WO2007133039A1

WO2007133039A1 - Apparatus for manufacturing spring

Info

Publication number: WO2007133039A1
Application number: PCT/KR2007/002376
Authority: WO
Inventors: Jung-Hyung Lee
Original assignee: Diabell Co., Ltd.
Priority date: 2006-05-15
Filing date: 2007-05-15
Publication date: 2007-11-22
Also published as: KR100688380B1

Abstract

Disclosed is an apparatus for manufacturing springs using a wire as a spring material in which the spring material is curved to form curved portions. The spring manufacturing apparatus comprises a rotating member adapted to be alternately rotated in left and right directions and a pair of coiling bars mounted to the rotating member and arranged parallel to each other at a certain interval. According to the spring manufacturing apparatus, the spring material is curved by the rotation of the coiling bars mounted to the rotating member to form curved portions, thereby considerably reducing the occurrence of cracks and scratches in the spring material. The spring manufacturing apparatus can be linked with an automated manufacturing system to manufacture high-quality springs on an industrial scale at reduced costs and shorten the manufacturing procedure of the springs.

Description

APPARATUS FOR MANUFACTURING SPRING

Technical Field

[1] The present invention relates to an apparatus for manufacturing springs, and more specifically to an apparatus for manufacturing springs in which a spring material is curved by the rotation of coiling bars mounted to a rotating member to form curved portions, thereby considerably reducing the occurrence of cracks and scratches in the spring material.

[2]

Background Art

[3] In general, springs are defined as members having elasticity. Springs are adapted for use as parts of large-scale equipment, including construction machinery, automobiles, airplanes, etc. Springs are also used in small-sized products, such as scales and home appliances. In recent years, springs have been used in opening/closing units of folder type mobile phones and operating units of slide mobile phones. That is, the demand for springs will increase to an unlimited extent.

[4] Springs are classified into coil springs, conical springs, leaf springs, torsion springs, spiral springs, washer springs, disc springs, clip springs, etc. by their applications and shapes. The coil springs are manufactured by winding rod- shaped metallic materials ( e.g., round steel bars and square steel bars) in a cylindrical and spiral shape. The coil springs can be used even under tension and compression. Compression coil springs may be used in a laminate form. The torsion springs are springs that receive a torsional stress in a rotational direction relative to their axial line to acquire bending elastic energy. According to the installation methods of the torsion springs in a structure, the torsion springs are also symmetrically arranged in a double-barrel fashion at both sides of the structure. The torsion springs can be processed in various forms using the torsion force applied thereto and are advantageous in terms of space utilization. The coil springs are applied to various industrial machineries, such as automobiles, textile machines, agricultural machines, electrical and electronic components and building interior/exterior materials. The leaf springs may be individually used or, in most cases, they are jointly used. The leaf springs are processed in various forms despite their small volume. The leaf springs are divided according to whether they use spring functions or spring characteristics. A relatively thin leaf spring effectively utilizes a stress but is susceptible to damage during processing in the presence of scratches or cracks when compared to a relatively thick leaf spring. Laminated leaf springs having a trapezoidal or triangular cross section are used in the places where a large force is applied. The main applications of the leaf springs are automobiles, electrical and electronic toys, and various clip-type products, but are not limited thereto.

[5] Most general coil springs have been manufactured manually using non-precision instruments, such as shaft rods and tools for winding heat-treated coils, by skilled operators, resulting in decreased productivity and making it difficult to manufacture uniform final products.

[6] To find solutions to the problems associated with the manual operations, mechanical apparatuses and methods for manufacturing springs have been developed. An exemplary mechanical apparatus for manufacturing springs is shown in FIGs. 1, 2 and 3. The apparatus is used to curve a spring steel 200 to form curved portions, cut the curved spring steel into shorter steel pieces, and form hooks in the respective steel pieces. All processes are carried out within the mechanical apparatus to achieve high mass productivity.

[7] Specifically, the curved portions of the spring material 200 are formed by striking the spring material from the upper and lower directions or the left and right directions using striking members 100, 110 and 120. As shown in FIG. 1, during transfer of the spring material 200, the spring material 200 is struck (or pressurized) by the striking members 100 with a predetermined force from the upper and lower directions of the spring material 200 to form curved portions of the spring material. This operation is called 'coiling'.

