Test hydraulic oil cooling equipment

Abstract

The utility model relates to the technical field of hydraulic oil cooling equipment, and particularly discloses test hydraulic oil cooling equipment which comprises an equipment box body and further comprises a first quick connector, a second quick connector and a third quick connector, a fourth quick connector and a fifth quick connector are arranged at the top of the equipment box body, and the fifth quick connector is communicated with a Y-shaped communicating pipe. According to the test hydraulic oil cooling equipment, the temperature of circulating hydraulic oil is monitored through the arranged circulating cooling mechanism, and when the temperature of the hydraulic oil breaks through the normal working temperature range of the oil, the hydraulic oil is rapidly cooled through the circulating cooling mechanism, so that the temperature of the hydraulic oil is rapidly cooled, and the test efficiency is improved. The oil temperature is cooled to the normal temperature of 45 DEG C in a matched mode, system faults caused by out-of-control oil temperature are avoided, system pressure balance is maintained, oil liquid can directly return to an equipment oil source to be reused after being cooled and filtered, long-time natural cooling is not needed, and the test interval time is greatly shortened.

Description

TECHNICAL FIELD

[0001] The utility model relates to hydraulic oil cooling equipment technical field, concretely is a kind of test hydraulic oil cooling equipment. BACKGROUND

[0002] Servo mechanism closed system refers to the hydraulic transmission circuit of servo mechanism (high-precision control execution element, such as servo oil cylinder, servo motor) adopts "closed circulation" design system, and hydraulic oil mainly circulates in the closed loop formed by "hydraulic pump→servo control element→execution element", and does not directly return to oil tank (or oil tank only bears the auxiliary functions of oil supplementing, buffering and exhaust, instead of main oil return channel).

[0003] In order to test whether servo mechanism can meet the design requirements (such as control precision, response speed, stability, etc.), while checking the potential problems specific to closed system, the servo mechanism is tested under simulated actual working scene or extreme working condition, but the core feature of servo mechanism closed system is oil closed circulation and less heat exchange with the outside world, which causes the oil to continuously circulate in the system during testing, resulting in continuous rise of oil temperature, breaking the normal working temperature range of oil, and if relying on natural cooling, high-temperature oil needs to be placed for a long time to drop to normal temperature, which causes the servo mechanism test to be unable to continuously proceed, therefore, we propose a kind of test hydraulic oil cooling equipment. UTILITY MODEL CONTENTS

[0004] The utility model aims at providing a kind of test hydraulic oil cooling equipment to solve the problem that oil continuously circulates in the system during testing, resulting in continuous rise of oil temperature, breaking the normal working temperature range of oil, and if relying on natural cooling, high-temperature oil needs to be placed for a long time to drop to normal temperature, which causes the servo mechanism test to be unable to continuously proceed.

[0005] To achieve the above purpose, the utility model provides the following technical scheme: a kind of test hydraulic oil cooling equipment, comprising equipment box body, the bottom of equipment box body is equipped with multiple brake castors;It further includes quick connector one, quick connector two and quick connector three, quick connector one, quick connector two and quick connector three are located below the back of equipment box body, and quick connector four and quick connector five are arranged on the top of equipment box body;High-pressure filling pipe is communicated between quick connector one and quick connector four, and oil inlet high-pressure ball valve is installed on the end of high-pressure filling pipe close to quick connector four, and high-pressure filling pipe is fixed with the inner wall of equipment box body;Y-shaped communication pipe is communicated with quick connector five, and two branch pipes of Y-shaped communication pipe are respectively equipped with oil return low-pressure ball valve one and oil return low-pressure ball valve two, low-pressure oil pipe is communicated with quick connector two, and two-way filter is communicated with the branch pipe of Y-shaped communication pipe on the end of low-pressure oil pipe far from quick connector two;

[0006] A circulating cooling mechanism is installed between the quick connector three and the branch pipe of the Y-type connecting pipe. The circulating cooling mechanism detects the temperature of the circulating hydraulic oil and circulates and cools the high-temperature hydraulic oil.

