Thread rolling machine with a cooling system

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention

[0001] This invention relates to a thread-rolling machine and relates particularly to a thread-rolling machine having a cooling system.2. Description of the Related Art

[0002] Referring to Fig. 1, a conventional thread rolling machine 1 includes a base unit 11, a feeding track 12 disposed on the base unit 11 and adapted to feed screw blanks 2, a thread-rolling unit 13 disposed on the base unit 11 and adapted to form threads on the screw blanks 2, and a transmission device 14 linked with the thread-rolling unit 13. Specifically, the base unit 11 includes a base 111 on which the thread-rolling unit 13 is installed and a transmission box 112 located on one side of the base 111 and linked with the transmission device 14. Furthermore, the thread-rolling unit 13 includes a movable rolling die 132 slidably disposed on the base 111 and a stationary rolling die 131 disposed on the base 111 and opposite the movable rolling die 132. When the thread rolling machine 1 is actuated, screw blanks 2 are sequentially fed from the feeding track 12 into the thread-rolling unit 13. The sliding motion of the movable rolling die 132 is driven by the operation of the transmission device 14, which causes the screw blanks 2 to be pressed by rolling between the movable rolling die 132 and the stationary rolling die 131. Thus, the rolling process forms threads on each screw blank 2 to produce each screw product 5.

[0003] However, regarding the use of the thread rolling machine 13, each screw blanks 2 is subjected to strong squeezing and rolling forces between the movable rolling die 132 and the stationary rolling die 131, which generates heat because of mutual friction. Meanwhile, the movable rolling die 132 slides incessantly under the high-speed transmission of the transmission device 14, which causes heat on the base unit 11. The heat expansion of the base unit 11 occurs by the heat, which not only affects the precision of the thread rolling operation of the movable rolling die 132 but also causes the concern over the poor quality of the screw product 5. In addition, the overheated base unit 11 incurs the abrasion problem, with the result that the service life of the thread rolling machine 1 is affected. Thus, the improvement is required.

[0004] Relevant machines known to the person skilled in the art are disclosed by prior arts, such as TW 1644743 B, which forms the basis for the preamble of claim 1, CN 204620965 U, CN 212239056 U, CN 217701168 U, and CN 205147190 U.SUMMARY OF THE INVENTION

[0005] An object of this invention is to provide a thread-rolling machine with a cooling system capable of reducing the temperature of the base during a thread rolling operation, thereby increasing the thread rolling quality and prolonging the service life of the thread rolling machine.

[0006] A thread-rolling machine with a cooling system of this invention is as defined in claim 1 and includes a base, a feeding track disposed on the base, a thread-rolling unit disposed on the base, and a transmission assemblage linked with the thread-rolling unit. The base includes a transmission portion and a working portion. The transmission assemblage is installed on the transmission portion, and the thread-rolling unit is disposed on the working portion and driven by the transmission assemblage. The thread-rolling unit includes a movable rolling die and a stationary rolling die opposite the movable rolling die. The working portion includes a body unit and a shield unit disposed on the body unit. The movable rolling die is slidably disposed on the body unit and covered by the shield unit. The thread-rolling machine further includes a cooling system connected to the base. The cooling system includes a cooler, at least one working channel formed in the working portion, a pipe unit connected to the cooler and the working channel, and a working fluid flowing through the cooler, the working channel and the pipe unit. The cooler includes a cooler body, at least one inlet formed through the cooler body, and at least one outlet formed through the cooler body. The working fluid is sent to the cooler body when the working fluid passes through the inlet, and the working fluid is sent out when the working fluid passes through the outlet. The pipe unit is connected to the working channel, the inlet, and the outlet, thereby communicating the pipe unit with the working portion and the cooler and allowing the working fluid to flow through and circulate between the working channel and cooler body. The working fluid is cooled by the cooler body, and the cooled working fluid is sent to the working channel for executing a heat exchanging process, thereby attaining a cooling circulation capable of reducing the temperature of the working portion.