[8] However, cracks are liable to occur in the final springs formed with curved portions. Particularly, in the case where the spring material has a very small thickness, cracks cause serious damage to the elasticity and resistance of the final springs, leading to low quality and increased manufacturing costs of the springs.

[9]

Disclosure of Invention Technical Problem

[10] Therefore, the present invention has been made in view of the above problems, and it is an object of the present invention to provide an apparatus for manufacturing springs in which a spring material is curved by the rotation of coiling bars mounted to a rotating member to form curved portions, thereby considerably reducing the occurrence of cracks and scratches in the spring material.

[11] The spring manufacturing apparatus of the present invention can be linked with an automated manufacturing system to manufacture high-quality springs on an industrial scale at reduced costs and shorten the manufacturing procedure of the springs.

[12]

Technical Solution [13] In accordance with an aspect of the present invention for achieving the above object, there is provided an apparatus for manufacturing springs using a wire as a spring material, the apparatus comprising a rotating member adapted to be alternately rotated in left and right directions and a pair of coiling bars mounted to the rotating member and arranged parallel to each other at a certain interval. The use of the coiling bars in the spring manufacturing apparatus of the present invention enables the manufacture of high-quality springs while avoiding the formation of scratches and defects at the ends of curved portions of the wire.

[14] The spring manufacturing apparatus of the present invention is characterized in that the rotational angle of the rotating member is controllable. The controllable rotational angle of the rotating member allows a user to freely modify the dimension of the curved portions of the final springs and broadens the choice of various spring manufacturing processes, so that the user can select an optimal spring manufacturing procedure.

[15] The spring manufacturing apparatus of the present invention further comprises a feeder for automatically supplying the wire between the pair of coiling bars. The automatic supply of the wire achieves automated manufacturing of springs. Also, the supply speed of the wire from the feeder is regulated to control the distance between the curved portions formed by the periodically alternating rotation of the rotating member and the pitch of the springs.

[16] The pair of coiling bars are provided separately from the rotating member to control the distance between the coiling bars. The distance between the coiling bars is varied to modify the dimension of the curved portions of the wire.

[17] The spring manufacturing apparatus of the present invention further comprises a guide member for preventing the wire having curved portions formed by the rotation of the coiling bars from being bent. The guide member serves to prevent the wire from being crooked and bent in a certain direction during formation of the curved portions.

[18] The guide member is provided with a leaf spring on its contact face with the wire to continuously supply the wire and prevent irregular bending of the wire while maintaining smooth curving operation of the coiling bars without any impediment to the curving operation.

[19] The spring manufacturing apparatus of the present invention further comprises a cutting unit for cutting the spring material having curved portions formed by the rotation of the coiling bars to a predetermined size. The use of the cutting unit in the spring manufacturing apparatus of the present invention eliminates the need to take an inconvenient step of cutting the wire after formation of the curved portions of the springs, thus contributing to the simplification of the spring manufacturing procedure.

[20] Brief Description of the Drawings

[21] The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which: [22] FIG. 1 illustrates a conventional method for curving a spring material to form curved portions; [23] FIGs. 2 and 3 illustrate conventional striking members for curving respective spring materials to form curved portions; [24] FIG. 4 is a perspective view of a spring manufacturing apparatus according to one embodiment of the present invention;

[25] FIG. 5 is a cross-sectional view taken along line 'A-A' of FIG. 4;

[26] FIG. 6 is a top view illustrating coiling bars of a spring manufacturing apparatus according to another embodiment of the present invention; [27] FIG. 7 is a perspective view of a spring manufacturing apparatus according to a preferred embodiment of the present invention; [28] FIG. 8 is a view illustrating an operational state of a spring manufacturing apparatus according to one embodiment of the present invention; and [29] FIG. 9 is a view illustrating an operational state of a spring manufacturing apparatus according to another embodiment of the present invention. [30]