[0007] The circulating cooling mechanism includes an oil tank, which is fixed inside the equipment housing. The oil tank is connected to a branch pipe of a Y-shaped connecting pipe. A circulating pump set is installed on the inner wall of the equipment housing. A hose 1 is connected to the outer side of the oil tank and is connected to the circulating pump set. A hose 2 is connected to the circulating pump set. A valve set is installed at the end of hose 2 away from the circulating pump set. A hose 3 is connected to the outer side of the valve set. An air cooler is fixedly connected to the inner wall of the equipment housing. Hose 3 passes through the air cooler and is connected to the oil tank. A hose 4 is connected to the outer side of the oil tank and passes through the air cooler and is connected to the valve set. A hose 5 is connected to the outer side of the valve set. A return oil filter is connected at the end of hose 5 away from the valve set. A hose 6 is connected between the return oil filter and quick connector 3.

[0008] The valve assembly includes a valve block, which is connected to hoses two, three, four and five respectively. A normally open solenoid valve, a normally closed solenoid valve and a safety valve are installed on the outside of the valve block.

[0009] An air filter is installed on the top of the fuel tank.

[0010] The oil tank is equipped with a temperature sensor, and the equipment housing is equipped with an oil temperature display instrument, which is connected to the temperature sensor.

[0011] The equipment housing is equipped with a counter display instrument, a circulating pressure gauge, a main power button, a circulating cooling start / stop button, an oil tank drain start / stop button, an oil tank low level alarm button, and an oil tank high level alarm button.

[0012] The equipment housing is equipped with an alarm indicator light and a buzzer alarm. The low-pressure return oil ball valve one and the low-pressure return oil ball valve two are each equipped with a limit switch, which is connected to the alarm indicator light and the buzzer alarm respectively.

[0013] The equipment housing has ventilation holes on its surface.

[0014] A liquid level relay is fixedly installed on the top of the oil tank, and the low liquid level alarm button and the high liquid level alarm button are respectively connected to the liquid level relay.

[0015] Among them, quick connector one, quick connector two and quick connector three are vertically and equidistantly distributed on the lower back of the equipment box.

[0016] This utility model has at least the following beneficial effects:

[0017] In use, this application monitors the temperature of the circulating hydraulic oil through a set-in circulating cooling mechanism. When the hydraulic oil temperature exceeds the normal operating temperature range, the circulating cooling mechanism quickly dissipates heat from the hydraulic oil to cool it down to 45°C, thus preventing system failures caused by uncontrolled oil temperature and maintaining system pressure balance. After cooling and filtration, the oil can be directly returned to the equipment oil source for reuse without the need for long-term natural cooling, significantly shortening the test interval. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall design of this utility model;

[0019] Figure 2 This is a rear view schematic diagram of the present invention;

[0020] Figure 3 This is a schematic diagram of the internal structure of this utility model;

[0021] Figure 4 This is a schematic diagram of the circulating cooling mechanism of this utility model;

[0022] Figure 5 This is a schematic diagram of the valve assembly structure of this utility model;

[0023] Figure 6 This is a hydraulic schematic diagram of the present invention.

[0024] In the diagram: 1. Circulating pump set; 2. Normally open solenoid valve; 3. Air cooler; 4. Equipment housing; 5. Circulating pressure gauge; 6. Normally closed solenoid valve; 7. Return oil filter; 8. Temperature sensor; 9. Temperature display instrument; 10. Two-way filter; 11. Inlet high-pressure ball valve; 12. Return low-pressure ball valve one; 13. Return low-pressure ball valve two; 14. Oil tank; 15. Liquid level relay; 16. Air filter; 17. Quick connector one; 18. Quick connector two; 19. Quick connector four; 20. Quick connector five; 21. Quick connector three; 22. High-pressure filling pipe; 23. 24. Y-type connecting pipe; 25. Low-pressure oil pipe; 26. Circulating cooling mechanism; 27. Hope 1; 28. Hope 2; 29. ​​Valve assembly; 30. Hope 3; 31. Hope 5; 32. Hope 6; 33. Valve block; 34. Safety valve; 35. Counter display instrument; 36. Main power button; 37. Circulating cooling start / stop button; 38. Oil tank drain start / stop button; 39. Low liquid level alarm button; 40. Heat dissipation vent; 41. Brake caster; 42. Alarm indicator light; 43. Buzzer alarm; 44. Limit switch; 45. Oil tank high liquid level alarm button. Detailed Implementation