[0007] Preferably, in one preferred embodiment, the working channel is formed in the body unit. In another preferred embodiment, the working channel is formed in the shield unit. In a further preferred embodiment, more than one working channel can be formed. For instance, a working channel is formed in the body unit, and another working channel is formed in the shield unit. Accordingly, the pipe unit is connected to each of the working channels and also connected to the inlet and the outlet of the cooler body. It is possible that the pipe unit is disposed between the working channel of the shield unit and the working channel of the body unit so that the cooled working fluid can pass through the outlet, flow between the shield unit and the body unit, and thence return back to the cooler body by flowing through the inlet.

[0008] Preferably, a first collecting tank is disposed under the base and adapted to store cutting fluid, and a second collecting tank is disposed under the base and adapted to store lubricating oil. In one preferred embodiment, the pipe unit is connected to the inlet of the cooler body and the first collecting tank so that the cutting fluid can be sent from the first collecting tank into the cooler body, which allows the cutting fluid to be defined as the working fluid for attaining a cooling effect. Alternatively, in another preferred embodiment, the pipe unit is connected to the inlet of the cooler body and the second collecting tank so that the lubricating oil can be sent from the second collecting tank into the cooler body, which allows the lubricating oil to be defined as the working fluid for attaining a cooling effect.

[0009] Preferably, in one preferred embodiment, when the lubricating oil is defined as the working fluid, it is possible that the transmission portion includes a transmission box on which the transmission assemblage is disposed, and a heat-dissipating channel is formed in the transmission box. The pipe unit is connected to the working channel and the heat-dissipating channel, which allows the lubricating oil to flow through the cooler body of the cooler, the working channel, and the heat-dissipating channel and then return back to the second collecting tank.BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Fig. 1is a perspective view showing a conventional thread-rolling machine; Fig. 2is a perspective view showing a first preferred embodiment of this invention; Fig. 3is an enlarged view of Fig. 2; Fig. 4is a schematic view showing one variant of the first preferred embodiment; Fig. 5is a schematic view showing another variant of the first preferred embodiment wherein one flowing route of the working fluid is shown; Fig. 6is a schematic view showing a further variant of the first preferred embodiment wherein another flowing route of the working fluid is shown; Fig. 7is a schematic view showing a second preferred embodiment of this invention; Fig. 8is a schematic view showing one variant of the second preferred embodiment; Fig. 9is a schematic view showing another variant of the second preferred embodiment; Fig. 10is a schematic view showing a third preferred embodiment of this invention; Fig. 11is a schematic view showing one variant of the third preferred embodiment; Fig. 12is a schematic view showing another variant of the third preferred embodiment; Fig. 13is a schematic view showing a fourth preferred embodiment of this invention; Fig. 14is a schematic view showing one variant of the fourth preferred embodiment; and Fig. 15is a schematic view showing another variant of the fourth preferred embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Referring to Fig. 2 and Fig. 3, a first preferred embodiment of this invention is related to a thread-rolling machine 3. The thread-rolling machine 3 includes a base 31, a feeding track 32 disposed on the base 31 and supplying screw blanks 4, a thread-rolling unit 33 disposed on the base 31 for forming threads on the screw blanks 4, a transmission assemblage 34 linked with the thread-rolling unit 33, and a cooling system 35 connected to the base 31. Specifically, the base 31 is mainly divided into two portions. In other words, the base 31 includes a transmission portion 312 and a working portion 311. The transmission assemblage 34 is installed on the transmission portion 312, and the thread-rolling unit 33 is disposed on the working portion 311 and driven by the transmission assemblage 34. Specifically, the working portion 311 includes a body unit 3111 and a shield unit 3112 disposed on the body unit 3111. The thread-rolling unit 33 includes a movable rolling die 331 slidably installed on the body unit 3111 and a stationary rolling die 332 disposed on the base 31 and opposite the movable rolling die 331. The movable rolling die 331 is actuated by the transmission assemblage 34 to execute a reciprocating sliding motion with respect to the stationary rolling die 332 for forming threads on the screw blanks 4, thereby producing screw products 5. The shield unit 3112 can be disposed on a top surface of the body unit 3111, and the thread-rolling unit 33 can be partially covered by the shield unit 3112, thereby protecting the thread-rolling unit 33 with the shield unit 3112.

