operation and avoids loosening due to vibration or other factors.
[0049] In some preferred embodiments, the top of the positioning bracket 72 has a bending angle, and the thread bearing 71 is vertically connected to the top of the positioning bracket 72 via a rotating shaft 75. The axis of the thread bearing 71 has a downward tilt angle relative to the XY plane, which is used to guide the thread from above and downwards. This effectively avoids the problem that the thread is easily dislodged from the groove due to inertia and gravity when the winding drum stops because the thread bearing 71 is horizontally arranged, and the thread needs to be repositioned every time it is rewound.
[0050] In some preferred embodiments, along the circumferential direction of the wiring bearing 71, the radial dimension of the middle part of the wiring bearing 71 is smaller than the radial dimensions of its two ends, so as to form a wiring groove on the outer surface of the wiring bearing 71. This allows the wire to be confined to the outer surface of the wiring bearing 71 through the wiring groove for wiring, and during the wiring process, the wiring bearing 71 can also be driven to rotate around its axis, reducing frictional resistance and reducing the wear of the wire during the wiring process.
[0051] The specific embodiments of this application have been described in detail above. For those skilled in the art, several improvements and modifications can be made to this application without departing from the principle of this application, and these improvements and modifications also fall within the protection scope of the claims of this application.
Claims
1. An intelligent wire drawing, twisting, and winding machine, comprising a winding spool (1), a winding transmission assembly (4), a steel collar (5), and a monofilament positioning assembly (7) integrated on a frame (S), characterized in that: It also includes a guide unit (2) that is located on top of the frame (S) and extends along the Y direction; The guide unit (2) includes a first row of guide frames (21), a second row of guide frames (22), a third row of guide frames (23), and a fourth row of guide frames (24). The third row of guide frames (23) and the fourth row of guide frames (24) are arranged at intervals and respectively located on both sides of the second row of guide frames (22). Each guide frame is provided with a guide hook (20). Several guide hooks (20) located on the first row of guide frames (21) and the second row of guide frames (22) are arranged sequentially along the length direction of the guide frame. The first guide frame (21) is disposed at the end of the frame (S), and the number of guide hooks (20) on the first guide frame (21) is greater than or equal to the sum of the number of guide hooks (20) on the third guide frame (23) and the fourth guide frame (24), and the number of guide hooks (20) on the second guide frame (22) is greater than or equal to the number of guide hooks (20) on the fourth guide frame (24).
2. The intelligent wire drawing, twisting, and winding machine according to claim 1, characterized in that: The frame (S) includes a first frame (S1) fixedly connected to the front of the frame (S0), and a second frame (S2) slidably connected between the first frame (S1) and the frame (S0) along the Y direction. A plurality of winding plates (6) are fixedly connected to the side of the second frame (S2) adjacent to the first frame (S1). Each winding plate (6) has a through-hole along the Y direction, and each hole is connected to an annular steel collar (5). The frame (S0) has a plurality of take-up conveyors. The moving component (4) has one end of each of the winding drive components (4) extending along the Y direction to the inner ring opening of the steel collar (5) and being limited and connected to the winding drum (1), thereby driving the winding drum (1) to rotate. A single filament positioning component (7) is connected on the first frame (S1). One end of the single filament positioning component (7) is connected to the first frame (S1), and the other end extends along the Z direction to the front of the winding drum (1) and corresponds to the center of the winding drum (1).
3. The intelligent wire drawing, twisting, and winding machine according to claim 2, characterized in that: The inner diameter of the steel collar (5) is larger than the diameter of the end face of the winding drum (1), and the inner circle of the steel collar (5) is connected to a steel collar hook (25).
4. The intelligent wire drawing, twisting, and winding machine according to claim 3, characterized in that: The second frame (S2) is connected to the output end of the displacement drive assembly (3), and the other end of the displacement drive assembly (3) is fixedly connected to the frame (S0). Under the driving action of the displacement drive assembly (3), the second frame (S2) drives the steel collar (5) to move back and forth along the Y direction outside the winding drum (1).
5. The intelligent wire drawing, twisting, and winding machine according to claim 1, characterized in that: The winding drum (1) is arranged in an N×M matrix, and the number of winding drive assembly (4), winding drum (1), single wire positioning assembly (7), and steel collar (5) are in one-to-one correspondence.
6. The intelligent wire drawing, twisting, and winding machine according to claim 4, characterized in that: The number of the third guide frames (23) is several. Along the X-axis from the first arranged guide frames (21) to the second arranged guide frames (22), the extension length of the several third guide frames (23) along the Y-axis decreases in a gradient, and the extension length of each third guide frame (23) is less than the extension length of the second arranged guide frames (22).
7. The intelligent wire drawing, twisting, and winding machine according to claim 4, characterized in that: The number of fourth guide frames (24) is several. Along the X-axis from the first arranged guide frame (21) to the second arranged guide frame (22), the extension length of several fourth guide frames (24) along the Y-axis gradually decreases, and the extension length of the fourth guide frame (24) adjacent to the second arranged guide frame (22) is less than the extension length of the second arranged guide frame (22).
8. The intelligent wire drawing, twisting, and winding machine according to claim 5 or 6, characterized in that: Each of the third guide frame (23) and each of the fourth guide frames (24) is provided with a guide hook (20) at a position at the far end relative to the frame (S), and the number of guide hooks (20) at the far end of the third guide frame (23) and the fourth guide frame (24) is the same as the number of take-up spools (1) in their respective columns.
9. The intelligent wire drawing, twisting, and winding machine according to claim 7, characterized in that: The guide hooks (20) at the far ends of the third guide frame (23) and the fourth guide frame (24) are arranged in an alternating pattern.
10. The intelligent wire drawing, twisting, and winding machine according to claim 7, characterized in that: The single-wire positioning assembly (7) includes a wire bearing (71), a positioning bracket (72), a positioning base (73), and a limiting assembly (74). One end of the positioning bracket (72) is hinged to the positioning base (73) through the limiting assembly (74) and is limited to the outside of the positioning base (73). The inside of the positioning base (73) is fixedly connected to the first frame (S1). The top of the positioning bracket (72) has a bending angle, and the wiring bearing (71) is vertically connected to the top of the positioning bracket (72), so that its axis has a downward tilt angle relative to the XY plane.