[0025] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0026] Please see Figures 1 to 6 This utility model provides a technical solution: a test hydraulic oil cooling device, including a device housing 4, with heat dissipation vents 40 on the surface of the housing 4 to ensure heat dissipation efficiency, and multiple brake casters 41 installed at the bottom of the housing 4; it also includes quick connectors 17, 18, and 21, which are located at the lower back of the housing 4 and are vertically equidistantly distributed at the lower back of the housing 4; quick connectors 17, 18, and 21 are located at the lower back of the housing 4; quick connectors 49 and 50 are provided at the top of the housing 4; a high-pressure filling pipe 22 connects quick connectors 17 and 419. A high-pressure filling pipe 22 is fitted with an inlet high-pressure ball valve 11 at one end near quick connector 4 19, and the high-pressure filling pipe 22 is fixed to the inner wall of the equipment box 4; quick connector 5 20 is connected to a Y-type connecting pipe 23, and two branches of the Y-type connecting pipe 23 are respectively fitted with a return low-pressure ball valve 12 and a return low-pressure ball valve 23; quick connector 2 18 is connected to a low-pressure oil pipe 24, and the end of the low-pressure oil pipe 24 away from quick connector 2 18 is connected to a bidirectional filter 10, and the bidirectional filter 10 is connected to a branch of the Y-type connecting pipe 23; a circulating cooling mechanism 25 is provided between quick connector 3 21 and the branch of the Y-type connecting pipe 23, and the circulating cooling mechanism 25 monitors the temperature of the circulating hydraulic oil and circulates and cools the high-temperature hydraulic oil.

[0027] Four brake casters 41 are installed at the bottom of the equipment housing 4. The casters are made of wear-resistant rubber and have a load-bearing capacity that matches the overall weight of the equipment. This allows the equipment to be fixed in place, making it easier to move and place in the testing environment and improving the flexibility of the equipment.

[0028] When using this application, quick connector 17, quick connector 28 and quick connector 321 are connected to the P (high pressure oil port), T (oil return port) and L (cooling oil return port) of the equipment oil source, respectively. Then quick connector 419 and quick connector 520 are connected to the high pressure oil port and low pressure oil port of the servo mechanism, respectively. After connection, check the locking state of the connectors to ensure reliable sealing and no leakage.

[0029] The servo mechanism's refueling process is divided into three channels:

[0030] The first route is for high-pressure refueling:

[0031] The operator connects quick connector 17 to the equipment oil source P port and quick connector 4 19 to the servo mechanism high-pressure oil port, ensuring a secure and sealed connection. Then, the operator opens the inlet high-pressure ball valve 11, allowing the high-pressure hydraulic oil supplied by the equipment oil source to enter the high-pressure filling pipe 22 via quick connector 17 and be injected into the servo mechanism load through the inlet high-pressure ball valve 11 and quick connector 4 19.

[0032] The return oil in the servo mechanism flows into the Y-type connecting pipe 23 through quick connector 5 20, enters the bidirectional filter 10 through the return oil low-pressure ball valve 12, and returns to the equipment oil source T port through quick connector 2 18 after filtration, completing the high-pressure filling cycle.

[0033] The second route is for low-pressure refueling:

[0034] Quick connector 218 connects to the T port of the equipment oil source, and quick connector 520 connects to the low-pressure oil port of the servo mechanism. The hydraulic oil supplied by the equipment oil source enters the low-pressure oil pipe 24 through quick connector 218, flows through the bidirectional filter 10 for filtration (to remove impurities), and then flows into the low-pressure oil port of the servo mechanism through the Y-type connecting pipe 23, the return oil low-pressure ball valve 12, and quick connector 520.

[0035] The low-pressure return oil of the servo mechanism flows in the reverse direction along the original path, and after being filtered again by the bidirectional filter 10, it returns to the equipment oil source through quick connector 2 18, completing the low-pressure filling cycle.