[0012] The cooling system 35 includes a cooler 351, at least one working channel 352 formed in the working portion 311, a pipe unit 353 connected to the cooler 351 and the working channel 352, and a working fluid flowing through the cooler 351, the working channel 352, and the pipe unit 353. The cooler 351 includes a cooler body 3510, at least one inlet 3511 formed through the cooler body 3510, and at least one outlet 3512 formed through the cooler body 3510. Take for example the cooler body 3510 has one inlet 3511 and one outlet 3512 formed thereon in the preferred embodiments. Furthermore, the working fluid is a cooling substance which flows and is not solid, and herein the working fluid is briefly shown by arrows illustrated in Fig. 5, Fig. 6, etc. The working fluid can be stored in the cooler 351 or be introduced into the cooler 351 by an external device. When the working fluid is sent to the cooler body 3510 by passing through the inlet 3511, the cooler body 3510 serves to cool down the working fluid, i.e. reduce the temperature of the working fluid. The working fluid is sent out by passing through the outlet 3512. The pipe unit 353 can be comprised of a plurality of pipes. Owing to these pipes, the pipe unit 353 is connected to the working channel 352, the inlet 3511, and the outlet 3512, thereby communicating the pipe unit 353 with an interior of the working portion 311 and an interior of the cooler 351 and allowing the working fluid to flow through and circulate between the working channel 352 and cooler body 3510. After the working fluid is cooled by the cooler body 3510 of the cooler 351, the cooled working fluid is sent to the working channel 352, and a heat exchanging process is conducted in the working channel 352 by the flow of the working fluid.

[0013] In the preferred embodiments, one or more than one working channel 352 can be adopted according to demand. For example, Fig. 2 shows that the working channel 352 is formed in the body unit 3111. Fig. 4 shows that the working channel 352 is formed in the shield unit 3112. Alternatively, a working channel 352 is formed in the body unit 3111, and another working channel 352 is formed in the shield unit 3112, as shown in Fig. 5. When the working channels 352 are respectively formed in the body unit 3111 and in the shield unit 3112, the pipe unit 353 is connected to each working channel 352 and also connected to the inlet 3511 and the outlet 3512 of the cooler body 3510. Particularly, the pipe unit 353 can be further disposed between the working channel 352 of the shield unit 3112 and the working channel 352 of the body unit 3111 so that the working fluid can flow through the outlet 3512, flow between the shield unit 3112 and the body unit 3111, and thence return back to the cooler body 3510 by flowing through the inlet 3511.

[0014] As for example shown in Figs. 3-5, the working channel 352 can include at least one first port 3521 which allows the working fluid to flow in and at least one second port 3522 which allows the working fluid to flow out. Herein, two scenarios are shown as examples. The first scenario shown in Fig. 5 is that the pipe unit 353 is connected to the outlet 3512 and the first port 3521 of the shield unit 3112. Then, the pipe unit 353 is connected to the second port 3522 of the shield unit 3112 and the first port 3521 of the body unit 3111. Finally, the pipe unit 353 is connected to the second port 3522 of the body unit 3111 and the inlet 3511. Accordingly, as traveled by arrows in Fig. 5, the flowing route of the working fluid can be, sequentially, from the cooler 351, the shield unit 3112, the body unit 3111, and thence back to the cooler 351. The second scenario shown in Fig. 6 is that the pipe unit 353 is connected to the outlet 3512 and the first port 3521 of the body unit 3111. Then, the pipe unit 353 is connected to the second port 3522 of the body unit 3111 and the first port 3521 of the shield unit 3112. Finally, the pipe unit 353 is connected to the second port 3522 of the shield unit 3112 and the inlet 3511. Accordingly, as traveled by arrows in Fig. 6, the flowing route of the working fluid can be, sequentially, from the cooler 351, the body unit 3111, the shield unit 3112, and thence back to the cooler 351.