Mode for the Invention [31] The constitutions and operations of the present invention will now be described in detail with reference to the accompanying drawings. [32] Referring to FIG. 4 illustrating one embodiment of the present invention, there is provided a spring manufacturing apparatus 1 comprising a rotating member 30, coiling bars 40, position adjusting portions 50 and a driving motor 70. [33] According to a basic structure of the spring manufacturing apparatus 1, the rotating member 30 is rotated to form curved portions of a spring material, the coiling bars 40 are mounted at the circumference of the rotating member, and the driving motor 70 serves to rotate the rotating member. [34] The shape of the rotating member 30 is not particularly limited so long as the rotating member 30 can be rotated. For example, the rotating member 30 may be a cylinder or may have a polygonal cross section. Preferably, the rotating member 30 is in the form of a rotating roller. The coiling bars 40 are mounted to the rotating roller.

Preferably, the position adjusting portions 50 are formed such that the distance between the coiling bars 40 can be adjusted. The spring manufacturing apparatus may further comprise a feeder (not shown) for supplying a wire as a spring material and a guide member (not shown) for stably curving the wire. These additional elements will be explained below with reference to FIGs. 8 and 9.

[35] The shape of the position adjusting portions 50 may vary depending on the shape and dimension of the coiling bars 40. Specifically, position moving grooves are preferably adapted to the dimension of the coiling bars 40 so that the coiling bars 40 can be moved upwardly and downwardly to control the dimension of the curved portions of the spring material and the size of the final springs. As shown in FIG. 4, the coiling bars are inserted into the respective position adjusting grooves formed at the circumference of the rotating member 30. Preferably, each of the position adjusting grooves is provided with a fixing means therein to fix the corresponding coiling bar.

[36] The rotating member 30 is preferably configured to control its rotational angle when being rotated. The rotating member 30 may be rotated at an angle of 360° and is preferably rotated at an angle of 0° to 180°. With this configuration, the rotating member can control the curvature of the curved portions to provide convenience in that the elasticity and rigidity of the final springs correspond to the needs of users.

[37] A moving means, such as a linear gear, may be attached to the rotating member 30 to move the rotating member 30 in a horizontal direction. This configuration of the rotating member 30 provides the advantage that a user can stop and reinitiate the spring manufacturing procedure at a desired stage according to the choice of the user.

[38] The coiling bars 40 mounted to the rotating member 30 may be a cylinder or may have a polygonal cross section. The coiling bars 40 may be fixedly mounted at the circumference of the rotating member 30. Preferably, the coiling bars 40 are configured such that they are movable upwardly and downwardly through the respective position adjusting grooves 50. This configuration of the coiling bars 40 enables the springs to have a dimension corresponding to the needs of users. As a result, an inter- changeability of manufacturing lines can be provided to manufacture various springs, thus contributing to an improvement in productivity and efficiency of the manufacturing processes.

[39] Taking into consideration the improvement of workability and the precision of coiling, the coiling bars 40 are preferably made of a rigid metallic material. Alternatively, the coiling bars 40 may be made of a non-metallic material, such as a plastic or solid material, having a strength not to damage the spring material during processing. As a result, more stable manufacturing processes can be guaranteed when the curved portions of the spring material are formed and precise coiling of the curved portions can be carried out. The coiling bars preferably have a cylindrical shape.

[40] The rotational speed (RPM) of the driving motor 70 for rotating the rotating member 30 is preferably controllable. The speed of the coiling operation is varied depending on the rotational speed of the driving motor 70. Particularly, the functions ( e.g., intermittent rotation and stopping) of the driving motor 70 can be manipulated to ensure an improvement in the efficiency of the coiling operation.

[41] Referring to FIGs. 5 and 6, arrangements of the coiling bars 40 and the position adjusting grooves 50 will be explained below.

[42] As shown in FIG. 5, position adjusting grooves are formed at the ends of the outer circumference of the rotating member 30. The coiling bars are arranged such that they are fixedly inserted into the respective position adjusting grooves. A fixing protrusion (41) formed within each of the position adjusting grooves is fixedly fitted into a fixing recess (51) formed in each of the coiling bars. The fixing protrusion is in the form of an elastic ball bearing. Each of the coiling bars is inserted into the corresponding position adjusting groove to couple the fixing protrusion to the fixing recess. Importantly, the position of the pair of coiling bars can be varied. As explained above, the coiling bars may be inserted into the outer circumference of the rotating member. Alternatively, a plurality of position adjusting grooves are arranged on the front face of the rotating member and the coiling bars are inserted into the front face of the rotating member.