[0036] The third route is a circulating cooling system:

[0037] Open the low-pressure return ball valve 213. The return oil in the servo mechanism flows into the Y-type connecting pipe 23 through the quick connector 520. It then enters the circulating cooling mechanism 25 through the low-pressure return ball valve 213. The circulating cooling mechanism 25 monitors the temperature of the circulating hydraulic oil. When the hydraulic oil temperature exceeds the normal operating temperature range, the circulating cooling mechanism 25 quickly dissipates heat to cool the oil to 45°C, thus preventing system failures caused by uncontrolled oil temperature and maintaining system pressure balance. After cooling and filtration, the oil can be directly returned to the equipment oil source for reuse without long-term natural cooling, significantly shortening the test interval.

[0038] The circulating cooling mechanism 25 includes an oil tank 14, which is fixed inside the equipment housing 4. The oil tank 14 is connected to a branch pipe of the Y-shaped connecting pipe 23. A liquid level relay 15 is fixedly installed on the top of the oil tank 14. A circulating pump assembly 1 is installed on the inner wall of the equipment housing 4. A first hose 26 is connected to the outside of the oil tank 14 and is connected to the circulating pump assembly 1. A second hose 27 is connected to the circulating pump assembly 1. A valve assembly 28 is provided at the end of the second hose 27 away from the circulating pump assembly 1. A third hose 29 is connected to the outside of the valve assembly 28. The equipment housing 4... An air cooler 3 is fixedly connected to the inner wall. The air cooler 3 adopts a finned forced air cooling structure and is equipped with a high-power cooling fan. The forced convection heat exchange efficiency is high. The hose 329 passes through the air cooler 3 and is connected to the oil tank 14. The outside of the oil tank 14 is connected to the hose 430. The hose 430 passes through the air cooler 3 and is connected to the valve group 28. The outside of the valve group 28 is connected to the hose 531. The end of the hose 531 away from the valve group 28 is connected to the return oil filter 7. The return oil filter 7 and the quick connector 321 are connected to the hose 632.

[0039] Valve assembly 28 includes valve block 33, which is connected to hose 27, hose 39, hose 4, and hose 5 respectively. A normally open solenoid valve 2, a normally closed solenoid valve 6, and a safety valve 34 are installed on the outside of valve block 33.

[0040] The air filter 16 is installed on the top of the oil tank 14 and is made of high-efficiency filter cotton. While ensuring the balance of air pressure inside and outside the oil tank 14, it can block dust and moisture in the air from entering the oil tank 14, prevent oil contamination and emulsification, and extend the service life of the oil.

[0041] A temperature sensor 8 is installed on the top of the oil tank 14, and an oil temperature display instrument 9 is installed on the top of the equipment housing 4. The oil temperature display instrument 9 is connected to the temperature sensor 8.

[0042] The top of the equipment housing 4 is equipped with a counter display instrument 35, a circulating pressure gauge 5, a main power button 36, a circulating cooling start / stop button 37, an oil tank drain start / stop button 38, an oil tank low level alarm button 39, and an oil tank high level alarm button 45. The oil tank low level alarm button 39 and the oil tank high level alarm button 45 are respectively connected to the level relay 15.

[0043] A liquid level relay 15 is fixedly installed on the top of the oil tank 14, which, together with the low liquid level alarm button 39 and the high liquid level alarm button 45, enables full-range liquid level monitoring. When the liquid level is lower than the set lower limit, the low liquid level alarm is activated, and the circulating pump group 1 is automatically locked and cannot be started to avoid dry burning and damage to the pump group; when the liquid level is higher than the set upper limit, the high liquid level alarm is triggered to remind the operator to activate the oil draining function to prevent oil overflow from causing safety hazards and waste.

[0044] The top of the equipment housing 4 is equipped with an alarm indicator light 42 and a buzzer alarm 43. The low-pressure return oil ball valve 12 and the low-pressure return oil ball valve 2 13 are respectively equipped with limit switches 44, which are connected to the alarm indicator light 42 and the buzzer alarm 43 respectively.

[0045] Oil temperature display instrument 9 – This temperature display shows the oil temperature in the circulating oil tank 14, in °C.