[0015] The operation of this invention is described with the aid of Fig. 2 and Fig. 3. When the thread rolling machine 3 starts a thread rolling operation, screw blanks 4 are sequentially fed by the feeding track 32 and introduced into the thread-rolling unit 33. Owing to the transmission of the transmission assemblage 34, the movable rolling die 331 moves in a reciprocating motion with respect to the stationary rolling die 332, which allows each screw blank 4 to be pressed and rolled between the movable rolling die 331 and the stationary rolling die 332. Accordingly, threads are formed on each screw blank 4 to produce each screw product 5. During the thread rolling operation, there is heat caused by the quick movement of the movable rolling die 332, and the heat is transferred to the body unit 3111 and the shield unit 3112 and incurs high temperature, which causes the working portion 311 to get hot. Because the cooling system 35 includes the cooler 351 adapted to reduce the temperature of the working fluid and also includes the working channel 352 formed in the body unit 3111, the working fluid cooled by the cooler body 3510 of the cooler 351 is sent to the working channel 352 by means of the pipe unit 353. When the cooled working fluid enters the working channel 352, a heat exchange process caused by the flowing action of the working fluid is conducted in the working channel 352 to reduce the temperature of the body unit 3111 efficiently, thereby attaining a cooling effect. The temperature of the shield unit 3112 which is in contact with the body unit 3111 can also be reduced. Accordingly, the use of the cooling system 35 attains a preferable cooling effect to prevent the working portion 311 from getting too hot and prevent the occurrence of the heat expansion, which facilitates an increase in the precision of the thread rolling operation and prolongs the service life of the thread rolling machine 3.

[0016] Referring to Fig. 7, a second preferred embodiment of this invention is shown. The correlated elements of the first preferred embodiment are applied to the second preferred embodiment and herein are not repeated. The second preferred embodiment is characterized in that a first collecting tank 313 is disposed under the base 31 and adapted to store cutting fluid, and a second collecting tank 314 is disposed under the base 31 and adapted to store lubricating oil. In the second preferred embodiment, the pipe unit 353 is connected to the inlet 3511 of the cooler 351 and the second connecting tank 314, so the lubricating oil is sent from the second collecting tank 314 into the cooler body 3510. In this case, this feature can be combined with the arrangement, the working channel 352 of which is only formed in the body unit 3111 or is only formed in the shield unit 3112, and the combinations are respectively shown in Fig. 7 and Fig. 8. This feature can also be combined with the arrangement, the working channels 352 of which are respectively formed in the body unit 3111 and the shield unit 3112, and the combination is shown in Fig. 9.

[0017] In the second preferred embodiment, the lubricating oil can be defined as the working fluid for reducing the temperature, thereby attaining a cooling effect. Accordingly, the working fluid, i.e. the lubricating oil, flows through the cooler body 3510 and then enters the working channel 352. After the heat exchange process, the lubricating oil passes through the second port 3522 so that the lubricating oil can be discharged from the working channel 352 into the second collecting tank 314, as for example shown by arrows in Fig. 7. The lubricating oil inside the second collecting tank 314 can be sent to the cooler 351 repetitively to attain a circulating effect, thereby reducing the temperature of the body unit 3111 and the shield unit 3112.

[0018] Referring to Fig. 10, a third preferred embodiment of this invention is shown. The correlated elements of the second preferred embodiment are applied to the third preferred embodiment and herein are not repeated. The third preferred embodiment is characterized in that the transmission portion 312 includes a transmission box 36 on which the transmission assemblage 34 is disposed. A heat-dissipating channel 36a is formed in the transmission box 36. The pipe unit 353 is not only connected to the second collecting tank 314 and the cooler body 3510 but also connected to the working channel 352 and the heat-dissipating channel 36a. Preferably, the pipe unit 353 is extended from the second port 3522 of the working channel 352 to the heat-dissipating channel 36a, thereby allowing the lubricating oil to flow through the cooler 351, the working channel 352, and the heat-dissipating channel 36a of the transmission box 36 and then return back to the second collecting tank 314. In this case, this feature can be respectively combined with the arrangement, the working channel 352 of which is only formed in the body unit 3111 or is only formed in the shield unit 3112, and the combinations are respectively shown in Fig. 10 and Fig. 11. This feature can also be combined with the arrangement, the working channels 352 of which are respectively formed in the body unit 3111 and the shield unit 3112, and the combination is shown in Fig. 12.