[43] FIG. 6 illustrates another arrangement of the coiling bars 40 and the position adjusting grooves 50. In a general case, the formation of the position adjusting grooves is omitted and the pair of coiling bars are fixed to the front face of the rotating member. More preferably, the position adjusting grooves are formed on the front face of the rotating member 30 and the coiling bars 40 are protruded from the front face of the rotating member through the respective position adjusting grooves 50. Particularly, the position adjusting grooves 50 serve as guide rails allowing the coiling bars to move in left and right directions within the respective position adjusting grooves 50, and at the same time, a fixing protrusion formed within each of the position adjusting grooves is fixedly fitted into an elastic bearing formed in each of the coiling bars.

[44] The operation of the spring manufacturing apparatus according to the foregoing preferred embodiment of the present invention will be explained in more detail below with reference to FIG. 7.

[45] Referring to FIG. 7, the pair of coiling bars 40 are fixed to the rotating member 30.

More preferably, the pair of coiling bars 40 can be arranged such that the distance between the coiling bars is controlled. That is, the pair of coiling bars 40 are inserted into the rotating member 30 through the position adjusting portions 50 formed at the circumference of the rotating member 30. When it is required to control the dimension and size of the final springs, the distance between the coiling bars can be adjusted by moving the coiling bars along the respective position adjusting grooves. The adjustment of the distance between the coiling bars is as explained in FIGs. 5 and 6.

[46] The rotating member is rotated in left and right directions by means of the driving motor 70. The rotational angle of the rotating member can be controlled according to the intended dimension of the final springs. That is, the coiling of the spring material is initiated by the rotational movement of the coiling bars 40. Before the coiling, the distance between the coiling bars can be adjusted depending on the dimension of the springs to ensure ease of the operation and diversity of the processes. Furthermore, the use of the rotational movement of the coiling bars in left and right directions considerably reduces the number of cracks formed in the curved portions of the spring material, compared to a conventional operation for striking a spring material to form curved portions.

[47] Methods for manufacturing springs using the respective spring manufacturing apparatuses according to the embodiments of the present invention will be explained below with reference to FIGs. 8 and 9, but the present invention is not limited to these methods.

[48] Referring to FIG. 8, a feeder 60 is operated to introduce a wire 80 as a spring material into a space between the coiling bars 40. The feeder 60 may be composed of suitable units, such as transfer rollers. Particularly, the feeder is configured to regulate the supply speed of the wire. The distance between the curved portions of the final springs can be varied by increasing or reducing the supply speed of the wire by the feeder.

[49] It is ideal that the wire is accurately introduced into the central portion of the space between the coiling bars 40. Of course, there may be a slight deviation in the introduction of the wire into the central portion of the space. This slight deviation can be corrected by the adjustment of the position adjusting portions 50.

[50] Next, a suitable rotational angle is set in the rotating member 30. This setting is performed to control the curvature of the curved portions of the final springs and determines the degree of elasticity of the springs. Accordingly, the curvature of the curved portions must be controlled taking into consideration the convenience of a user, the type of the operation and the kind of the elastic body. The lead angle and the pitch of the springs can be varied depending on the rotational angle of the rotating member 30. It will be appreciated that the lead angle and pitch of the springs can be varied by regulating the supply speed of the wire by means of the feeder other than the rotational angle of the rotating member.

[51] Thereafter, the driving motor 70 begins to rotate at the set rotational angle and the spring material is introduced at the regulated speed. At this time, a sensor can be operated to detect the rotation of the driving motor and the introduction of the spring material and to initiate the driving of the rotating member 30. The rotation of the coiling bars 40 mounted to the rotating member 30 serves to curve the spring material to form curved portions, thereby considerably reducing the occurrence of cracks and scratches in the spring material.