[0046] Counter display instrument 35 — This displays the time, which is the time to monitor the oil discharge time, in seconds or minutes.

[0047] Circulation pressure gauge 5 – This pressure display shows the oil pressure discharged by circulation pump group 1, in bar.

[0048] Main power button 36 – When this button is pressed, the indicator light turns green, the device is powered on, and when the button is reset, the device is powered off.

[0049] Circulation Cooling Start / Stop Button 37 – When this button is pressed, the indicator light turns green, circulation pump group 1 starts, air cooler 3 starts, and cooling fan motor works. When the button is reset, circulation pump group 1 stops and cooling fan motor stops.

[0050] Oil tank drain start / stop button 38 - When this button is pressed, the indicator light turns green, the circulation pump group 1 starts, and the normally open solenoid valve 2 and normally closed solenoid valve 6 are energized; when the button is reset, the circulation pump group 1 starts, and the normally open solenoid valve 2 and normally closed solenoid valve 6 are de-energized.

[0051] Low oil level alarm button 39 - Low oil level alarm inside oil tank 14. When this alarm is activated, the circulating pump group 1 will not be able to start.

[0052] High oil level alarm button 45 - High oil level alarm inside oil tank 14. When this alarm is activated, the oil draining function of oil tank 14 should be turned on.

[0053] Alarm indicator light 42 is connected to return low-pressure ball valve 12 and return low-pressure ball valve 23, and is equipped with limit switch 44. When return low-pressure ball valve 12 and return low-pressure ball valve 23 are opened at the same time, alarm indicator light 42 on the top of the box turns green. When return low-pressure ball valve 12 and return low-pressure ball valve 23 are not opened at the same time, alarm indicator light 42 on the top of the box turns red. When return low-pressure ball valve 12 and return low-pressure ball valve 23 are closed at the same time, there is no color.

[0054] Buzzer alarm 43 is connected to return low-pressure ball valve 12 and return low-pressure ball valve 23. When the states of return low-pressure ball valve 12 and return low-pressure ball valve 213 are inconsistent, buzzer alarm 43 will sound; when the states of return low-pressure ball valve 12 and return low-pressure ball valve 213 are consistent, buzzer alarm 43 will not sound.

[0055] Safety valve 34 is set with a safety pressure threshold. When the system pressure exceeds the limit, it will automatically release pressure to avoid damage to components.

[0056] The circulating cooling and filtration process is as follows:

[0057] When the servo mechanism test causes the hydraulic oil temperature to rise (the maximum input oil temperature is 200℃), the oil tank 14 drain start / stop button 38 is opened, the indicator light turns green, the circulating pump group 1 starts, the normally open solenoid valve 2 is energized, and the oil tank 14 drain function is activated.

[0058] Open the low-pressure return ball valve 13, and high-temperature oil enters the oil tank 14;

[0059] Pressing the circulation cooling start / stop button 37 starts the circulation pump group 1 and the air cooler 3. The high-temperature oil in the oil tank 14 is drawn into the circulation pump group 1 through hose 1 26, pressurized, and enters the valve group 28 through hose 27. The solenoid valve 2 is opened frequently, and the oil flows into the air cooler 3. The oil is cooled by forced air cooling in the air cooler 3. The cooled oil flows back to the oil tank 14 through hose 3 29, forming a circulation cooling loop. The temperature sensor 8 detects the oil temperature in the oil tank 14 in real time and transmits the signal to the oil temperature display instrument 9, allowing the operator to view the temperature data intuitively. When the oil temperature cools to 45℃, the temperature sensor 8 sends a signal, the normally open solenoid valve 2 closes, and the normally closed solenoid valve 6 is energized. The oil at room temperature flows through the hose 30 through the air cooler 3 (secondary insulation), and after being filtered through the valve group 28, hose 31, and return oil filter 7, it returns to the equipment oil source through the quick connector 21, completing the cooling and filtration cycle. During the cycle, if the oil level in the tank 14 is lower than the set value, the low level alarm is activated, and the circulation pump group 1 cannot start; if the oil level is too high, the high level alarm is triggered, and the oil tank 14 needs to be opened to release pressure.