[0019] In the third preferred embodiment, the lubricating oil flows through the cooler 351, so the temperature of the lubricating oil is reduced to prevent the lubricating oil from decaying because of high temperature. When the lubricating oil flows through the working channel 352 and the heat-dissipating channel 36a, the temperatures of the shield unit 3112, the body unit 3111, the transmission box 36, and the transmission portion 312 can be reduced. The temperature of the thread-rolling unit 33 disposed on the body unit 3111 can also be reduced. Thus, a decrease in the temperature of the whole thread-rolling machine 3 is attained while conducting the thread rolling operation, which facilitates a long-term use of the thread-rolling machine 3.

[0020] According to the second preferred embodiment and the third preferred embodiment, the lubricating oil serves as the working fluid whereby the temperatures of the working portion 311 and the transmission portion 312 can be efficiently reduced for attaining a cooling effect. The lubricating oil can be directly discharged from the working channel 352 into the second collecting tank 314 (as for example shown by arrows in Fig. 7) or be discharged from the working channel 352, then the transmission box 36, and thence into the second collecting tank 314 (as for example shown by arrows in Fig. 10), thereby attaining the circulation of the lubricating oil and preventing the lubricating oil from mixing with other substances, such as cutting fluid. Thus, the lubricating oil and cutting fluid can be respectively collected, and the decay of the lubricating oil caused by the mixing behavior is also prevented.

[0021] Referring to Fig. 13, a fourth preferred embodiment of this invention is shown. The correlated elements of the first preferred embodiment are applied to the fourth preferred embodiment and herein are not repeated. The fourth preferred embodiment is characterized in that a first collecting tank 313 is disposed under the base 31 and adapted to store cutting fluid, and a second collecting tank 314 is disposed under the base 31 and adapted to store lubricating oil. In the fourth preferred embodiment, the pipe unit 353 is connected to the inlet 3511 and the first connecting tank 313, so the cutting fluid is sent from the first collecting tank 313 into the cooler body 3510. In this case, this feature can be combined with the arrangement, the working channel 352 of which is only formed in the body unit 3111 or is only formed in the shield unit 3112, and the combinations are respectively shown in Fig. 13 and Fig. 14. This feature can also be combined with the arrangement, the working channels 352 of which are respectively formed in the body unit 3111 and the shield unit 3112, and the combination is shown in Fig. 15.

[0022] In the fourth preferred embodiment, the cutting fluid flows through the cooler 351, so the temperature of the cutting fluid is reduced. When the cutting fluid flows through the working channel 352, the temperatures of the shield unit 3112, the body unit 3111, and the thread-rolling unit 33 can be reduced. Thus, a decrease in the temperature of the whole thread-rolling machine 3 is attained while conducting the thread rolling operation, which facilitates a long-term use of the thread-rolling machine 3.

[0023] According to the fourth preferred embodiment, the cutting fluid serves as the working fluid whereby the temperatures of the working portion 311 can be efficiently reduced for attaining a cooling effect. As for example shown by arrows in Fig. 13, the cutting fluid can be directly sent from the working channel 352 to the first collecting tank 313 for attaining the circulation of the cutting fluid and preventing the cutting fluid from mixing with other substances, such as lubricating oil. Thus, the lubricating oil and cutting fluid can be respectively collected, and the decay of the lubricating oil caused by the mixing behavior is also prevented.

[0024] To sum up, the thread rolling machine of this invention is characterized in that the cooling system includes a working channel formed in the working portion of the base and also includes a cooler communicating with the working channel by means of a pipe unit and serving to cool a working fluid. The cooled working fluid is sent to the working channel and subjected to a heat exchanging process in the working channel, thereby reducing the temperatures of the working portion and the thread-rolling unit, which prevents the occurrence of the heat expansion efficiently, increases the precision of the thread rolling operation, and prolongs the service life of the whole thread-rolling machine.

[0025] While the embodiments are shown and described above, it is understood that further variations and modifications may be made without departing from the scope of this invention as defined in the appended claims.