[52] FIG. 9 illustrates a method for manufacturing springs using another spring manufacturing apparatus different from that shown in FIG. 8.

[53] The spring manufacturing apparatus shown in FIG. 9 is provided with a pair of coiling bars 40. As explained in FIG. 6, the distance between the coiling bars may be fixed or varied by the position adjusting grooves.

[54] First, a wire 80 as a spring material is supplied at a constant speed by means of a feeder (not shown). A rotating member 30 is rotated in left and right directions by a controlled rotational angle to form curved portions of the spring material, as shown in the figure. The lead angle and the pitch of final springs can be varied by regulating the supply speed of the wire by means of the feeder and adjusting the distance between the coiling bars.

[55] When the wire 80 is supplied by means of the feeder and the coiling bars are rotated to form curved portions of the wire, there is a risk that the wire 80 may be irregularly crooked or bent in a certain direction. To avoid the risk, the wire is pressurized by at least one guide member 90 to allow the curved springs to have the same degree of flatness.

[56] Here, a pair of guide members 90 may be used. It is preferred to provide an elastic pressurizing part at a contact site between the guide member and the wire. It is particularly preferable to provide a leaf spring 91 at the contact site. The pressurizing part allows the feeder to smoothly supply the wire without stopping the operation even when the wire is pressurized by the guide member.

[57] The guide member 90 may be applied to the spring manufacturing apparatuses according to the embodiments of the present invention and has the advantages that the degree of flatness of the final springs can be maintained constant and the stability of the manufacturing processes can be guaranteed.

[58] Further, each of the spring manufacturing apparatuses according to the embodiments of the present invention further comprises a cutting unit (not shown) capable of cutting the curved spring material to a predetermined dimension. The use of the cutting unit ensures the stability and efficiency of the continuous processes. Furthermore, in view of the efficiency of the continuous processes, each of the spring manufacturing apparatuses according to the present invention can be linked with a control part comprising sensors for detecting the states of the respective processes, i.e. loading of the spring material, control of the rotational speed, detection of the cutting time, etc., and delivering the states to users to control the overall processing. That is, the present invention can be constituted as an automated processing system. The automated processing system enables the manufacture of springs with more stable quality and shortens the processing time to achieve reduced manufacturing costs. After the formation operation of the curved portions is finished, the cutting unit is used to cut the curved spring material at the final stage to make the continuous processes more efficient.

[59] Although the present invention has been described herein with reference to the foregoing embodiments, it will be apparent to those skilled in the art that various modifications to the embodiments are possible without departing from the spirit or scope of the inventions.

[60] The technical spirit of the invention should be determined by the appended claims and their equivalents, rather than by the foregoing description.

[61]

Industrial Applicability

[62] As apparent from the above description, according to the spring manufacturing apparatus of the present invention, a spring material is curved by the rotation of coiling bars mounted to a rotating member to form curved portions, thereby considerably reducing the occurrence of cracks and scratches in the spring material.

[63] The spring manufacturing apparatus can be linked with an automated manufacturing system to manufacture high-quality springs on an industrial scale at reduced costs and shorten the manufacturing procedure of the springs.

Claims

[1] An apparatus for manufacturing springs using a wire as a spring material, the apparatus comprising: a rotating member adapted to be alternately rotated in left and right directions; and a pair of coiling bars mounted to the rotating member and arranged parallel to each other at a certain interval. [2] The apparatus according to claim 1, wherein the rotating member is configured to control its rotational angle. [3] The apparatus according to claim 1, further comprising a feeder for automatically supplying the wire between the pair of coiling bars. [4] The apparatus according to claim 1, wherein the pair of coiling bars are provided separately from the rotating member to control the distance between the coiling bars. [5] The apparatus according to claim 1, further comprising a guide member for preventing the wire having curved portions formed by the rotation of the coiling bars from being bent. [6] The apparatus according to claim 5, wherein the guide member is provided with a leaf spring on its contact face with the wire. [7] The apparatus according to claim 1, further comprising a cutting unit for cutting the spring material having curved portions formed by the rotation of the coiling bars to a predetermined size.