[0060] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0061] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A test hydraulic oil cooling apparatus comprising: The equipment box is provided with a plurality of brake casters at the bottom; The equipment box is provided with a quick connector one, a quick connector two and a quick connector three, which are located below the back of the equipment box, and the top of the equipment box is provided with a quick connector four and a quick connector five; The quick connector one is communicated with the high-pressure filling pipe, one end of the high-pressure filling pipe close to the quick connector four is provided with an oil inlet high-pressure ball valve, and the high-pressure filling pipe is fixed to the inner wall of the equipment box; The quick connector five is communicated with a Y-shaped communication pipe, two branches of the Y-shaped communication pipe are respectively provided with an oil return low-pressure ball valve one and an oil return low-pressure ball valve two, the quick connector two is communicated with a low-pressure oil pipe, one end of the low-pressure oil pipe away from the quick connector two is communicated with a bidirectional filter, and the bidirectional filter is communicated with the branch of the Y-shaped communication pipe; The quick connector three and the branch of the Y-shaped communication pipe are provided with a circulating cooling mechanism, which detects the temperature of circulating hydraulic oil and circulates and cools the high-temperature hydraulic oil.

2. The test hydraulic oil cooling device according to claim 1, characterized by: The circulating cooling mechanism comprises an oil tank, the oil tank is fixed in the equipment box, the oil tank is communicated with the branch of the Y-shaped communication pipe, a circulating pump group is installed on the inner wall of the equipment box, a soft pipe one is communicated with the outside of the oil tank, the soft pipe one is communicated with the circulating pump group, the circulating pump group is communicated with a soft pipe two, a valve group is arranged at one end of the soft pipe two away from the circulating pump group, a soft pipe three is communicated with the outside of the valve group, an air cooler is fixedly connected to the inner wall of the equipment box, the soft pipe three passes through the air cooler and is communicated with the oil tank, a soft pipe four is communicated with the outside of the oil tank, the soft pipe four passes through the air cooler and is connected with the valve group, a soft pipe five is connected to the outside of the valve group, an oil return filter is communicated with one end of the soft pipe five away from the valve group, and a soft pipe six is communicated between the oil return filter and the quick connector three.

3. The test hydraulic oil cooling device according to claim 2, characterized in that: The valve group comprises a valve block, the valve block is respectively communicated with the soft pipe two, the soft pipe three, the soft pipe four and the soft pipe five, and the valve block is provided with a normally open electromagnetic valve, a normally closed electromagnetic valve and a safety valve on the outside.

4. The test hydraulic oil cooling device according to claim 2, characterized by: An air filter is installed on the top of the oil tank.

5. The test hydraulic oil cooling device according to claim 2, characterized by: A temperature sensor is installed on the top of the oil tank, an oil temperature display instrument is installed on the top of the equipment box, and the oil temperature display instrument is connected with the temperature sensor.

6. The test hydraulic oil cooling device according to claim 2, characterized by: A counter display instrument, a circulating pressure gauge, a total power button, a circulating cooling start / stop button, an oil tank oil discharge start / stop button, an oil tank low liquid level alarm button and an oil tank high liquid level alarm button are installed on the top of the equipment box.

7. The test hydraulic oil cooling device according to claim 2, characterized by: An alarm indicator and a buzzer alarm are installed on the top of the equipment box, limit switches are respectively installed on the oil return low-pressure ball valve one and the oil return low-pressure ball valve two, and the limit switches are respectively connected with the alarm indicator and the buzzer alarm.

8. The test hydraulic oil cooling apparatus according to claim 1, characterized by: A heat dissipation opening is formed on the surface of the equipment box.

9. The test hydraulic oil cooling device according to claim 6, characterized by: A liquid level relay is fixedly installed on the top of the oil tank, and the oil tank low liquid level alarm button and the oil tank high liquid level alarm button are respectively connected with the liquid level relay.

10. The test hydraulic oil cooling apparatus according to claim 1, characterized by: The quick connector one, the quick connector two and the quick connector three are vertically and equidistantly distributed below the back of the equipment box.

Images