Claims

1. A thread-rolling machine (3) with a cooling system (35) comprising a base (31), a feeding track (32) disposed on said base (31) and supplying screw blanks (4), a thread-rolling unit (33) disposed on said base (31) for forming threads on said screw blanks (4), and a transmission assemblage (34) linked with said thread-rolling unit (33), wherein said base (31) includes a transmission portion (312) and a working portion (311), with said transmission assemblage (34) installed on said transmission portion (312), and said thread-rolling unit (33) disposed on said working portion (311) and driven by said transmission assemblage (34), said thread-rolling unit (33) including a movable rolling die (331) and a stationary rolling die (332) opposite said movable rolling die (331); characterized in that said working portion (311) includes a body unit (3111) and a shield unit (3112) disposed on said body unit (3111), said movable rolling die (331) being slidably disposed on said body unit (3111) and covered by said shield unit (3112), a cooling system (35) being connected to said base (31), said cooling system (35) including a cooler (351), at least one working channel (352) formed in said working portion (311), a pipe unit (353) connected to said cooler (351) and said working channel (352), and a working fluid flowing through said cooler (351), said at least one working channel (352) and said pipe unit (353), said cooler (351) including a cooler body (3510), at least one inlet (3511) formed through said cooler body (3510), and at least one outlet (3512) formed through said cooler body (3510), said working fluid being sent to said cooler body (3510) when said working fluid passes through said inlet (3511), said working fluid being sent out when said working fluid passes through said outlet (3512), said pipe unit (353) being connected to said at least one working channel (352), said at least one inlet (3511), and said at least one outlet (3512), thereby communicating saidpipe unit (353) with said working portion (311) and said cooler (351) and allowing said working fluid to flow through and circulate between said working channel (352) and cooler body (3510), said working fluid being cooled by said cooler (351), said cooled working fluid being sent to said working channel (352), and said cooled working fluid which flows in said working channel (352) being subjected to a heat exchanging process whereby a cooling circulation is attained to reduce the temperature of said working portion (311).

2. The thread-rolling machine (3) according to claim 1, wherein said at least one working channel (352) includes at least one first port (3521) connected to said pipe unit (353) for allowing said working fluid to flow in and at least one second port (3522) connected to said pipe unit (353) for allowing said working fluid to flow out.

3. The thread-rolling machine (3) according to claim 1, wherein said at least one working channel (352) is formed in said body unit (3111).

4. The thread-rolling machine (3) according to claim 1, wherein said at least one working channel (352) is formed in said shield unit (3112).

5. The thread-rolling machine (3) according to claim 1, wherein said cooling system (35) includes more than one working channel (352), with a working channel (352) formed in said body unit (3111), and another working channel (352) formed in said shield unit (3112), said pipe unit (353) being connected to each said working channel (352) and also connected to said at least one inlet (3511) and said at least one outlet (3512) of said cooler body (3510).

6. The thread-rolling machine (3) according to claim 4, wherein said pipe unit (353) is disposed between said working channel (352) of said shield unit (3112) and said working channel (352) of said body unit (3111) so that said cooled working fluid can flow through said outlet (3512), flow between said shield unit (3112) and said body unit (3111), and thence return back to said cooler body (3510) by flowing through said inlet (3511).

7. The thread-rolling machine (3) according to any one of claims 1 to 5, further comprising a first collecting tank (313) disposed under said base (31) and adapted to store cutting fluid, said pipe unit (353) being connected to said at least one inlet (3511) of said cooler body (3510) and said first collecting tank (313) so that said cutting fluid can be sent from said first collecting tank (313) into said cooler body (3510), said cutting fluid being defined as said working fluid for reducing the temperature of said working portion (311), thereby attaining a cooling effect.

8. The thread-rolling machine (3) according to any one of claims 1 to 5, further comprising a second collecting tank (314) disposed under said base (31) and adapted to store lubricating oil, said pipe unit (353) being connected to said at least one inlet (3511) of said cooler body (3510) and said second collecting tank (314) so that said lubricating oil can be sent from said second collecting tank (314) into said cooler body (3510), said lubricating oil being defined as said working fluid for reducing the temperature of said working portion (311), thereby attaining a cooling effect.

9. The thread-rolling machine (3) according to claim 8, wherein said transmission portion (312) includes a transmission box (36) on which said transmission assemblage (34) is disposed, a heat-dissipating channel (36a) being formed in said transmission box (36), said pipe unit (353) being connected to said at least one working channel (352) and said heat-dissipating channel (36a), thereby allowing said lubricating oil to flow through said cooler body (3510) of said cooler (351), said at least one working channel (352), and said heat-dissipating channel (36a) and then return back to said second collecting tank (314).